Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.InteractiveTreeSimplifier.sln
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.InteractiveTreeSimplifier.sln	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.InteractiveTreeSimplifier.sln	(revision 11010)
@@ -0,0 +1,34 @@
+﻿
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio 2013
+VisualStudioVersion = 12.0.30501.0
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4", "HeuristicLab.Problems.DataAnalysis.Symbolic.Views\3.4\HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4.csproj", "{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Debug|x64 = Debug|x64
+		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
+		Release|x64 = Release|x64
+		Release|x86 = Release|x86
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Debug|x64.ActiveCfg = Debug|x64
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Debug|x64.Build.0 = Debug|x64
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Debug|x86.ActiveCfg = Debug|x86
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Debug|x86.Build.0 = Debug|x86
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Release|x64.ActiveCfg = Release|x64
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Release|x64.Build.0 = Release|x64
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Release|x86.ActiveCfg = Release|x86
+		{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}.Release|x86.Build.0 = Release|x86
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+EndGlobal
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Exporters/SymbolicSolutionExcelExporter.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Exporters/SymbolicSolutionExcelExporter.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Exporters/SymbolicSolutionExcelExporter.cs	(revision 11010)
@@ -0,0 +1,359 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+using OfficeOpenXml;
+using OfficeOpenXml.Drawing.Chart;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  public class SymbolicSolutionExcelExporter : IDataAnalysisSolutionExporter {
+    private const string TRAININGSTART = "TrainingStart";
+    private const string TRAININGEND = "TrainingEnd";
+    private const string TESTSTART = "TestStart";
+    private const string TESTEND = "TestEnd";
+
+
+    public string FileTypeFilter {
+      get { return "Excel 2007 file (*.xlsx)|*.xlsx"; }
+    }
+    public bool Supports(IDataAnalysisSolution solution) {
+      return solution is ISymbolicDataAnalysisSolution &&
+        solution is IRegressionSolution;
+    }
+
+    public void Export(IDataAnalysisSolution solution, string fileName) {
+      var symbSolution = solution as ISymbolicDataAnalysisSolution;
+      if (symbSolution == null) throw new NotSupportedException("This solution cannot be exported to Excel");
+      var formatter = new SymbolicDataAnalysisExpressionExcelFormatter();
+      var formula = formatter.Format(symbSolution.Model.SymbolicExpressionTree, solution.ProblemData.Dataset);
+      ExportChart(fileName, symbSolution, formula);
+    }
+
+    private void ExportChart(string fileName, ISymbolicDataAnalysisSolution solution, string formula) {
+      FileInfo newFile = new FileInfo(fileName);
+      if (newFile.Exists) {
+        newFile.Delete();
+        newFile = new FileInfo(fileName);
+      }
+      var formulaParts = formula.Split(new string[] { Environment.NewLine }, StringSplitOptions.None);
+
+      using (ExcelPackage package = new ExcelPackage(newFile)) {
+        ExcelWorksheet modelWorksheet = package.Workbook.Worksheets.Add("Model");
+        FormatModelSheet(modelWorksheet, solution, formulaParts);
+
+        ExcelWorksheet datasetWorksheet = package.Workbook.Worksheets.Add("Dataset");
+        WriteDatasetToExcel(datasetWorksheet, solution.ProblemData);
+
+        ExcelWorksheet inputsWorksheet = package.Workbook.Worksheets.Add("Inputs");
+        WriteInputSheet(inputsWorksheet, datasetWorksheet, formulaParts.Skip(2), solution.ProblemData.Dataset);
+
+        if (solution is IRegressionSolution) {
+          ExcelWorksheet estimatedWorksheet = package.Workbook.Worksheets.Add("Estimated Values");
+          WriteEstimatedWorksheet(estimatedWorksheet, datasetWorksheet, formulaParts, solution as IRegressionSolution);
+
+          ExcelWorksheet chartsWorksheet = package.Workbook.Worksheets.Add("Charts");
+          AddCharts(chartsWorksheet);
+        }
+        package.Workbook.Properties.Title = "Excel Export";
+        package.Workbook.Properties.Author = "HEAL";
+        package.Workbook.Properties.Comments = "Excel export of a symbolic data analysis solution from HeuristicLab";
+
+        package.Save();
+      }
+    }
+
+    private void FormatModelSheet(ExcelWorksheet modelWorksheet, ISymbolicDataAnalysisSolution solution, IEnumerable<string> formulaParts) {
+      int row = 1;
+      modelWorksheet.Cells[row, 1].Value = "Model";
+      modelWorksheet.Cells[row, 2].Value = solution.Name;
+
+      foreach (var part in formulaParts) {
+        modelWorksheet.Cells[row, 4].Value = part;
+        row++;
+      }
+
+      row = 2;
+      modelWorksheet.Cells[row, 1].Value = "Model Depth";
+      modelWorksheet.Cells[row, 2].Value = solution.Model.SymbolicExpressionTree.Depth;
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Model Length";
+      modelWorksheet.Cells[row, 2].Value = solution.Model.SymbolicExpressionTree.Length;
+      row += 2;
+
+      modelWorksheet.Cells[row, 1].Value = "Estimation Limits Lower";
+      modelWorksheet.Cells[row, 2].Value = Math.Max(solution.Model.LowerEstimationLimit, -9.99999999999999E+307); // minimal value supported by excel
+      modelWorksheet.Names.Add("EstimationLimitLower", modelWorksheet.Cells[row, 2]);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Estimation Limits Upper";
+      modelWorksheet.Cells[row, 2].Value = Math.Min(solution.Model.UpperEstimationLimit, 9.99999999999999E+307);  // maximal value supported by excel
+      modelWorksheet.Names.Add("EstimationLimitUpper", modelWorksheet.Cells[row, 2]);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row += 2;
+
+      modelWorksheet.Cells[row, 1].Value = "Trainings Partition Start";
+      modelWorksheet.Cells[row, 2].Value = solution.ProblemData.TrainingPartition.Start;
+      modelWorksheet.Names.Add(TRAININGSTART, modelWorksheet.Cells[row, 2]);
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Trainings Partition End";
+      modelWorksheet.Cells[row, 2].Value = solution.ProblemData.TrainingPartition.End;
+      modelWorksheet.Names.Add(TRAININGEND, modelWorksheet.Cells[row, 2]);
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Test Partition Start";
+      modelWorksheet.Cells[row, 2].Value = solution.ProblemData.TestPartition.Start;
+      modelWorksheet.Names.Add(TESTSTART, modelWorksheet.Cells[row, 2]);
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Test Partition End";
+      modelWorksheet.Cells[row, 2].Value = solution.ProblemData.TestPartition.End;
+      modelWorksheet.Names.Add(TESTEND, modelWorksheet.Cells[row, 2]);
+      row += 2;
+
+      string excelTrainingTarget = Indirect("B", true);
+      string excelTrainingEstimated = Indirect("C", true);
+      string excelTrainingAbsoluteError = Indirect("D", true);
+      string excelTrainingRelativeError = Indirect("E", true);
+      string excelTrainingMeanError = Indirect("F", true);
+      string excelTrainingMSE = Indirect("G", true);
+
+      string excelTestTarget = Indirect("B", false);
+      string excelTestEstimated = Indirect("C", false);
+      string excelTestAbsoluteError = Indirect("D", false);
+      string excelTestRelativeError = Indirect("E", false);
+      string excelTestMeanError = Indirect("F", false);
+      string excelTestMSE = Indirect("G", false);
+
+      modelWorksheet.Cells[row, 1].Value = "Pearson's R² (training)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("POWER(PEARSON({0},{1}),2)", excelTrainingTarget, excelTrainingEstimated);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Pearson's R² (test)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("POWER(PEARSON({0},{1}),2)", excelTestTarget, excelTestEstimated);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Mean Squared Error (training)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTrainingMSE);
+      modelWorksheet.Names.Add("TrainingMSE", modelWorksheet.Cells[row, 2]);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Mean Squared Error (test)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTestMSE);
+      modelWorksheet.Names.Add("TestMSE", modelWorksheet.Cells[row, 2]);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Mean absolute error (training)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTrainingAbsoluteError);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Mean absolute error (test)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTestAbsoluteError);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Mean error (training)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTrainingMeanError);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Mean error (test)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTestMeanError);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Average relative error (training)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTrainingRelativeError);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.00%";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Average relative error (test)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("AVERAGE({0})", excelTestRelativeError);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.00%";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Normalized Mean Squared error (training)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("TrainingMSE / VAR({0})", excelTrainingTarget);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+      row++;
+
+      modelWorksheet.Cells[row, 1].Value = "Normalized Mean Squared error  (test)";
+      modelWorksheet.Cells[row, 2].Formula = string.Format("TestMSE / VAR({0})", excelTestTarget);
+      modelWorksheet.Cells[row, 2].Style.Numberformat.Format = "0.000E+00";
+
+      modelWorksheet.Cells["A1:B" + row].AutoFitColumns();
+
+      AddModelTreePicture(modelWorksheet, solution.Model);
+    }
+
+    private string Indirect(string column, bool training) {
+      if (training) {
+        return string.Format("INDIRECT(\"'Estimated Values'!{0}\"&{1}+2&\":{0}\"&{2}+1)", column, TRAININGSTART, TRAININGEND);
+      } else {
+        return string.Format("INDIRECT(\"'Estimated Values'!{0}\"&{1}+2&\":{0}\"&{2}+1)", column, TESTSTART, TESTEND);
+      }
+    }
+
+    private void AddCharts(ExcelWorksheet chartsWorksheet) {
+      chartsWorksheet.Names.AddFormula("AllId", "OFFSET('Estimated Values'!$A$1,1,0, COUNTA('Estimated Values'!$A:$A)-1)");
+      chartsWorksheet.Names.AddFormula("AllTarget", "OFFSET('Estimated Values'!$B$1,1,0, COUNTA('Estimated Values'!$B:$B)-1)");
+      chartsWorksheet.Names.AddFormula("AllEstimated", "OFFSET('Estimated Values'!$C$1,1,0, COUNTA('Estimated Values'!$C:$C)-1)");
+      chartsWorksheet.Names.AddFormula("TrainingId", "OFFSET('Estimated Values'!$A$1,Model!TrainingStart + 1,0, Model!TrainingEnd - Model!TrainingStart)");
+      chartsWorksheet.Names.AddFormula("TrainingTarget", "OFFSET('Estimated Values'!$B$1,Model!TrainingStart + 1,0, Model!TrainingEnd - Model!TrainingStart)");
+      chartsWorksheet.Names.AddFormula("TrainingEstimated", "OFFSET('Estimated Values'!$C$1,Model!TrainingStart + 1,0, Model!TrainingEnd - Model!TrainingStart)");
+      chartsWorksheet.Names.AddFormula("TestId", "OFFSET('Estimated Values'!$A$1,Model!TestStart + 1,0, Model!TestEnd - Model!TestStart)");
+      chartsWorksheet.Names.AddFormula("TestTarget", "OFFSET('Estimated Values'!$B$1,Model!TestStart + 1,0, Model!TestEnd - Model!TestStart)");
+      chartsWorksheet.Names.AddFormula("TestEstimated", "OFFSET('Estimated Values'!$C$1,Model!TestStart + 1,0, Model!TestEnd - Model!TestStart)");
+
+      var scatterPlot = chartsWorksheet.Drawings.AddChart("scatterPlot", eChartType.XYScatter);
+      scatterPlot.SetSize(800, 400);
+      scatterPlot.SetPosition(0, 0);
+      scatterPlot.Title.Text = "Scatter Plot";
+      var seriesAll = scatterPlot.Series.Add("AllTarget", "AllEstimated");
+      seriesAll.Header = "All";
+      var seriesTraining = scatterPlot.Series.Add("TrainingTarget", "TrainingEstimated");
+      seriesTraining.Header = "Training";
+      var seriesTest = scatterPlot.Series.Add("TestTarget", "TestEstimated");
+      seriesTest.Header = "Test";
+
+      var lineChart = chartsWorksheet.Drawings.AddChart("lineChart", eChartType.XYScatterLinesNoMarkers);
+      lineChart.SetSize(800, 400);
+      lineChart.SetPosition(400, 0);
+      lineChart.Title.Text = "LineChart";
+      var lineTarget = lineChart.Series.Add("AllTarget", "AllId");
+      lineTarget.Header = "Target";
+      var lineAll = lineChart.Series.Add("AllEstimated", "AllId");
+      lineAll.Header = "All";
+      var lineTraining = lineChart.Series.Add("TrainingEstimated", "TrainingId");
+      lineTraining.Header = "Training";
+      var lineTest = lineChart.Series.Add("TestEstimated", "TestId");
+      lineTest.Header = "Test";
+    }
+
+    private void AddModelTreePicture(ExcelWorksheet modelWorksheet, ISymbolicDataAnalysisModel model) {
+      SymbolicExpressionTreeChart modelTreePicture = new SymbolicExpressionTreeChart();
+      modelTreePicture.Tree = model.SymbolicExpressionTree;
+      string tmpFilename = Path.GetTempFileName();
+      modelTreePicture.Width = 1000;
+      modelTreePicture.Height = 500;
+      modelTreePicture.SaveImageAsEmf(tmpFilename);
+
+      FileInfo fi = new FileInfo(tmpFilename);
+      var excelModelTreePic = modelWorksheet.Drawings.AddPicture("ModelTree", fi);
+      excelModelTreePic.SetSize(50);
+      excelModelTreePic.SetPosition(2, 0, 6, 0);
+    }
+
+    private void WriteEstimatedWorksheet(ExcelWorksheet estimatedWorksheet, ExcelWorksheet datasetWorksheet, string[] formulaParts, IRegressionSolution solution) {
+      string preparedFormula = PrepareFormula(formulaParts);
+      int rows = solution.ProblemData.Dataset.Rows;
+      estimatedWorksheet.Cells[1, 1].Value = "Id";
+      estimatedWorksheet.Cells[1, 2].Value = "Target Variable";
+      estimatedWorksheet.Cells[1, 3].Value = "Estimated Values";
+      estimatedWorksheet.Cells[1, 4].Value = "Absolute Error";
+      estimatedWorksheet.Cells[1, 5].Value = "Relative Error";
+      estimatedWorksheet.Cells[1, 6].Value = "Error";
+      estimatedWorksheet.Cells[1, 7].Value = "Squared Error";
+      estimatedWorksheet.Cells[1, 9].Value = "Unbounded Estimated Values";
+      estimatedWorksheet.Cells[1, 10].Value = "Bounded Estimated Values";
+
+      estimatedWorksheet.Cells[1, 1, 1, 10].AutoFitColumns();
+
+      int targetIndex = solution.ProblemData.Dataset.VariableNames.ToList().FindIndex(x => x.Equals(solution.ProblemData.TargetVariable)) + 1;
+      for (int i = 0; i < rows; i++) {
+        estimatedWorksheet.Cells[i + 2, 1].Value = i;
+        estimatedWorksheet.Cells[i + 2, 2].Formula = datasetWorksheet.Cells[i + 2, targetIndex].FullAddress;
+        estimatedWorksheet.Cells[i + 2, 9].Formula = string.Format(preparedFormula, i + 2);
+      }
+      estimatedWorksheet.Cells["B2:B" + (rows + 1)].Style.Numberformat.Format = "0.000";
+
+      estimatedWorksheet.Cells["C2:C" + (rows + 1)].Formula = "J2";
+      estimatedWorksheet.Cells["C2:C" + (rows + 1)].Style.Numberformat.Format = "0.000";
+      estimatedWorksheet.Cells["D2:D" + (rows + 1)].Formula = "ABS(B2 - C2)";
+      estimatedWorksheet.Cells["D2:D" + (rows + 1)].Style.Numberformat.Format = "0.000";
+      estimatedWorksheet.Cells["E2:E" + (rows + 1)].Formula = "ABS(D2 / B2)";
+      estimatedWorksheet.Cells["E2:E" + (rows + 1)].Style.Numberformat.Format = "0.000";
+      estimatedWorksheet.Cells["F2:F" + (rows + 1)].Formula = "C2 - B2";
+      estimatedWorksheet.Cells["F2:F" + (rows + 1)].Style.Numberformat.Format = "0.000";
+      estimatedWorksheet.Cells["G2:G" + (rows + 1)].Formula = "POWER(F2, 2)";
+      estimatedWorksheet.Cells["G2:G" + (rows + 1)].Style.Numberformat.Format = "0.000";
+
+      estimatedWorksheet.Cells["I2:I" + (rows + 1)].Style.Numberformat.Format = "0.000";
+      estimatedWorksheet.Cells["J2:J" + (rows + 1)].Formula = "IFERROR(IF(I2 > Model!EstimationLimitUpper, Model!EstimationLimitUpper, IF(I2 < Model!EstimationLimitLower, Model!EstimationLimitLower, I2)), AVERAGE(Model!EstimationLimitLower, Model!EstimationLimitUpper))";
+      estimatedWorksheet.Cells["J2:J" + (rows + 1)].Style.Numberformat.Format = "0.000";
+    }
+
+    private string PrepareFormula(string[] formulaParts) {
+      string preparedFormula = formulaParts[0];
+      foreach (var part in formulaParts.Skip(2)) {
+        var varMap = part.Split(new string[] { " = " }, StringSplitOptions.None);
+        var columnName = "$" + varMap[1] + "1";
+        preparedFormula = preparedFormula.Replace(columnName, "Inputs!$" + varMap[1] + "{0}");   //{0} will be replaced later with the row number 
+      }
+      return preparedFormula;
+    }
+
+    private void WriteInputSheet(ExcelWorksheet inputsWorksheet, ExcelWorksheet datasetWorksheet, IEnumerable<string> list, Dataset dataset) {
+      //remark the performance of EPPlus drops dramatically 
+      //if the data is not written row wise (from left to right) due the internal indices used.
+      var variableNames = dataset.VariableNames.Select((v, i) => new { variable = v, index = i + 1 }).ToDictionary(v => v.variable, v => v.index);
+      var nameMapping = list.Select(x => x.Split('=')[0].Trim()).ToArray();
+
+      for (int row = 1; row <= dataset.Rows + 1; row++) {
+        for (int column = 1; column < nameMapping.Length + 1; column++) {
+          int variableIndex = variableNames[nameMapping[column - 1]];
+          inputsWorksheet.Cells[row, column].Formula = datasetWorksheet.Cells[row, variableIndex].FullAddress;
+        }
+      }
+    }
+
+    private void WriteDatasetToExcel(ExcelWorksheet datasetWorksheet, IDataAnalysisProblemData problemData) {
+      //remark the performance of EPPlus drops dramatically 
+      //if the data is not written row wise (from left to right) due the internal indices used.
+      Dataset dataset = problemData.Dataset;
+      var variableNames = dataset.VariableNames.ToList();
+      var doubleVariables = new HashSet<string>(dataset.DoubleVariables);
+
+      for (int col = 1; col <= variableNames.Count; col++)
+        datasetWorksheet.Cells[1, col].Value = variableNames[col - 1];
+
+      for (int row = 0; row < dataset.Rows; row++) {
+        for (int col = 0; col < variableNames.Count; col++) {
+          if (doubleVariables.Contains(variableNames[col]))
+            datasetWorksheet.Cells[row + 2, col + 1].Value = dataset.GetDoubleValue(variableNames[col], row);
+          else
+            datasetWorksheet.Cells[row + 2, col + 1].Value = dataset.GetValue(row, col);
+        }
+      }
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/GraphicalSymbolicDataAnalysisModelView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/GraphicalSymbolicDataAnalysisModelView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/GraphicalSymbolicDataAnalysisModelView.cs	(revision 11010)
@@ -0,0 +1,47 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System.Windows.Forms;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("Graphical Representation")]
+  [Content(typeof(ISymbolicDataAnalysisModel), true)]
+  public partial class GraphicalSymbolicDataAnalysisModelView : AsynchronousContentView {
+    public GraphicalSymbolicDataAnalysisModelView()
+      : base() {
+      InitializeComponent();
+    }
+
+    public new ISymbolicDataAnalysisModel Content {
+      get { return (ISymbolicDataAnalysisModel)base.Content; }
+      set { base.Content = value; }
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      symbolicExpressionTreeView.Content = null;
+      if (Content != null)
+        symbolicExpressionTreeView.Content = Content.SymbolicExpressionTree;
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/GraphicalSymbolicDataAnalysisModelView.designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/GraphicalSymbolicDataAnalysisModelView.designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/GraphicalSymbolicDataAnalysisModelView.designer.cs	(revision 11010)
@@ -0,0 +1,78 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class GraphicalSymbolicDataAnalysisModelView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.symbolicExpressionTreeView = new HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views.GraphicalSymbolicExpressionTreeView();
+      this.SuspendLayout();
+      // 
+      // expressionTreeView
+      // 
+      this.symbolicExpressionTreeView.AllowDrop = true;
+      this.symbolicExpressionTreeView.Caption = "Graphical SymbolicExpressionTree View";
+      this.symbolicExpressionTreeView.Content = null;
+      this.symbolicExpressionTreeView.Dock = System.Windows.Forms.DockStyle.Fill;
+      this.symbolicExpressionTreeView.Location = new System.Drawing.Point(0, 0);
+      this.symbolicExpressionTreeView.Name = "expressionTreeView";
+      this.symbolicExpressionTreeView.ReadOnly = false;
+      this.symbolicExpressionTreeView.Size = new System.Drawing.Size(352, 413);
+      this.symbolicExpressionTreeView.TabIndex = 0;
+      // 
+      // SymbolicExpressionModelView
+      // 
+      this.AllowDrop = true;
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.symbolicExpressionTreeView);
+      this.Name = "SymbolicExpressionModelView";
+      this.Size = new System.Drawing.Size(352, 413);
+      this.ResumeLayout(false);
+
+    }
+
+    #endregion
+    private HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views.GraphicalSymbolicExpressionTreeView symbolicExpressionTreeView;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4.csproj
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4.csproj	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4.csproj	(revision 11010)
@@ -0,0 +1,323 @@
+﻿<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProductVersion>9.0.30729</ProductVersion>
+    <SchemaVersion>2.0</SchemaVersion>
+    <ProjectGuid>{7A2531CE-3F7C-4F13-BCCA-ED6DC27A7086}</ProjectGuid>
+    <OutputType>Library</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>HeuristicLab.Problems.DataAnalysis.Symbolic.Views</RootNamespace>
+    <AssemblyName>HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4</AssemblyName>
+    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
+    <TargetFrameworkProfile>
+    </TargetFrameworkProfile>
+    <FileAlignment>512</FileAlignment>
+    <SignAssembly>true</SignAssembly>
+    <AssemblyOriginatorKeyFile>HeuristicLab.snk</AssemblyOriginatorKeyFile>
+    <FileUpgradeFlags>
+    </FileUpgradeFlags>
+    <OldToolsVersion>3.5</OldToolsVersion>
+    <UpgradeBackupLocation />
+    <PublishUrl>publish\</PublishUrl>
+    <Install>true</Install>
+    <InstallFrom>Disk</InstallFrom>
+    <UpdateEnabled>false</UpdateEnabled>
+    <UpdateMode>Foreground</UpdateMode>
+    <UpdateInterval>7</UpdateInterval>
+    <UpdateIntervalUnits>Days</UpdateIntervalUnits>
+    <UpdatePeriodically>false</UpdatePeriodically>
+    <UpdateRequired>false</UpdateRequired>
+    <MapFileExtensions>true</MapFileExtensions>
+    <ApplicationRevision>0</ApplicationRevision>
+    <ApplicationVersion>1.0.0.%2a</ApplicationVersion>
+    <IsWebBootstrapper>false</IsWebBootstrapper>
+    <UseApplicationTrust>false</UseApplicationTrust>
+    <BootstrapperEnabled>true</BootstrapperEnabled>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>..\..\..\..\trunk\sources\bin\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>..\..\..\..\trunk\sources\bin\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x64' ">
+    <DebugSymbols>true</DebugSymbols>
+    <OutputPath>$(SolutionDir)\bin\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <DebugType>full</DebugType>
+    <PlatformTarget>x64</PlatformTarget>
+    <ErrorReport>prompt</ErrorReport>
+    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x64' ">
+    <OutputPath>$(SolutionDir)\bin\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <Optimize>true</Optimize>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>x64</PlatformTarget>
+    <ErrorReport>prompt</ErrorReport>
+    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x86' ">
+    <DebugSymbols>true</DebugSymbols>
+    <OutputPath>$(SolutionDir)\bin\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <DebugType>full</DebugType>
+    <PlatformTarget>x86</PlatformTarget>
+    <ErrorReport>prompt</ErrorReport>
+    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x86' ">
+    <OutputPath>$(SolutionDir)\bin\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <Optimize>true</Optimize>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>x86</PlatformTarget>
+    <ErrorReport>prompt</ErrorReport>
+    <CodeAnalysisRuleSet>AllRules.ruleset</CodeAnalysisRuleSet>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="ALGLIB-3.7.0, Version=3.7.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <HintPath>..\..\bin\ALGLIB-3.7.0.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="EPPlus-3.1.3, Version=3.1.3.0, Culture=neutral, PublicKeyToken=ea159fdaa78159a1, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\bin\EPPlus-3.1.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Collections-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Collections-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Common-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Common-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Common.Resources-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Common.Resources-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Core-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Core-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Core.Views-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Core.Views-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Data-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Data-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Data.Views-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Data.Views-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Encodings.SymbolicExpressionTreeEncoding-3.4, Version=3.4.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Encodings.SymbolicExpressionTreeEncoding-3.4.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views-3.4, Version=3.4.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views-3.4.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.MainForm-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.MainForm-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.MainForm.WindowsForms-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.MainForm.WindowsForms-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Optimization-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Optimization-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.PluginInfrastructure-3.3, Version=3.3.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.PluginInfrastructure-3.3.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Problems.DataAnalysis-3.4, Version=3.4.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Problems.DataAnalysis-3.4.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="HeuristicLab.Problems.DataAnalysis.Symbolic-3.4, Version=3.4.0.0, Culture=neutral, PublicKeyToken=ba48961d6f65dcec, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\..\..\trunk\sources\bin\HeuristicLab.Problems.DataAnalysis.Symbolic-3.4.dll</HintPath>
+      <Private>False</Private>
+    </Reference>
+    <Reference Include="System" />
+    <Reference Include="System.Core">
+      <RequiredTargetFramework>3.5</RequiredTargetFramework>
+    </Reference>
+    <Reference Include="System.Drawing" />
+    <Reference Include="System.Windows.Forms" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="Exporters\SymbolicSolutionExcelExporter.cs" />
+    <Compile Include="InteractiveSymbolicExpressionTreeChart.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="InteractiveSymbolicExpressionTreeChart.Designer.cs">
+      <DependentUpon>InteractiveSymbolicExpressionTreeChart.cs</DependentUpon>
+    </Compile>
+    <Compile Include="MathSymbolicDataAnalysisModelView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="MathSymbolicDataAnalysisModelView.designer.cs">
+      <DependentUpon>MathSymbolicDataAnalysisModelView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Plugin.cs" />
+    <Compile Include="TextualSymbolicDataAnalysisModelView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="TextualSymbolicDataAnalysisModelView.designer.cs">
+      <DependentUpon>TextualSymbolicDataAnalysisModelView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="InteractiveSymbolicDataAnalysisSolutionSimplifierView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="InteractiveSymbolicDataAnalysisSolutionSimplifierView.Designer.cs">
+      <DependentUpon>InteractiveSymbolicDataAnalysisSolutionSimplifierView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="GraphicalSymbolicDataAnalysisModelView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="GraphicalSymbolicDataAnalysisModelView.designer.cs">
+      <DependentUpon>GraphicalSymbolicDataAnalysisModelView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Symbols\ConstantView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="Symbols\ConstantView.Designer.cs">
+      <DependentUpon>ConstantView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Symbols\LaggedVariableView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="Symbols\LaggedVariableView.Designer.cs">
+      <DependentUpon>LaggedVariableView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Symbols\TimeLagView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="Symbols\TimeLagView.Designer.cs">
+      <DependentUpon>TimeLagView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Symbols\VariableConditionView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="Symbols\VariableConditionView.Designer.cs">
+      <DependentUpon>VariableConditionView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Symbols\VariableView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="Symbols\VariableView.Designer.cs">
+      <DependentUpon>VariableView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="TreeEditDialogs\SymbolicExpressionTreeConstantNodeEditDialog.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="TreeEditDialogs\SymbolicExpressionTreeConstantNodeEditDialog.Designer.cs">
+      <DependentUpon>SymbolicExpressionTreeConstantNodeEditDialog.cs</DependentUpon>
+    </Compile>
+    <Compile Include="TreeEditDialogs\SymbolicExpressionTreeVariableNodeEditDialog.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="TreeEditDialogs\SymbolicExpressionTreeVariableNodeEditDialog.Designer.cs">
+      <DependentUpon>SymbolicExpressionTreeVariableNodeEditDialog.cs</DependentUpon>
+    </Compile>
+    <Compile Include="TreeEditDialogs\SymbolicExpressionTreeNodeInsertDialog.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="TreeEditDialogs\SymbolicExpressionTreeNodeInsertDialog.Designer.cs">
+      <DependentUpon>SymbolicExpressionTreeNodeInsertDialog.cs</DependentUpon>
+    </Compile>
+    <None Include="HeuristicLab.snk" />
+    <None Include="Plugin.cs.frame" />
+    <None Include="Properties\AssemblyInfo.cs.frame" />
+    <Compile Include="RunCollectionVariableImpactView.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="RunCollectionVariableImpactView.Designer.cs">
+      <DependentUpon>RunCollectionVariableImpactView.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Properties\AssemblyInfo.cs" />
+  </ItemGroup>
+  <ItemGroup>
+    <BootstrapperPackage Include="Microsoft.Net.Client.3.5">
+      <Visible>False</Visible>
+      <ProductName>.NET Framework 3.5 SP1 Client Profile</ProductName>
+      <Install>false</Install>
+    </BootstrapperPackage>
+    <BootstrapperPackage Include="Microsoft.Net.Framework.3.5.SP1">
+      <Visible>False</Visible>
+      <ProductName>.NET Framework 3.5 SP1</ProductName>
+      <Install>true</Install>
+    </BootstrapperPackage>
+    <BootstrapperPackage Include="Microsoft.Windows.Installer.3.1">
+      <Visible>False</Visible>
+      <ProductName>Windows Installer 3.1</ProductName>
+      <Install>true</Install>
+    </BootstrapperPackage>
+  </ItemGroup>
+  <ItemGroup>
+    <Content Include="displayModelFrame.html">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </Content>
+  </ItemGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
+       Other similar extension points exist, see Microsoft.Common.targets.
+  <Target Name="BeforeBuild">
+  </Target>
+  <Target Name="AfterBuild">
+  </Target>
+  -->
+  <PropertyGroup>
+    <PreBuildEvent Condition=" '$(OS)' == 'Windows_NT' ">set Path=%25Path%25;$(ProjectDir);$(SolutionDir)
+set ProjectDir=$(ProjectDir)
+set SolutionDir=$(SolutionDir)
+set Outdir=$(Outdir)
+
+call PreBuildEvent.cmd
+</PreBuildEvent>
+    <PreBuildEvent Condition=" '$(OS)' != 'Windows_NT' ">
+export ProjectDir=$(ProjectDir)
+export SolutionDir=$(SolutionDir)
+
+$SolutionDir/PreBuildEvent.sh
+</PreBuildEvent>
+  </PropertyGroup>
+</Project>
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicDataAnalysisSolutionSimplifierView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicDataAnalysisSolutionSimplifierView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicDataAnalysisSolutionSimplifierView.Designer.cs	(revision 11010)
@@ -0,0 +1,243 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class InteractiveSymbolicDataAnalysisSolutionSimplifierView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.components = new System.ComponentModel.Container();
+      this.viewHost = new HeuristicLab.MainForm.WindowsForms.ViewHost();
+      this.splitContainer = new System.Windows.Forms.SplitContainer();
+      this.grpSimplify = new System.Windows.Forms.GroupBox();
+      this.treeStatusValue = new System.Windows.Forms.Label();
+      this.flowLayoutPanel = new System.Windows.Forms.FlowLayoutPanel();
+      this.btnOptimizeConstants = new System.Windows.Forms.Button();
+      this.btnSimplify = new System.Windows.Forms.Button();
+      this.treeStatusLabel = new System.Windows.Forms.Label();
+      this.treeChart = new InteractiveSymbolicExpressionTreeChart();
+      this.grpViewHost = new System.Windows.Forms.GroupBox();
+      ((System.ComponentModel.ISupportInitialize)(this.splitContainer)).BeginInit();
+      this.splitContainer.Panel1.SuspendLayout();
+      this.splitContainer.Panel2.SuspendLayout();
+      this.splitContainer.SuspendLayout();
+      this.grpSimplify.SuspendLayout();
+      this.flowLayoutPanel.SuspendLayout();
+      this.grpViewHost.SuspendLayout();
+      this.SuspendLayout();
+      // 
+      // viewHost
+      // 
+      this.viewHost.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
+            | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.viewHost.Caption = "View";
+      this.viewHost.Content = null;
+      this.viewHost.Enabled = false;
+      this.viewHost.Location = new System.Drawing.Point(6, 16);
+      this.viewHost.Name = "viewHost";
+      this.viewHost.ReadOnly = false;
+      this.viewHost.Size = new System.Drawing.Size(336, 383);
+      this.viewHost.TabIndex = 0;
+      this.viewHost.ViewsLabelVisible = true;
+      this.viewHost.ViewType = null;
+      // 
+      // splitContainer
+      // 
+      this.splitContainer.Dock = System.Windows.Forms.DockStyle.Fill;
+      this.splitContainer.Location = new System.Drawing.Point(0, 0);
+      this.splitContainer.Name = "splitContainer";
+      // 
+      // splitContainer.Panel1
+      // 
+      this.splitContainer.Panel1.Controls.Add(this.grpSimplify);
+      // 
+      // splitContainer.Panel2
+      // 
+      this.splitContainer.Panel2.Controls.Add(this.grpViewHost);
+      this.splitContainer.Size = new System.Drawing.Size(565, 405);
+      this.splitContainer.SplitterDistance = 213;
+      this.splitContainer.TabIndex = 1;
+      // 
+      // grpSimplify
+      // 
+      this.grpSimplify.AutoSize = true;
+      this.grpSimplify.Controls.Add(this.treeStatusValue);
+      this.grpSimplify.Controls.Add(this.flowLayoutPanel);
+      this.grpSimplify.Controls.Add(this.treeStatusLabel);
+      this.grpSimplify.Controls.Add(this.treeChart);
+      this.grpSimplify.Dock = System.Windows.Forms.DockStyle.Fill;
+      this.grpSimplify.Location = new System.Drawing.Point(0, 0);
+      this.grpSimplify.Name = "grpSimplify";
+      this.grpSimplify.Size = new System.Drawing.Size(213, 405);
+      this.grpSimplify.TabIndex = 1;
+      this.grpSimplify.TabStop = false;
+      this.grpSimplify.Text = "Simplify";
+      // 
+      // treeStatusValue
+      // 
+      this.treeStatusValue.AutoSize = true;
+      this.treeStatusValue.BackColor = System.Drawing.Color.Transparent;
+      this.treeStatusValue.ForeColor = System.Drawing.Color.Green;
+      this.treeStatusValue.Location = new System.Drawing.Point(72, 16);
+      this.treeStatusValue.Name = "treeStatusValue";
+      this.treeStatusValue.Size = new System.Drawing.Size(30, 13);
+      this.treeStatusValue.TabIndex = 3;
+      this.treeStatusValue.Text = "Valid";
+      // 
+      // flowLayoutPanel
+      // 
+      this.flowLayoutPanel.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.flowLayoutPanel.Controls.Add(this.btnSimplify);
+      this.flowLayoutPanel.Controls.Add(this.btnOptimizeConstants);
+      this.flowLayoutPanel.Location = new System.Drawing.Point(6, 370);
+      this.flowLayoutPanel.Name = "flowLayoutPanel";
+      this.flowLayoutPanel.Size = new System.Drawing.Size(204, 29);
+      this.flowLayoutPanel.TabIndex = 2;
+      this.flowLayoutPanel.WrapContents = false;
+      // 
+      // btnOptimizeConstants
+      //       
+      this.btnOptimizeConstants.AutoSize = true;
+      this.btnOptimizeConstants.Enabled = false;
+      this.btnOptimizeConstants.Image = HeuristicLab.Common.Resources.VSImageLibrary.Performance;
+      this.btnOptimizeConstants.ImageAlign = System.Drawing.ContentAlignment.MiddleCenter;
+      this.btnOptimizeConstants.Location = new System.Drawing.Point(105, 3);
+      this.btnOptimizeConstants.Name = "btnOptimizeConstants";
+      this.btnOptimizeConstants.Size = new System.Drawing.Size(80, 24);
+      this.btnOptimizeConstants.TabIndex = 2;
+      this.btnOptimizeConstants.Text = "Optimize";
+      this.btnOptimizeConstants.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
+      this.btnOptimizeConstants.TextImageRelation = System.Windows.Forms.TextImageRelation.ImageBeforeText;
+      this.btnOptimizeConstants.UseVisualStyleBackColor = true;
+      this.btnOptimizeConstants.Click += new System.EventHandler(this.btnOptimizeConstants_Click);
+      // 
+      // btnSimplify
+      // 
+      this.btnSimplify.AutoSize = true;
+      this.btnSimplify.Enabled = true;
+      this.btnSimplify.Image = HeuristicLab.Common.Resources.VSImageLibrary.FormulaEvaluator;
+      this.btnSimplify.ImageAlign = System.Drawing.ContentAlignment.MiddleCenter;
+      this.btnSimplify.Location = new System.Drawing.Point(3, 3);
+      this.btnSimplify.Name = "btnSimplify";
+      this.btnSimplify.Size = new System.Drawing.Size(80, 24);
+      this.btnSimplify.TabIndex = 1;
+      this.btnSimplify.Text = "Simplify";
+      this.btnSimplify.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
+      this.btnSimplify.TextImageRelation = System.Windows.Forms.TextImageRelation.ImageBeforeText;
+      this.btnSimplify.UseVisualStyleBackColor = true;
+      this.btnSimplify.Click += new System.EventHandler(this.btnSimplify_Click);
+      // 
+      // treeStatusLabel
+      // 
+      this.treeStatusLabel.AutoSize = true;
+      this.treeStatusLabel.BackColor = System.Drawing.Color.Transparent;
+      this.treeStatusLabel.Location = new System.Drawing.Point(6, 16);
+      this.treeStatusLabel.Name = "treeStatusLabel";
+      this.treeStatusLabel.Size = new System.Drawing.Size(68, 13);
+      this.treeStatusLabel.TabIndex = 2;
+      this.treeStatusLabel.Text = "Tree Status: ";
+      // 
+      // treeChart
+      // 
+      this.treeChart.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
+            | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.treeChart.BackgroundColor = System.Drawing.Color.White;
+      this.treeChart.LineColor = System.Drawing.Color.Black;
+      this.treeChart.Location = new System.Drawing.Point(6, 32);
+      this.treeChart.Name = "treeChart";
+      this.treeChart.Size = new System.Drawing.Size(201, 332);
+      this.treeChart.Spacing = 5;
+      this.treeChart.SuspendRepaint = false;
+      this.treeChart.TabIndex = 0;
+      this.treeChart.TextFont = new System.Drawing.Font("Times New Roman", 8F);
+      this.treeChart.Tree = null;
+      this.treeChart.SymbolicExpressionTreeNodeDoubleClicked += new System.Windows.Forms.MouseEventHandler(this.treeChart_SymbolicExpressionTreeNodeDoubleClicked);
+      // 
+      // grpViewHost
+      // 
+      this.grpViewHost.Controls.Add(this.viewHost);
+      this.grpViewHost.Dock = System.Windows.Forms.DockStyle.Fill;
+      this.grpViewHost.Location = new System.Drawing.Point(0, 0);
+      this.grpViewHost.Name = "grpViewHost";
+      this.grpViewHost.Size = new System.Drawing.Size(348, 405);
+      this.grpViewHost.TabIndex = 1;
+      this.grpViewHost.TabStop = false;
+      this.grpViewHost.Text = "Details";
+      // 
+      // InteractiveSymbolicDataAnalysisSolutionSimplifierView
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+      this.Controls.Add(this.splitContainer);
+      this.DoubleBuffered = true;
+      this.Name = "InteractiveSymbolicDataAnalysisSolutionSimplifierView";
+      this.Size = new System.Drawing.Size(565, 405);
+      this.splitContainer.Panel1.ResumeLayout(false);
+      this.splitContainer.Panel1.PerformLayout();
+      this.splitContainer.Panel2.ResumeLayout(false);
+      ((System.ComponentModel.ISupportInitialize)(this.splitContainer)).EndInit();
+      this.splitContainer.ResumeLayout(false);
+      this.grpSimplify.ResumeLayout(false);
+      this.grpSimplify.PerformLayout();
+      this.flowLayoutPanel.ResumeLayout(false);
+      this.grpViewHost.ResumeLayout(false);
+      this.ResumeLayout(false);
+
+    }
+
+    #endregion
+
+    private InteractiveSymbolicExpressionTreeChart treeChart;
+    private System.Windows.Forms.SplitContainer splitContainer;
+    private HeuristicLab.MainForm.WindowsForms.ViewHost viewHost;
+    private System.Windows.Forms.GroupBox grpSimplify;
+    private System.Windows.Forms.GroupBox grpViewHost;
+    private System.Windows.Forms.Button btnSimplify;
+    private System.Windows.Forms.FlowLayoutPanel flowLayoutPanel;
+    protected System.Windows.Forms.Button btnOptimizeConstants;
+    private System.Windows.Forms.Label treeStatusValue;
+    private System.Windows.Forms.Label treeStatusLabel;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicDataAnalysisSolutionSimplifierView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicDataAnalysisSolutionSimplifierView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicDataAnalysisSolutionSimplifierView.cs	(revision 11010)
@@ -0,0 +1,269 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2012 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+using System.Windows.Forms;
+using HeuristicLab.Common;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  public abstract partial class InteractiveSymbolicDataAnalysisSolutionSimplifierView : AsynchronousContentView {
+    private Dictionary<ISymbolicExpressionTreeNode, ISymbolicExpressionTreeNode> foldedNodes;
+    private Dictionary<ISymbolicExpressionTreeNode, ISymbolicExpressionTreeNode> changedNodes;
+    private Dictionary<ISymbolicExpressionTreeNode, double> nodeImpacts;
+
+    private enum TreeState { Valid, Invalid }
+    private TreeState treeState;
+
+    protected InteractiveSymbolicDataAnalysisSolutionSimplifierView() {
+      InitializeComponent();
+      foldedNodes = new Dictionary<ISymbolicExpressionTreeNode, ISymbolicExpressionTreeNode>();
+      changedNodes = new Dictionary<ISymbolicExpressionTreeNode, ISymbolicExpressionTreeNode>();
+      nodeImpacts = new Dictionary<ISymbolicExpressionTreeNode, double>();
+      this.Caption = "Interactive Solution Simplifier";
+
+      // initialize the tree modifier that will be used to perform edit operations over the tree
+      treeChart.ModifyTree = Modify;
+    }
+
+    /// <summary>
+    /// Remove, Replace or Insert subtrees
+    /// </summary>
+    /// <param name="tree">The symbolic expression tree</param>
+    /// <param name="parent">The insertion point (ie, the parent node who will receive a new child)</param>
+    /// <param name="oldChild">The subtree to be replaced</param>
+    /// <param name="newChild">The replacement subtree</param>
+    /// <param name="removeSubtree">Flag used to indicate if whole subtrees should be removed (default behavior), or just the subtree root</param>
+    private void Modify(ISymbolicExpressionTree tree, ISymbolicExpressionTreeNode parent,
+      ISymbolicExpressionTreeNode oldChild, ISymbolicExpressionTreeNode newChild, bool removeSubtree = true) {
+      if (oldChild == null && newChild == null)
+        throw new ArgumentNullException("Cannot deduce operation type from the arguments. Please provide non null operands.");
+      if (oldChild == null) {
+        // insertion operation
+        parent.AddSubtree(newChild);
+        newChild.Parent = parent;
+      } else if (newChild == null) {
+        // removal operation
+        parent.RemoveSubtree(parent.IndexOfSubtree(oldChild));
+        if (!removeSubtree) {
+          for (int i = oldChild.SubtreeCount - 1; i >= 0; --i) {
+            var subtree = oldChild.GetSubtree(i);
+            oldChild.RemoveSubtree(i);
+            parent.AddSubtree(subtree);
+          }
+        }
+      } else {
+        // replacement operation
+        var replacementIndex = parent.IndexOfSubtree(oldChild);
+        parent.RemoveSubtree(replacementIndex);
+        parent.InsertSubtree(replacementIndex, newChild);
+        newChild.Parent = parent;
+        if (changedNodes.ContainsKey(oldChild)) {
+          changedNodes.Add(newChild, changedNodes[oldChild]); // so that on double click the original node is restored
+          changedNodes.Remove(oldChild);
+        } else {
+          changedNodes.Add(newChild, oldChild);
+        }
+      }
+      treeState = IsValid(tree) ? TreeState.Valid : TreeState.Invalid;
+      switch (treeState) {
+        case TreeState.Valid:
+          this.grpViewHost.Enabled = true;
+          UpdateModel(Content.Model.SymbolicExpressionTree);
+          break;
+        case TreeState.Invalid:
+          this.grpViewHost.Enabled = false;
+          break;
+      }
+    }
+
+    // the optimizer always assumes 2 children for multiplication and addition nodes
+    // thus, we enforce that the tree stays valid so that the constant optimization won't throw an exception
+    // by returning 2 as the minimum allowed arity for addition and multiplication symbols
+    private readonly Func<ISymbol, int> GetMinArity = symbol => {
+      var min = symbol.MinimumArity;
+      if (symbol is Multiplication || symbol is Addition) return Math.Max(2, min);
+      return min;
+    };
+    private bool IsValid(ISymbolicExpressionTree tree) {
+      treeChart.Tree = tree;
+      treeChart.Repaint();
+      bool valid = !tree.IterateNodesPostfix().Any(node => node.SubtreeCount < GetMinArity(node.Symbol) || node.SubtreeCount > node.Symbol.MaximumArity);
+      if (valid) {
+        btnOptimizeConstants.Enabled = true;
+        btnSimplify.Enabled = true;
+        treeStatusValue.Text = "Valid";
+        treeStatusValue.ForeColor = Color.Green;
+      } else {
+        btnOptimizeConstants.Enabled = false;
+        btnSimplify.Enabled = false;
+        treeStatusValue.Text = "Invalid";
+        treeStatusValue.ForeColor = Color.Red;
+      }
+      this.Refresh();
+      return valid;
+    }
+
+    public new ISymbolicDataAnalysisSolution Content {
+      get { return (ISymbolicDataAnalysisSolution)base.Content; }
+      set { base.Content = value; }
+    }
+
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.ModelChanged += Content_Changed;
+      Content.ProblemDataChanged += Content_Changed;
+      treeChart.Repainted += treeChart_Repainted;
+    }
+    protected override void DeregisterContentEvents() {
+      base.DeregisterContentEvents();
+      Content.ModelChanged -= Content_Changed;
+      Content.ProblemDataChanged -= Content_Changed;
+      treeChart.Repainted -= treeChart_Repainted;
+    }
+
+    private void Content_Changed(object sender, EventArgs e) {
+      UpdateView();
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      foldedNodes = new Dictionary<ISymbolicExpressionTreeNode, ISymbolicExpressionTreeNode>();
+      UpdateView();
+      viewHost.Content = this.Content;
+    }
+
+    private void treeChart_Repainted(object sender, EventArgs e) {
+      if (nodeImpacts != null && nodeImpacts.Count > 0)
+        PaintNodeImpacts();
+    }
+
+    private void UpdateView() {
+      if (Content == null || Content.Model == null || Content.ProblemData == null) return;
+      var tree = Content.Model.SymbolicExpressionTree;
+      treeChart.Tree = tree.Root.SubtreeCount > 1 ? new SymbolicExpressionTree(tree.Root) : new SymbolicExpressionTree(tree.Root.GetSubtree(0).GetSubtree(0));
+
+      var impactAndReplacementValues = CalculateImpactAndReplacementValues(tree);
+      var replacementValues = impactAndReplacementValues.ToDictionary(x => x.Key, x => x.Value.Item2);
+      foreach (var pair in replacementValues.Where(pair => !(pair.Key is ConstantTreeNode))) {
+        foldedNodes[pair.Key] = MakeConstantTreeNode(pair.Value);
+      }
+      nodeImpacts = impactAndReplacementValues.ToDictionary(x => x.Key, x => x.Value.Item1);
+      PaintNodeImpacts();
+    }
+
+    protected abstract Dictionary<ISymbolicExpressionTreeNode, double> CalculateReplacementValues(ISymbolicExpressionTree tree);
+    protected abstract Dictionary<ISymbolicExpressionTreeNode, double> CalculateImpactValues(ISymbolicExpressionTree tree);
+    protected abstract Dictionary<ISymbolicExpressionTreeNode, Tuple<double, double>> CalculateImpactAndReplacementValues(ISymbolicExpressionTree tree);
+    protected abstract void UpdateModel(ISymbolicExpressionTree tree);
+
+    private static ConstantTreeNode MakeConstantTreeNode(double value) {
+      var constant = new Constant { MinValue = value - 1, MaxValue = value + 1 };
+      var constantTreeNode = (ConstantTreeNode)constant.CreateTreeNode();
+      constantTreeNode.Value = value;
+      return constantTreeNode;
+    }
+
+    private void treeChart_SymbolicExpressionTreeNodeDoubleClicked(object sender, MouseEventArgs e) {
+      if (treeState == TreeState.Invalid) return;
+      var visualNode = (VisualTreeNode<ISymbolicExpressionTreeNode>)sender;
+      if (visualNode.Content == null) { throw new Exception("VisualNode content cannot be null."); }
+      var symbExprTreeNode = (SymbolicExpressionTreeNode)visualNode.Content;
+      var tree = Content.Model.SymbolicExpressionTree;
+      var parent = symbExprTreeNode.Parent;
+      int indexOfSubtree = parent.IndexOfSubtree(symbExprTreeNode);
+      if (changedNodes.ContainsKey(symbExprTreeNode)) {
+        // undo node change
+        parent.RemoveSubtree(indexOfSubtree);
+        var originalNode = changedNodes[symbExprTreeNode];
+        parent.InsertSubtree(indexOfSubtree, originalNode);
+        changedNodes.Remove(symbExprTreeNode);
+      } else if (foldedNodes.ContainsKey(symbExprTreeNode)) {
+        // undo node folding
+        SwitchNodeWithReplacementNode(parent, indexOfSubtree);
+      }
+      UpdateModel(tree);
+    }
+
+    private void SwitchNodeWithReplacementNode(ISymbolicExpressionTreeNode parent, int subTreeIndex) {
+      ISymbolicExpressionTreeNode subTree = parent.GetSubtree(subTreeIndex);
+      if (foldedNodes.ContainsKey(subTree)) {
+        parent.RemoveSubtree(subTreeIndex);
+        var replacementNode = foldedNodes[subTree];
+        parent.InsertSubtree(subTreeIndex, replacementNode);
+        // exchange key and value 
+        foldedNodes.Remove(subTree);
+        foldedNodes.Add(replacementNode, subTree);
+      }
+    }
+
+    private void PaintNodeImpacts() {
+      var impacts = nodeImpacts.Values;
+      double max = impacts.Max();
+      double min = impacts.Min();
+      foreach (ISymbolicExpressionTreeNode treeNode in Content.Model.SymbolicExpressionTree.IterateNodesPostfix()) {
+        VisualTreeNode<ISymbolicExpressionTreeNode> visualTree = treeChart.GetVisualSymbolicExpressionTreeNode(treeNode);
+
+        if (!(treeNode is ConstantTreeNode) && nodeImpacts.ContainsKey(treeNode)) {
+          double impact = nodeImpacts[treeNode];
+
+          // impact = 0 if no change
+          // impact < 0 if new solution is better
+          // impact > 0 if new solution is worse
+          if (impact < 0.0) {
+            // min is guaranteed to be < 0
+            visualTree.FillColor = Color.FromArgb((int)(impact / min * 255), Color.Red);
+          } else if (impact.IsAlmost(0.0)) {
+            visualTree.FillColor = Color.White;
+          } else {
+            // max is guaranteed to be > 0
+            visualTree.FillColor = Color.FromArgb((int)(impact / max * 255), Color.Green);
+          }
+          visualTree.ToolTip += Environment.NewLine + "Node impact: " + impact;
+          var constantReplacementNode = foldedNodes[treeNode] as ConstantTreeNode;
+          if (constantReplacementNode != null) {
+            visualTree.ToolTip += Environment.NewLine + "Replacement value: " + constantReplacementNode.Value;
+          }
+        }
+        if (visualTree != null)
+          if (changedNodes.ContainsKey(treeNode)) {
+            visualTree.LineColor = Color.DodgerBlue;
+          } else if (treeNode is ConstantTreeNode && foldedNodes.ContainsKey(treeNode)) {
+            visualTree.LineColor = Color.DarkOrange;
+          }
+      }
+      treeChart.RepaintNodes();
+    }
+
+    private void btnSimplify_Click(object sender, EventArgs e) {
+      var simplifier = new SymbolicDataAnalysisExpressionTreeSimplifier();
+      var simplifiedExpressionTree = simplifier.Simplify(Content.Model.SymbolicExpressionTree);
+      UpdateModel(simplifiedExpressionTree);
+    }
+
+    protected abstract void btnOptimizeConstants_Click(object sender, EventArgs e);
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicExpressionTreeChart.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicExpressionTreeChart.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicExpressionTreeChart.Designer.cs	(revision 11010)
@@ -0,0 +1,157 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System.Windows.Forms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class InteractiveSymbolicExpressionTreeChart {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.insertNodeToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.changeNodeToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.cutToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.removeToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.removeNodeToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.removeSubtreeToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.pasteToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.toolStripSeparator = new System.Windows.Forms.ToolStripSeparator();
+      this.copyToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
+      this.SuspendLayout();
+      // 
+      // insertNodeToolStripMenuItem
+      // 
+      this.insertNodeToolStripMenuItem.Name = "insertNodeToolStripMenuItem";
+      this.insertNodeToolStripMenuItem.Size = new System.Drawing.Size(147, 22);
+      this.insertNodeToolStripMenuItem.Text = "Insert Node";
+      this.insertNodeToolStripMenuItem.Click += new System.EventHandler(this.insertNodeToolStripMenuItem_Click);
+      // 
+      // changeNodeToolStripMenuItem
+      // 
+      this.changeNodeToolStripMenuItem.Name = "changeNodeToolStripMenuItem";
+      this.changeNodeToolStripMenuItem.Size = new System.Drawing.Size(147, 22);
+      this.changeNodeToolStripMenuItem.Text = "Change Node";
+      this.changeNodeToolStripMenuItem.Click += new System.EventHandler(this.changeNodeToolStripMenuItem_Click);
+      // 
+      // cutToolStripMenuItem
+      // 
+      this.cutToolStripMenuItem.Name = "cutToolStripMenuItem";
+      this.cutToolStripMenuItem.Size = new System.Drawing.Size(147, 22);
+      this.cutToolStripMenuItem.Text = "Cut";
+      this.cutToolStripMenuItem.Click += new System.EventHandler(this.cutToolStripMenuItem_Click);
+      // 
+      // removeToolStripMenuItem
+      // 
+      this.removeToolStripMenuItem.DropDownItems.AddRange(new System.Windows.Forms.ToolStripItem[] {
+            this.removeNodeToolStripMenuItem,
+            this.removeSubtreeToolStripMenuItem});
+      this.removeToolStripMenuItem.Name = "removeToolStripMenuItem";
+      this.removeToolStripMenuItem.Size = new System.Drawing.Size(147, 22);
+      this.removeToolStripMenuItem.Text = "Remove";
+      this.removeToolStripMenuItem.Click += new System.EventHandler(this.removeSubtreeToolStripMenuItem_Click);
+      // 
+      // removeNodeToolStripMenuItem
+      // 
+      this.removeNodeToolStripMenuItem.Name = "removeNodeToolStripMenuItem";
+      this.removeNodeToolStripMenuItem.Size = new System.Drawing.Size(114, 22);
+      this.removeNodeToolStripMenuItem.Text = "Node";
+      this.removeNodeToolStripMenuItem.Click += new System.EventHandler(this.removeNodeToolStripMenuItem_Click);
+      // 
+      // removeSubtreeToolStripMenuItem
+      // 
+      this.removeSubtreeToolStripMenuItem.Name = "removeSubtreeToolStripMenuItem";
+      this.removeSubtreeToolStripMenuItem.Size = new System.Drawing.Size(114, 22);
+      this.removeSubtreeToolStripMenuItem.Text = "Subtree";
+      this.removeSubtreeToolStripMenuItem.Click += new System.EventHandler(this.removeSubtreeToolStripMenuItem_Click);
+      // 
+      // pasteToolStripMenuItem
+      // 
+      this.pasteToolStripMenuItem.Name = "pasteToolStripMenuItem";
+      this.pasteToolStripMenuItem.Size = new System.Drawing.Size(147, 22);
+      this.pasteToolStripMenuItem.Text = "Paste";
+      this.pasteToolStripMenuItem.Click += new System.EventHandler(this.pasteToolStripMenuItem_Clicked);
+      // 
+      // toolStripSeparator
+      // 
+      this.toolStripSeparator.Name = "toolStripSeparator";
+      this.toolStripSeparator.Size = new System.Drawing.Size(149, 6);
+      // 
+      // copyToolStripMenuItem
+      // 
+      this.copyToolStripMenuItem.Name = "copyToolStripMenuItem";
+      this.copyToolStripMenuItem.Size = new System.Drawing.Size(147, 22);
+      this.copyToolStripMenuItem.Text = "Copy";
+      this.copyToolStripMenuItem.Click += new System.EventHandler(this.copyToolStripMenuItem_Click);
+      //
+      // contextMenuStrip
+      //
+      this.contextMenuStrip.Opened += this.contextMenuStrip_Opened;
+      this.contextMenuStrip.Items.AddRange(new ToolStripItem[] { insertNodeToolStripMenuItem, 
+                                                                 changeNodeToolStripMenuItem, 
+                                                                 copyToolStripMenuItem, 
+                                                                 cutToolStripMenuItem, 
+                                                                 removeToolStripMenuItem, 
+                                                                 pasteToolStripMenuItem });
+      // 
+      // InteractiveSymbolicExpressionTreeChart
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+      this.DoubleBuffered = true;
+      this.Name = "InteractiveSymbolicExpressionTreeChart";
+      this.ResumeLayout(false);
+
+    }
+
+    private ToolStripMenuItem insertNodeToolStripMenuItem;
+    private ToolStripMenuItem changeNodeToolStripMenuItem;
+    private ToolStripMenuItem cutToolStripMenuItem;
+    private ToolStripMenuItem pasteToolStripMenuItem;
+    private ToolStripMenuItem removeToolStripMenuItem;
+    private ToolStripMenuItem removeNodeToolStripMenuItem;
+    private ToolStripMenuItem removeSubtreeToolStripMenuItem;
+
+    #endregion
+
+    private ToolStripSeparator toolStripSeparator;
+    private ToolStripMenuItem copyToolStripMenuItem;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicExpressionTreeChart.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicExpressionTreeChart.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/InteractiveSymbolicExpressionTreeChart.cs	(revision 11010)
@@ -0,0 +1,234 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Drawing;
+using System.Linq;
+using System.Windows.Forms;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  internal delegate void
+  ModifyTree(ISymbolicExpressionTree tree, ISymbolicExpressionTreeNode node, ISymbolicExpressionTreeNode oldChild, ISymbolicExpressionTreeNode newChild, bool removeSubtree = true);
+
+  internal sealed partial class InteractiveSymbolicExpressionTreeChart : SymbolicExpressionTreeChart {
+    private ISymbolicExpressionTreeNode tempNode; // node in clipboard (to be cut/copy/pasted etc)
+    private VisualTreeNode<ISymbolicExpressionTreeNode> currSelected; // currently selected node
+    private enum EditOp { NoOp, CopySubtree, CutSubtree }
+    private EditOp lastOp = EditOp.NoOp;
+
+    // delegate to notify the parent container (the view) about the tree edit operations that it needs to perform
+    public ModifyTree ModifyTree { get; set; }
+
+    public InteractiveSymbolicExpressionTreeChart() {
+      InitializeComponent();
+      currSelected = null;
+      tempNode = null;
+    }
+
+    private void contextMenuStrip_Opened(object sender, EventArgs e) {
+      var menuStrip = (ContextMenuStrip)sender;
+      var point = menuStrip.SourceControl.PointToClient(Cursor.Position);
+      var ea = new MouseEventArgs(MouseButtons.Left, 1, point.X, point.Y, 0);
+      var visualNode = FindVisualSymbolicExpressionTreeNodeAt(ea.X, ea.Y);
+      if (visualNode != null) {
+        OnSymbolicExpressionTreeNodeClicked(visualNode, ea);
+      } else {
+        currSelected = null;
+      }
+
+      if (currSelected == null) {
+        insertNodeToolStripMenuItem.Visible = false;
+        changeNodeToolStripMenuItem.Visible = false;
+        copyToolStripMenuItem.Visible = false;
+        cutToolStripMenuItem.Visible = false;
+        removeToolStripMenuItem.Visible = false;
+        pasteToolStripMenuItem.Visible = false;
+      } else {
+        var node = currSelected.Content;
+        insertNodeToolStripMenuItem.Visible = true;
+        changeNodeToolStripMenuItem.Visible = true;
+        changeNodeToolStripMenuItem.Enabled = (node is SymbolicExpressionTreeTerminalNode);
+        insertNodeToolStripMenuItem.Enabled = !changeNodeToolStripMenuItem.Enabled;
+        copyToolStripMenuItem.Visible = true;
+        cutToolStripMenuItem.Visible = true;
+        removeToolStripMenuItem.Visible = true;
+
+        pasteToolStripMenuItem.Visible = true;
+        pasteToolStripMenuItem.Enabled = tempNode != null && insertNodeToolStripMenuItem.Enabled
+                                                          && !(lastOp == EditOp.CutSubtree
+                                                          && tempNode.IterateNodesBreadth().Contains(currSelected.Content));
+      }
+    }
+
+    protected override void OnSymbolicExpressionTreeNodeClicked(object sender, MouseEventArgs e) {
+      currSelected = (VisualTreeNode<ISymbolicExpressionTreeNode>)sender; ;
+      if (currSelected != null) {
+        currSelected.LineColor = Color.FromArgb(130, currSelected.LineColor);
+        RepaintNode(currSelected);
+      }
+      base.OnSymbolicExpressionTreeNodeClicked(sender, e);
+    }
+
+    protected override void SymbolicExpressionTreeChart_MouseClick(object sender, MouseEventArgs e) {
+      if (currSelected != null) {
+        currSelected.LineColor = Color.FromArgb(255, currSelected.LineColor);
+        RepaintNode(currSelected);
+      }
+      base.SymbolicExpressionTreeChart_MouseClick(sender, e);
+    }
+
+    protected override void OnSymbolicExpressionTreeNodeDoubleClicked(object sender, MouseEventArgs e) {
+      currSelected = null;
+      base.OnSymbolicExpressionTreeNodeDoubleClicked(sender, e);
+    }
+
+    private void insertNodeToolStripMenuItem_Click(object sender, EventArgs e) {
+      if (currSelected == null || currSelected.Content is SymbolicExpressionTreeTerminalNode) return;
+      var parent = currSelected.Content;
+
+      using (var dialog = new InsertNodeDialog()) {
+        dialog.SetAllowedSymbols(parent.Grammar.AllowedSymbols.Where(s => s.Enabled && s.InitialFrequency > 0.0 && !(s is ProgramRootSymbol || s is StartSymbol || s is Defun)));
+        dialog.ShowDialog(this);
+        if (dialog.DialogResult != DialogResult.OK) return;
+
+        var symbol = dialog.SelectedSymbol();
+        var node = symbol.CreateTreeNode();
+        if (node is ConstantTreeNode) {
+          var constant = node as ConstantTreeNode;
+          constant.Value = double.Parse(dialog.constantValueTextBox.Text);
+        } else if (node is VariableTreeNode) {
+          var variable = node as VariableTreeNode;
+          variable.Weight = double.Parse(dialog.variableWeightTextBox.Text);
+          variable.VariableName = dialog.variableNamesCombo.Text;
+        } else if (node.Symbol.MinimumArity <= parent.SubtreeCount && node.Symbol.MaximumArity >= parent.SubtreeCount) {
+          for (int i = parent.SubtreeCount - 1; i >= 0; --i) {
+            var child = parent.GetSubtree(i);
+            parent.RemoveSubtree(i);
+            node.AddSubtree(child);
+          }
+        }
+        // the if condition will always be true for the final else clause above
+        if (parent.Symbol.MaximumArity > parent.SubtreeCount) {
+          ModifyTree(Tree, parent, null, node);
+        }
+      }
+      currSelected = null;
+    }
+    private void changeNodeToolStripMenuItem_Click(object sender, EventArgs e) {
+      if (currSelected == null) return;
+
+      var node = (ISymbolicExpressionTreeNode)currSelected.Content.Clone();
+      var originalNode = currSelected.Content;
+
+      ISymbolicExpressionTreeNode newNode = null;
+      var result = DialogResult.Cancel;
+      if (node is ConstantTreeNode) {
+        using (var dialog = new ConstantNodeEditDialog(node)) {
+          dialog.ShowDialog(this);
+          newNode = dialog.NewNode;
+          result = dialog.DialogResult;
+        }
+      } else if (node is VariableTreeNode) {
+        using (var dialog = new VariableNodeEditDialog(node)) {
+          dialog.ShowDialog(this);
+          newNode = dialog.NewNode;
+          result = dialog.DialogResult;
+        }
+      }
+      if (result != DialogResult.OK) return;
+      ModifyTree(Tree, originalNode.Parent, originalNode, newNode); // this will replace the original node with the new node
+      currSelected = null;
+    }
+    private void cutToolStripMenuItem_Click(object sender, EventArgs e) {
+      lastOp = EditOp.CutSubtree;
+      copySubtree();
+    }
+    private void copyToolStripMenuItem_Click(object sender, EventArgs e) {
+      lastOp = EditOp.CopySubtree;
+      copySubtree();
+    }
+    private void copySubtree() {
+      if (tempNode != null) {
+        foreach (var subtree in tempNode.IterateNodesPostfix()) {
+          var visualNode = GetVisualSymbolicExpressionTreeNode(subtree);
+          visualNode.LineColor = Color.FromArgb(255, visualNode.LineColor); // reset the alpha value to 255
+          visualNode.TextColor = Color.FromArgb(255, visualNode.TextColor);
+          if (subtree.Parent != null) {
+            var visualLine = GetVisualSymbolicExpressionTreeNodeConnection(subtree.Parent, subtree);
+            visualLine.LineColor = Color.FromArgb(255, visualLine.LineColor);
+          }
+        }
+      }
+      tempNode = currSelected.Content;
+      foreach (var node in tempNode.IterateNodesPostfix()) {
+        var visualNode = GetVisualSymbolicExpressionTreeNode(node);
+        visualNode.LineColor = Color.FromArgb(100, visualNode.LineColor);
+        visualNode.TextColor = Color.FromArgb(100, visualNode.TextColor);
+        foreach (var subtree in node.Subtrees) {
+          var visualLine = GetVisualSymbolicExpressionTreeNodeConnection(node, subtree);
+          visualLine.LineColor = Color.FromArgb(100, visualLine.LineColor);
+        }
+      }
+      currSelected = null;
+      Repaint();
+    }
+    private void removeNodeToolStripMenuItem_Click(object sender, EventArgs e) {
+      var node = currSelected.Content;
+      if (node == tempNode) tempNode = null;
+      ModifyTree(Tree, node.Parent, node, null, removeSubtree: false);
+      currSelected = null; // because the currently selected node was just deleted
+    }
+    private void removeSubtreeToolStripMenuItem_Click(object sender, EventArgs e) {
+      var node = currSelected.Content;
+      if (node.IterateNodesPostfix().Contains(tempNode)) tempNode = null;
+      ModifyTree(Tree, node.Parent, node, null, removeSubtree: true);
+      currSelected = null; // because the currently selected node was just deleted
+      contextMenuStrip.Close(); // avoid display of submenus since the action has already been performed
+    }
+    private void pasteToolStripMenuItem_Clicked(object sender, EventArgs e) {
+      if (!(lastOp == EditOp.CopySubtree || lastOp == EditOp.CutSubtree)) return;
+      // check if the copied/cut node (stored in the tempNode) can be inserted as a child of the current selected node
+      var node = currSelected.Content;
+      if (node is ConstantTreeNode || node is VariableTreeNode) return;
+      // check if the currently selected node can accept the copied node as a child 
+      // no need to check the grammar, an arity check will do just fine here
+      if (node.Symbol.MaximumArity <= node.SubtreeCount) return;
+      switch (lastOp) {
+        case EditOp.CutSubtree: {
+            if (tempNode.IterateNodesBreadth().Contains(node))
+              throw new ArgumentException();// cannot cut/paste a node into itself
+            ModifyTree(Tree, tempNode.Parent, tempNode, null); //remove node from its original parent
+            ModifyTree(Tree, node, null, tempNode); //insert it as a child to the new parent 
+            break;
+          }
+        case EditOp.CopySubtree: {
+            var clone = (SymbolicExpressionTreeNode)tempNode.Clone();
+            ModifyTree(Tree, node, null, clone);
+            break;
+          }
+      }
+      currSelected = null; // because the tree will have changed
+      tempNode = null; // clear the clipboard after one paste
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/MathSymbolicDataAnalysisModelView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/MathSymbolicDataAnalysisModelView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/MathSymbolicDataAnalysisModelView.cs	(revision 11010)
@@ -0,0 +1,70 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.IO;
+using System.Windows.Forms;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("Mathematical Representation")]
+  [Content(typeof(ISymbolicDataAnalysisModel))]
+  public partial class MathSymbolicDataAnalysisModelView : AsynchronousContentView {
+    private SymbolicDataAnalysisExpressionLatexFormatter formatter = new SymbolicDataAnalysisExpressionLatexFormatter();
+    public MathSymbolicDataAnalysisModelView()
+      : base() {
+      InitializeComponent();
+      webBrowser.ScrollBarsEnabled = true;
+      webBrowser.ScriptErrorsSuppressed = false;
+
+      // update for the first time after page has loaded
+      webBrowser.DocumentCompleted += (sender, args) => RefreshHtmlPage();
+
+      string hlDir = Path.GetFullPath(AppDomain.CurrentDomain.BaseDirectory);
+      webBrowser.Navigate("file://" + Path.Combine(hlDir, "displayModelFrame.html"));
+    }
+
+    public new ISymbolicDataAnalysisModel Content {
+      get { return (ISymbolicDataAnalysisModel)base.Content; }
+      set { base.Content = value; }
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      RefreshHtmlPage();
+    }
+
+    private void RefreshHtmlPage() {
+      // only update if the page has loaded already
+      if (webBrowser.Document == null || webBrowser.Document.Body == null) return;
+
+      if (Content != null) {
+        HtmlElement newElement = webBrowser.Document.GetElementById("model");
+        newElement.InnerText = formatter.Format(Content.SymbolicExpressionTree);
+      } else {
+        HtmlElement newElement = webBrowser.Document.GetElementById("model");
+        newElement.InnerText = string.Empty;
+      }
+      webBrowser.Document.InvokeScript("refreshModel");
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/MathSymbolicDataAnalysisModelView.designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/MathSymbolicDataAnalysisModelView.designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/MathSymbolicDataAnalysisModelView.designer.cs	(revision 11010)
@@ -0,0 +1,81 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class MathSymbolicDataAnalysisModelView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        webBrowser.Dispose();
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.webBrowser = new System.Windows.Forms.WebBrowser();
+      this.SuspendLayout();
+      // 
+      // webBrowser
+      // 
+      this.webBrowser.AllowNavigation = false;
+      this.webBrowser.AllowWebBrowserDrop = false;
+      this.webBrowser.Dock = System.Windows.Forms.DockStyle.Fill;
+      this.webBrowser.IsWebBrowserContextMenuEnabled = false;
+      this.webBrowser.Location = new System.Drawing.Point(0, 0);
+      this.webBrowser.MinimumSize = new System.Drawing.Size(20, 20);
+      this.webBrowser.Name = "webBrowser";
+      this.webBrowser.Size = new System.Drawing.Size(352, 413);
+      this.webBrowser.TabIndex = 0;
+      this.webBrowser.WebBrowserShortcutsEnabled = false;
+      // 
+      // MathSymbolicDataAnalysisModelView
+      // 
+      this.AllowDrop = true;
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.webBrowser);
+      this.Name = "MathSymbolicDataAnalysisModelView";
+      this.Size = new System.Drawing.Size(352, 413);
+      this.ResumeLayout(false);
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.WebBrowser webBrowser;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Plugin.cs.frame
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Plugin.cs.frame	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Plugin.cs.frame	(revision 11010)
@@ -0,0 +1,50 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+using HeuristicLab.PluginInfrastructure;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [Plugin("HeuristicLab.Problems.DataAnalysis.Symbolic.Views","Provides views for symbolic data analysis problem classes.", "3.4.5.$WCREV$")]
+  [PluginFile("HeuristicLab.Problems.DataAnalysis.Symbolic.Views-3.4.dll", PluginFileType.Assembly)]
+  [PluginFile("displayModelFrame.html", PluginFileType.Data)]
+  [PluginDependency("HeuristicLab.ALGLIB", "3.7.0")]
+  [PluginDependency("HeuristicLab.Collections", "3.3")]
+  [PluginDependency("HeuristicLab.Common", "3.3")]
+  [PluginDependency("HeuristicLab.Common.Resources", "3.3")]
+  [PluginDependency("HeuristicLab.Core", "3.3")]
+  [PluginDependency("HeuristicLab.Core.Views", "3.3")]
+  [PluginDependency("HeuristicLab.Data", "3.3")]
+  [PluginDependency("HeuristicLab.Data.Views", "3.3")]
+  [PluginDependency("HeuristicLab.EPPlus", "3.1")]
+  [PluginDependency("HeuristicLab.Encodings.SymbolicExpressionTreeEncoding", "3.4")]
+  [PluginDependency("HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views", "3.4")]
+  [PluginDependency("HeuristicLab.MainForm", "3.3")]
+  [PluginDependency("HeuristicLab.MainForm.WindowsForms", "3.3")]
+  [PluginDependency("HeuristicLab.MathJax", "1.1")]
+  [PluginDependency("HeuristicLab.Optimization","3.3")]
+  [PluginDependency("HeuristicLab.Problems.DataAnalysis", "3.4")]
+  [PluginDependency("HeuristicLab.Problems.DataAnalysis.Symbolic", "3.4")]
+  public class HeuristicLabProblemsDataAnalysisSymbolicViewsPlugin : PluginBase {
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Properties/AssemblyInfo.cs.frame
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Properties/AssemblyInfo.cs.frame	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Properties/AssemblyInfo.cs.frame	(revision 11010)
@@ -0,0 +1,55 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System.Reflection;
+using System.Runtime.InteropServices;
+
+// General Information about an assembly is controlled through the following 
+// set of attributes. Change these attribute values to modify the information
+// associated with an assembly.
+[assembly: AssemblyTitle("HeuristicLab.Problems.DataAnalysis.Symbolic.Views")]
+[assembly: AssemblyDescription("Provides views for symbolic data analysis problem classes.")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("")]
+[assembly: AssemblyProduct("HeuristicLab")]
+[assembly: AssemblyCopyright("(c) 2002-2013 HEAL")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+
+// Setting ComVisible to false makes the types in this assembly not visible 
+// to COM components.  If you need to access a type in this assembly from 
+// COM, set the ComVisible attribute to true on that type.
+[assembly: ComVisible(false)]
+
+// The following GUID is for the ID of the typelib if this project is exposed to COM
+[assembly: Guid("B2F2EF94-C278-4DCB-B8AB-E0C22A95F747")]
+
+// Version information for an assembly consists of the following four values:
+//
+//      Major Version
+//      Minor Version 
+//      Build Number
+//      Revision
+//
+// You can specify all the values or you can default the Revision and Build Numbers 
+// by using the '*' as shown below:
+[assembly: AssemblyVersion("3.4.0.0")]
+[assembly: AssemblyFileVersion("3.4.5.$WCREV$")]
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/RunCollectionVariableImpactView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/RunCollectionVariableImpactView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/RunCollectionVariableImpactView.Designer.cs	(revision 11010)
@@ -0,0 +1,122 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class RunCollectionVariableImpactView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.matrixView = new HeuristicLab.Data.Views.StringConvertibleMatrixView();
+      this.comboBox = new System.Windows.Forms.ComboBox();
+      this.foldsLabel = new System.Windows.Forms.Label();
+      this.variableImpactsGroupBox = new System.Windows.Forms.GroupBox();
+      this.variableImpactsGroupBox.SuspendLayout();
+      this.SuspendLayout();
+      // 
+      // matrixView
+      // 
+      this.matrixView.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
+            | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.matrixView.Caption = "StringConvertibleMatrix View";
+      this.matrixView.Content = null;
+      this.matrixView.Location = new System.Drawing.Point(6, 19);
+      this.matrixView.Name = "matrixView";
+      this.matrixView.ReadOnly = true;
+      this.matrixView.ShowRowsAndColumnsTextBox = true;
+      this.matrixView.ShowStatisticalInformation = true;
+      this.matrixView.Size = new System.Drawing.Size(294, 174);
+      this.matrixView.TabIndex = 0;
+      // 
+      // comboBox
+      // 
+      this.comboBox.FormattingEnabled = true;
+      this.comboBox.Location = new System.Drawing.Point(39, 6);
+      this.comboBox.Name = "comboBox";
+      this.comboBox.Size = new System.Drawing.Size(68, 21);
+      this.comboBox.TabIndex = 1;
+      this.comboBox.SelectedValueChanged += new System.EventHandler(this.comboBox_SelectedValueChanged);
+      // 
+      // label1
+      // 
+      this.foldsLabel.AutoSize = true;
+      this.foldsLabel.Location = new System.Drawing.Point(3, 9);
+      this.foldsLabel.Name = "foldsLabel";
+      this.foldsLabel.Size = new System.Drawing.Size(30, 13);
+      this.foldsLabel.TabIndex = 2;
+      this.foldsLabel.Text = "Fold:";
+      // 
+      // variableImpactsGroupBox
+      // 
+      this.variableImpactsGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
+            | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.variableImpactsGroupBox.Controls.Add(this.matrixView);
+      this.variableImpactsGroupBox.Location = new System.Drawing.Point(0, 33);
+      this.variableImpactsGroupBox.Name = "variableImpactsGroupBox";
+      this.variableImpactsGroupBox.Size = new System.Drawing.Size(306, 199);
+      this.variableImpactsGroupBox.TabIndex = 3;
+      this.variableImpactsGroupBox.TabStop = false;
+      this.variableImpactsGroupBox.Text = "Variable impacts:";
+      // 
+      // RunCollectionVariableImpactView
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.variableImpactsGroupBox);
+      this.Controls.Add(this.foldsLabel);
+      this.Controls.Add(this.comboBox);
+      this.Name = "RunCollectionVariableImpactView";
+      this.Size = new System.Drawing.Size(309, 235);
+      this.variableImpactsGroupBox.ResumeLayout(false);
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private HeuristicLab.Data.Views.StringConvertibleMatrixView matrixView;
+    private System.Windows.Forms.ComboBox comboBox;
+    private System.Windows.Forms.Label foldsLabel;
+    private System.Windows.Forms.GroupBox variableImpactsGroupBox;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/RunCollectionVariableImpactView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/RunCollectionVariableImpactView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/RunCollectionVariableImpactView.cs	(revision 11010)
@@ -0,0 +1,356 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+using System.Windows.Forms;
+using HeuristicLab.Common;
+using HeuristicLab.Data;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+using HeuristicLab.Optimization;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [Content(typeof(RunCollection), false)]
+  [View("Variable Impacts")]
+  public sealed partial class RunCollectionVariableImpactView : AsynchronousContentView {
+    private const string variableImpactResultName = "Variable impacts";
+    private const string crossValidationFoldsResultName = "CrossValidation Folds";
+    private const string numberOfFoldsParameterName = "Folds";
+    public RunCollectionVariableImpactView() {
+      InitializeComponent();
+    }
+
+    public new RunCollection Content {
+      get { return (RunCollection)base.Content; }
+      set { base.Content = value; }
+    }
+
+    #region events
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.UpdateOfRunsInProgressChanged += Content_UpdateOfRunsInProgressChanged;
+      Content.ItemsAdded += Content_ItemsAdded;
+      Content.ItemsRemoved += Content_ItemsRemoved;
+      Content.CollectionReset += Content_CollectionReset;
+      RegisterRunEvents(Content);
+    }
+    protected override void DeregisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.UpdateOfRunsInProgressChanged -= Content_UpdateOfRunsInProgressChanged;
+      Content.ItemsAdded -= Content_ItemsAdded;
+      Content.ItemsRemoved -= Content_ItemsRemoved;
+      Content.CollectionReset -= Content_CollectionReset;
+      DeregisterRunEvents(Content);
+    }
+    private void RegisterRunEvents(IEnumerable<IRun> runs) {
+      foreach (IRun run in runs)
+        run.Changed += Run_Changed;
+    }
+    private void DeregisterRunEvents(IEnumerable<IRun> runs) {
+      foreach (IRun run in runs)
+        run.Changed -= Run_Changed;
+    }
+    private void Content_ItemsAdded(object sender, HeuristicLab.Collections.CollectionItemsChangedEventArgs<IRun> e) {
+      RegisterRunEvents(e.Items);
+      UpdateData();
+    }
+    private void Content_ItemsRemoved(object sender, HeuristicLab.Collections.CollectionItemsChangedEventArgs<IRun> e) {
+      DeregisterRunEvents(e.Items);
+      UpdateData();
+    }
+    private void Content_CollectionReset(object sender, HeuristicLab.Collections.CollectionItemsChangedEventArgs<IRun> e) {
+      DeregisterRunEvents(e.OldItems);
+      RegisterRunEvents(e.Items);
+      UpdateData();
+    }
+    private void Content_UpdateOfRunsInProgressChanged(object sender, EventArgs e) {
+      if (!Content.UpdateOfRunsInProgress) UpdateData();
+    }
+    private void Run_Changed(object sender, EventArgs e) {
+      if (!Content.UpdateOfRunsInProgress) UpdateData();
+    }
+    #endregion
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      this.UpdateData();
+    }
+
+    private void comboBox_SelectedValueChanged(object sender, EventArgs e) {
+      if (comboBox.SelectedItem != null) {
+        var visibleRuns = from run in Content where run.Visible select run;
+        if (comboBox.SelectedIndex == 0) {
+          var selectedFolds = from r in visibleRuns
+                              let foldCollection = (RunCollection)r.Results[crossValidationFoldsResultName]
+                              from run in foldCollection
+                              let name = (r.Name + " " + run.Name)
+                              select new { run, name };
+          matrixView.Content = CalculateVariableImpactMatrix(selectedFolds.Select(x => x.run).ToArray(), selectedFolds.Select(x => x.name).ToArray());
+        } else {
+          var selectedFolds = from r in visibleRuns
+                              let foldCollection = (RunCollection)r.Results[crossValidationFoldsResultName]
+                              let run = foldCollection.ElementAt(comboBox.SelectedIndex - 1)
+                              let name = (r.Name + " " + run.Name)
+                              select new { run, name };
+          matrixView.Content = CalculateVariableImpactMatrix(selectedFolds.Select(x => x.run).ToArray(), selectedFolds.Select(x => x.name).ToArray());
+        }
+      }
+    }
+
+
+    private void UpdateData() {
+      if (InvokeRequired) {
+        Invoke((Action)UpdateData);
+      } else {
+        if (Content != null) {
+          comboBox.Items.Clear();
+          comboBox.Enabled = false;
+          comboBox.Visible = false;
+          foldsLabel.Visible = false;
+          variableImpactsGroupBox.Dock = DockStyle.Fill;
+          var visibleRuns = Content.Where(r => r.Visible).ToArray();
+          if (visibleRuns.Length == 0) {
+            DisplayMessage("Run collection is empty.");
+          } else if (visibleRuns.All(r => r.Parameters.ContainsKey(numberOfFoldsParameterName))) {
+            // check if all runs are comparable (CV or normal runs)
+            CheckAndUpdateCvRuns();
+          } else if (visibleRuns.All(r => !r.Parameters.ContainsKey(numberOfFoldsParameterName))) {
+            CheckAndUpdateNormalRuns();
+          } else {
+            // there is a mix of CV and normal runs => show an error message
+            DisplayMessage("The run collection contains a mixture of normal runs and cross-validation runs. Variable impact calculation does not work in this case.");
+          }
+        }
+      }
+    }
+
+    private void CheckAndUpdateCvRuns() {
+      var visibleRuns = from run in Content where run.Visible select run;
+      var representativeRun = visibleRuns.First();
+      // make sure all runs have the same number of folds
+      int nFolds = ((IntValue)representativeRun.Parameters[numberOfFoldsParameterName]).Value;
+      if (visibleRuns.All(r => ((IntValue)r.Parameters[numberOfFoldsParameterName]).Value == nFolds)) {
+        var allFoldResults = visibleRuns.SelectMany(run => (RunCollection)run.Results[crossValidationFoldsResultName]);
+
+        // make sure each fold contains variable impacts 
+        if (!allFoldResults.All(r => r.Results.ContainsKey(variableImpactResultName))) {
+          DisplayMessage("At least one of the runs does not contain a variable impact result.");
+        } else {
+          // make sure each of the runs has the same input variables
+          var allVariableNames = from run in allFoldResults
+                                 let varImpacts = (DoubleMatrix)run.Results[variableImpactResultName]
+                                 select varImpacts.RowNames;
+          var groupedVariableNames = allVariableNames
+            .SelectMany(x => x)
+            .GroupBy(x => x);
+
+          if (groupedVariableNames.Any(g => g.Count() != allFoldResults.Count())) {
+            DisplayMessage("At least one of the runs has a different input variable set than the rest.");
+          } else {
+            // populate combobox
+            comboBox.Items.Add("Overall");
+            for (int foldIndex = 0; foldIndex < nFolds; foldIndex++) {
+              comboBox.Items.Add("Fold " + foldIndex);
+            }
+            comboBox.SelectedIndex = 0;
+            comboBox.Enabled = true;
+            comboBox.Visible = true;
+            foldsLabel.Visible = true;
+            variableImpactsGroupBox.Controls.Clear();
+            variableImpactsGroupBox.Dock = DockStyle.None;
+            variableImpactsGroupBox.Anchor = AnchorStyles.Left | AnchorStyles.Top | AnchorStyles.Right |
+                                             AnchorStyles.Bottom;
+            variableImpactsGroupBox.Height = this.Height - comboBox.Height - 12;
+            variableImpactsGroupBox.Width = this.Width;
+            matrixView.Dock = DockStyle.Fill;
+            variableImpactsGroupBox.Controls.Add(matrixView);
+          }
+        }
+      } else {
+        DisplayMessage("At least on of the cross-validation runs has a different number of folds than the rest.");
+      }
+    }
+
+    private void CheckAndUpdateNormalRuns() {
+      // make sure all runs contain variable impact results
+      var visibleRuns = from run in Content where run.Visible select run;
+
+      if (!visibleRuns.All(r => r.Results.ContainsKey(variableImpactResultName))) {
+        DisplayMessage("At least one of the runs does not contain a variable impact result.");
+      } else {
+        // make sure each of the runs has the same input variables
+        var allVariableNames = from run in visibleRuns
+                               let varImpacts = (DoubleMatrix)run.Results[variableImpactResultName]
+                               select varImpacts.RowNames;
+        var groupedVariableNames = allVariableNames
+          .SelectMany(x => x)
+          .GroupBy(x => x);
+
+        if (groupedVariableNames.Any(g => g.Count() != visibleRuns.Count())) {
+          DisplayMessage("At least one of the runs has a different input variable set than the rest.");
+        } else {
+          if (!variableImpactsGroupBox.Controls.Contains(matrixView)) {
+            variableImpactsGroupBox.Controls.Clear();
+            matrixView.Dock = DockStyle.Fill;
+            variableImpactsGroupBox.Controls.Add(matrixView);
+          }
+          matrixView.Content = CalculateVariableImpactMatrix(visibleRuns.ToArray(), visibleRuns.Select(r => r.Name).ToArray());
+        }
+      }
+    }
+
+    private DoubleMatrix CalculateVariableImpactMatrix(IRun[] runs, string[] runNames) {
+      DoubleMatrix matrix = null;
+      IEnumerable<DoubleMatrix> allVariableImpacts = (from run in runs
+                                                      select run.Results[variableImpactResultName]).Cast<DoubleMatrix>();
+      IEnumerable<string> variableNames = (from variableImpact in allVariableImpacts
+                                           from variableName in variableImpact.RowNames
+                                           select variableName)
+                                          .Distinct();
+      // filter variableNames: only include names that have at least one non-zero value in a run
+      List<string> variableNamesList = (from variableName in variableNames
+                                        where GetVariableImpacts(variableName, allVariableImpacts).Any(x => !x.IsAlmost(0.0))
+                                        select variableName)
+                                       .ToList();
+
+      List<string> statictics = new List<string> { "Median Rank", "Mean", "StdDev", "pValue" };
+      List<string> columnNames = new List<string>(runNames);
+      columnNames.AddRange(statictics);
+      int numberOfRuns = runs.Length;
+
+      matrix = new DoubleMatrix(variableNamesList.Count, numberOfRuns + statictics.Count);
+      matrix.SortableView = true;
+      matrix.ColumnNames = columnNames;
+
+      // calculate statistics
+      List<List<double>> variableImpactsOverRuns = (from variableName in variableNamesList
+                                                    select GetVariableImpacts(variableName, allVariableImpacts).ToList())
+                                             .ToList();
+      List<List<double>> variableRanks = (from variableName in variableNamesList
+                                          select GetVariableImpactRanks(variableName, allVariableImpacts).ToList())
+                                      .ToList();
+      if (variableImpactsOverRuns.Count() > 0) {
+        // the variable with the worst median impact value is chosen as the reference variable
+        // this is problematic if all variables are relevant, however works often in practice
+        List<double> referenceImpacts = (from impacts in variableImpactsOverRuns
+                                         let avg = impacts.Median()
+                                         orderby avg
+                                         select impacts)
+                                         .First();
+        // for all variables
+        for (int row = 0; row < variableImpactsOverRuns.Count; row++) {
+          // median rank
+          matrix[row, numberOfRuns] = variableRanks[row].Median();
+          // also show mean and std.dev. of relative variable impacts to indicate the relative difference in impacts of variables
+          matrix[row, numberOfRuns + 1] = Math.Round(variableImpactsOverRuns[row].Average(), 3);
+          matrix[row, numberOfRuns + 2] = Math.Round(variableImpactsOverRuns[row].StandardDeviation(), 3);
+
+          double leftTail = 0; double rightTail = 0; double bothTails = 0;
+          // calc differences of impacts for current variable and reference variable
+          double[] z = new double[referenceImpacts.Count];
+          for (int i = 0; i < z.Length; i++) {
+            z[i] = variableImpactsOverRuns[row][i] - referenceImpacts[i];
+          }
+          // wilcoxon signed rank test is used because the impact values of two variables in a single run are not independent
+          alglib.wsr.wilcoxonsignedranktest(z, z.Length, 0, ref bothTails, ref leftTail, ref rightTail);
+          matrix[row, numberOfRuns + 3] = Math.Round(bothTails, 4);
+        }
+      }
+
+      // fill matrix with impacts from runs
+      for (int i = 0; i < runs.Length; i++) {
+        IRun run = runs[i];
+        DoubleMatrix runVariableImpacts = (DoubleMatrix)run.Results[variableImpactResultName];
+        for (int j = 0; j < runVariableImpacts.Rows; j++) {
+          int rowIndex = variableNamesList.FindIndex(s => s == runVariableImpacts.RowNames.ElementAt(j));
+          if (rowIndex > -1) {
+            matrix[rowIndex, i] = Math.Round(runVariableImpacts[j, 0], 3);
+          }
+        }
+      }
+      // sort by median
+      var sortedMatrix = (DoubleMatrix)matrix.Clone();
+      var sortedIndexes = from i in Enumerable.Range(0, sortedMatrix.Rows)
+                          orderby matrix[i, numberOfRuns]
+                          select i;
+
+      int targetIndex = 0;
+      foreach (var sourceIndex in sortedIndexes) {
+        for (int c = 0; c < matrix.Columns; c++)
+          sortedMatrix[targetIndex, c] = matrix[sourceIndex, c];
+        targetIndex++;
+      }
+      sortedMatrix.RowNames = sortedIndexes.Select(i => variableNamesList[i]);
+
+      return sortedMatrix;
+    }
+
+    private IEnumerable<double> GetVariableImpactRanks(string variableName, IEnumerable<DoubleMatrix> allVariableImpacts) {
+      foreach (DoubleMatrix runVariableImpacts in allVariableImpacts) {
+        // certainly not yet very efficient because ranks are computed multiple times for the same run
+        string[] variableNames = runVariableImpacts.RowNames.ToArray();
+        double[] values = (from row in Enumerable.Range(0, runVariableImpacts.Rows)
+                           select runVariableImpacts[row, 0] * -1)
+                          .ToArray();
+        Array.Sort(values, variableNames);
+        // calculate ranks
+        double[] ranks = new double[values.Length];
+        // check for tied ranks
+        int i = 0;
+        while (i < values.Length) {
+          ranks[i] = i + 1;
+          int j = i + 1;
+          while (j < values.Length && values[i].IsAlmost(values[j])) {
+            ranks[j] = ranks[i];
+            j++;
+          }
+          i = j;
+        }
+        int rankIndex = 0;
+        foreach (string rowVariableName in variableNames) {
+          if (rowVariableName == variableName)
+            yield return ranks[rankIndex];
+          rankIndex++;
+        }
+      }
+    }
+
+    private IEnumerable<double> GetVariableImpacts(string variableName, IEnumerable<DoubleMatrix> allVariableImpacts) {
+      foreach (DoubleMatrix runVariableImpacts in allVariableImpacts) {
+        int row = 0;
+        foreach (string rowName in runVariableImpacts.RowNames) {
+          if (rowName == variableName)
+            yield return runVariableImpacts[row, 0];
+          row++;
+        }
+      }
+    }
+
+    private void DisplayMessage(string message) {
+      variableImpactsGroupBox.Controls.Remove(matrixView);
+      var label = new Label { TextAlign = ContentAlignment.MiddleCenter, Text = message, Dock = DockStyle.Fill };
+      variableImpactsGroupBox.Controls.Add(label);
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/ConstantView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/ConstantView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/ConstantView.Designer.cs	(revision 11010)
@@ -0,0 +1,256 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class ConstantView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.weightNuLabel = new System.Windows.Forms.Label();
+      this.minValueTextBox = new System.Windows.Forms.TextBox();
+      this.initializationGroupBox = new System.Windows.Forms.GroupBox();
+      this.weightSigmaLabel = new System.Windows.Forms.Label();
+      this.maxValueTextBox = new System.Windows.Forms.TextBox();
+      this.mutationGroupBox = new System.Windows.Forms.GroupBox();
+      this.multiplicativeChangeLabel = new System.Windows.Forms.Label();
+      this.multiplicativeChangeSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.additiveChangeLabel = new System.Windows.Forms.Label();
+      this.additiveChangeSigmaTextBox = new System.Windows.Forms.TextBox();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.initializationGroupBox.SuspendLayout();
+      this.mutationGroupBox.SuspendLayout();
+      this.SuspendLayout();
+      // 
+      // initialFrequencyLabel
+      // 
+      this.toolTip.SetToolTip(this.initialFrequencyLabel, "Relative frequency of the symbol in randomly created trees");
+      // 
+      // initialFrequencyTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.initialFrequencyTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.initialFrequencyTextBox.Size = new System.Drawing.Size(280, 20);
+      // 
+      // minimumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.minimumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.minimumArityTextBox.Size = new System.Drawing.Size(280, 20);
+      // 
+      // maximumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.maximumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.maximumArityTextBox.Size = new System.Drawing.Size(280, 20);
+      // 
+      // nameTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.nameTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.errorProvider.SetIconPadding(this.nameTextBox, 2);
+      this.nameTextBox.Size = new System.Drawing.Size(280, 20);
+      // 
+      // infoLabel
+      // 
+      this.infoLabel.Location = new System.Drawing.Point(379, 3);
+      // 
+      // weightNuLabel
+      // 
+      this.weightNuLabel.AutoSize = true;
+      this.weightNuLabel.Location = new System.Drawing.Point(6, 22);
+      this.weightNuLabel.Name = "weightNuLabel";
+      this.weightNuLabel.Size = new System.Drawing.Size(56, 13);
+      this.weightNuLabel.TabIndex = 0;
+      this.weightNuLabel.Text = "Min value:";
+      this.toolTip.SetToolTip(this.weightNuLabel, "The minimal value to use for random initialization of constants.");
+      // 
+      // minValueTextBox
+      // 
+      this.minValueTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.errorProvider.SetIconAlignment(this.minValueTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.minValueTextBox.Location = new System.Drawing.Point(92, 19);
+      this.minValueTextBox.Name = "minValueTextBox";
+      this.minValueTextBox.Size = new System.Drawing.Size(300, 20);
+      this.minValueTextBox.TabIndex = 1;
+      this.toolTip.SetToolTip(this.minValueTextBox, "The minimal value to use for random initialization of constants.");
+      this.minValueTextBox.TextChanged += new System.EventHandler(this.minValueTextBox_TextChanged);
+      // 
+      // initializationGroupBox
+      // 
+      this.initializationGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.initializationGroupBox.Controls.Add(this.weightSigmaLabel);
+      this.initializationGroupBox.Controls.Add(this.maxValueTextBox);
+      this.initializationGroupBox.Controls.Add(this.weightNuLabel);
+      this.initializationGroupBox.Controls.Add(this.minValueTextBox);
+      this.initializationGroupBox.Location = new System.Drawing.Point(0, 127);
+      this.initializationGroupBox.Name = "initializationGroupBox";
+      this.initializationGroupBox.Size = new System.Drawing.Size(398, 73);
+      this.initializationGroupBox.TabIndex = 5;
+      this.initializationGroupBox.TabStop = false;
+      this.initializationGroupBox.Text = "Initialization";
+      // 
+      // weightSigmaLabel
+      // 
+      this.weightSigmaLabel.AutoSize = true;
+      this.weightSigmaLabel.Location = new System.Drawing.Point(6, 48);
+      this.weightSigmaLabel.Name = "weightSigmaLabel";
+      this.weightSigmaLabel.Size = new System.Drawing.Size(59, 13);
+      this.weightSigmaLabel.TabIndex = 2;
+      this.weightSigmaLabel.Text = "Max value:";
+      this.toolTip.SetToolTip(this.weightSigmaLabel, "The maximal value to use for random initialization of constants.");
+      // 
+      // maxValueTextBox
+      // 
+      this.maxValueTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.errorProvider.SetIconAlignment(this.maxValueTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.maxValueTextBox.Location = new System.Drawing.Point(92, 45);
+      this.maxValueTextBox.Name = "maxValueTextBox";
+      this.maxValueTextBox.Size = new System.Drawing.Size(300, 20);
+      this.maxValueTextBox.TabIndex = 3;
+      this.toolTip.SetToolTip(this.maxValueTextBox, "The maximal value to use for random initialization of constants.");
+      this.maxValueTextBox.TextChanged += new System.EventHandler(this.maxValueTextBox_TextChanged);
+      // 
+      // mutationGroupBox
+      // 
+      this.mutationGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.mutationGroupBox.Controls.Add(this.multiplicativeChangeLabel);
+      this.mutationGroupBox.Controls.Add(this.multiplicativeChangeSigmaTextBox);
+      this.mutationGroupBox.Controls.Add(this.additiveChangeLabel);
+      this.mutationGroupBox.Controls.Add(this.additiveChangeSigmaTextBox);
+      this.mutationGroupBox.Location = new System.Drawing.Point(0, 206);
+      this.mutationGroupBox.Name = "mutationGroupBox";
+      this.mutationGroupBox.Size = new System.Drawing.Size(398, 73);
+      this.mutationGroupBox.TabIndex = 6;
+      this.mutationGroupBox.TabStop = false;
+      this.mutationGroupBox.Text = "Mutation";
+      // 
+      // multiplicativeChangeLabel
+      // 
+      this.multiplicativeChangeLabel.AutoSize = true;
+      this.multiplicativeChangeLabel.Location = new System.Drawing.Point(6, 48);
+      this.multiplicativeChangeLabel.Name = "multiplicativeChangeLabel";
+      this.multiplicativeChangeLabel.Size = new System.Drawing.Size(146, 13);
+      this.multiplicativeChangeLabel.TabIndex = 2;
+      this.multiplicativeChangeLabel.Text = "Multiplicative change (sigma):";
+      this.toolTip.SetToolTip(this.multiplicativeChangeLabel, "The sigma (std. dev.) parameter for the normal distribution to use to sample the " +
+        "multiplicative change.");
+      // 
+      // multiplicativeChangeSigmaTextBox
+      // 
+      this.multiplicativeChangeSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.errorProvider.SetIconAlignment(this.multiplicativeChangeSigmaTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.multiplicativeChangeSigmaTextBox.Location = new System.Drawing.Point(168, 45);
+      this.multiplicativeChangeSigmaTextBox.Name = "multiplicativeChangeSigmaTextBox";
+      this.multiplicativeChangeSigmaTextBox.Size = new System.Drawing.Size(224, 20);
+      this.multiplicativeChangeSigmaTextBox.TabIndex = 3;
+      this.toolTip.SetToolTip(this.multiplicativeChangeSigmaTextBox, "The sigma (std. dev.) parameter for the normal distribution to use to sample a mu" +
+        "ltiplicative change.");
+      this.multiplicativeChangeSigmaTextBox.TextChanged += new System.EventHandler(this.multiplicativeChangeSigmaTextBox_TextChanged);
+      // 
+      // additiveChangeLabel
+      // 
+      this.additiveChangeLabel.AutoSize = true;
+      this.additiveChangeLabel.Location = new System.Drawing.Point(6, 22);
+      this.additiveChangeLabel.Name = "additiveChangeLabel";
+      this.additiveChangeLabel.Size = new System.Drawing.Size(123, 13);
+      this.additiveChangeLabel.TabIndex = 0;
+      this.additiveChangeLabel.Text = "Additive change (sigma):";
+      this.toolTip.SetToolTip(this.additiveChangeLabel, "The sigma (std. dev.) parameter for the normal distribution to sample the additiv" +
+        "e change.");
+      // 
+      // additiveChangeSigmaTextBox
+      // 
+      this.additiveChangeSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.errorProvider.SetIconAlignment(this.additiveChangeSigmaTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.additiveChangeSigmaTextBox.Location = new System.Drawing.Point(168, 19);
+      this.additiveChangeSigmaTextBox.Name = "additiveChangeSigmaTextBox";
+      this.additiveChangeSigmaTextBox.Size = new System.Drawing.Size(224, 20);
+      this.additiveChangeSigmaTextBox.TabIndex = 1;
+      this.toolTip.SetToolTip(this.additiveChangeSigmaTextBox, "The sigma (std. dev.) parameter for the normal distribution to use to sample an a" +
+        "dditive change.");
+      this.additiveChangeSigmaTextBox.TextChanged += new System.EventHandler(this.additiveChangeSigmaTextBox_TextChanged);
+      // 
+      // ConstantView
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.mutationGroupBox);
+      this.Controls.Add(this.initializationGroupBox);
+      this.Name = "ConstantView";
+      this.Size = new System.Drawing.Size(398, 284);
+      this.Controls.SetChildIndex(this.maximumArityLabel, 0);
+      this.Controls.SetChildIndex(this.maximumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.minimumArityLabel, 0);
+      this.Controls.SetChildIndex(this.minimumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.infoLabel, 0);
+      this.Controls.SetChildIndex(this.initializationGroupBox, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyTextBox, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyLabel, 0);
+      this.Controls.SetChildIndex(this.nameLabel, 0);
+      this.Controls.SetChildIndex(this.nameTextBox, 0);
+      this.Controls.SetChildIndex(this.mutationGroupBox, 0);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.initializationGroupBox.ResumeLayout(false);
+      this.initializationGroupBox.PerformLayout();
+      this.mutationGroupBox.ResumeLayout(false);
+      this.mutationGroupBox.PerformLayout();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.Label weightNuLabel;
+    private System.Windows.Forms.TextBox minValueTextBox;
+    protected System.Windows.Forms.GroupBox initializationGroupBox;
+    private System.Windows.Forms.Label weightSigmaLabel;
+    private System.Windows.Forms.TextBox maxValueTextBox;
+    protected System.Windows.Forms.GroupBox mutationGroupBox;
+    private System.Windows.Forms.Label multiplicativeChangeLabel;
+    private System.Windows.Forms.TextBox multiplicativeChangeSigmaTextBox;
+    private System.Windows.Forms.Label additiveChangeLabel;
+    private System.Windows.Forms.TextBox additiveChangeSigmaTextBox;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/ConstantView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/ConstantView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/ConstantView.cs	(revision 11010)
@@ -0,0 +1,133 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Windows.Forms;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("Constant View")]
+  [Content(typeof(Constant), true)]
+  public partial class ConstantView : SymbolView {
+    public new Constant Content {
+      get { return (Constant)base.Content; }
+      set { base.Content = value; }
+    }
+
+    public ConstantView() {
+      InitializeComponent();
+    }
+
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.Changed += new EventHandler(Content_Changed);
+    }
+
+    protected override void DeregisterContentEvents() {
+      base.DeregisterContentEvents();
+      Content.Changed -= new EventHandler(Content_Changed);
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      UpdateControl();
+    }
+
+    protected override void SetEnabledStateOfControls() {
+      base.SetEnabledStateOfControls();
+      minValueTextBox.Enabled = Content != null;
+      minValueTextBox.ReadOnly = ReadOnly;
+      maxValueTextBox.Enabled = Content != null;
+      maxValueTextBox.ReadOnly = ReadOnly;
+      additiveChangeSigmaTextBox.Enabled = Content != null;
+      additiveChangeSigmaTextBox.ReadOnly = ReadOnly;
+      multiplicativeChangeSigmaTextBox.Enabled = Content != null;
+      multiplicativeChangeSigmaTextBox.ReadOnly = ReadOnly;
+    }
+
+    #region content event handlers
+    private void Content_Changed(object sender, EventArgs e) {
+      UpdateControl();
+    }
+    #endregion
+
+    #region control event handlers
+    private void minValueTextBox_TextChanged(object sender, EventArgs e) {
+      double min;
+      if (double.TryParse(minValueTextBox.Text, out min)) {
+        Content.MinValue = min;
+        errorProvider.SetError(minValueTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(minValueTextBox, "Invalid value");
+      }
+    }
+    private void maxValueTextBox_TextChanged(object sender, EventArgs e) {
+      double max;
+      if (double.TryParse(maxValueTextBox.Text, out max)) {
+        Content.MaxValue = max;
+        errorProvider.SetError(maxValueTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(maxValueTextBox, "Invalid value");
+      }
+    }
+
+    private void additiveChangeSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double sigma;
+      if (double.TryParse(additiveChangeSigmaTextBox.Text, out sigma) && sigma >= 0.0) {
+        Content.ManipulatorSigma = sigma;
+        errorProvider.SetError(additiveChangeSigmaTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(additiveChangeSigmaTextBox, "Invalid value");
+      }
+    }
+
+    private void multiplicativeChangeSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double sigma;
+      if (double.TryParse(multiplicativeChangeSigmaTextBox.Text, out sigma) && sigma >= 0.0) {
+        Content.MultiplicativeManipulatorSigma = sigma;
+        errorProvider.SetError(multiplicativeChangeSigmaTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(multiplicativeChangeSigmaTextBox, "Invalid value");
+      }
+    }
+    #endregion
+
+    #region helpers
+    private void UpdateControl() {
+      if (Content == null) {
+        minValueTextBox.Text = string.Empty;
+        maxValueTextBox.Text = string.Empty;
+        minValueTextBox.Text = string.Empty;
+        multiplicativeChangeSigmaTextBox.Text = string.Empty;
+        additiveChangeSigmaTextBox.Text = string.Empty;
+      } else {
+        minValueTextBox.Text = Content.MinValue.ToString();
+        maxValueTextBox.Text = Content.MaxValue.ToString();
+        additiveChangeSigmaTextBox.Text = Content.ManipulatorSigma.ToString();
+        multiplicativeChangeSigmaTextBox.Text = Content.MultiplicativeManipulatorSigma.ToString();
+      }
+      SetEnabledStateOfControls();
+    }
+    #endregion
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/LaggedVariableView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/LaggedVariableView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/LaggedVariableView.Designer.cs	(revision 11010)
@@ -0,0 +1,226 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class LaggedVariableView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.minTimeOffsetLabel = new System.Windows.Forms.Label();
+      this.maxTimeOffsetLabel = new System.Windows.Forms.Label();
+      this.minTimeOffsetTextBox = new System.Windows.Forms.TextBox();
+      this.maxTimeOffsetTextBox = new System.Windows.Forms.TextBox();
+      this.initializationGroupBox.SuspendLayout();
+      this.mutationGroupBox.SuspendLayout();
+      this.parametersTabPage.SuspendLayout();
+      this.tabControl.SuspendLayout();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.SuspendLayout();
+      // 
+      // weightMuLabel
+      // 
+      this.toolTip.SetToolTip(this.weightMuLabel, "The mu (mean) parameter of the normal distribution to use for initial weights.");
+      // 
+      // weightInitializationMuTextBox
+      // 
+      this.toolTip.SetToolTip(this.weightInitializationMuTextBox, "The mu (mean) parameter of the normal distribution from which to sample the initi" +
+        "al weights.");
+      // 
+      // initializationGroupBox
+      // 
+      this.initializationGroupBox.Location = new System.Drawing.Point(6, 7);
+      this.initializationGroupBox.Size = new System.Drawing.Size(379, 73);
+      // 
+      // weightSigmaLabel
+      // 
+      this.toolTip.SetToolTip(this.weightSigmaLabel, "The sigma parameter for the normal distribution to use for the initial weights.");
+      // 
+      // weightInitializationSigmaTextBox
+      // 
+      this.toolTip.SetToolTip(this.weightInitializationSigmaTextBox, "The sigma parameter for the normal distribution from which to sample the initial " +
+        "weights.");
+      // 
+      // mutationGroupBox
+      // 
+      this.mutationGroupBox.Location = new System.Drawing.Point(6, 86);
+      this.mutationGroupBox.Size = new System.Drawing.Size(379, 73);
+      // 
+      // multiplicativeWeightChangeLabel
+      // 
+      this.toolTip.SetToolTip(this.multiplicativeWeightChangeLabel, "The sigma parameter for the normal distribution to use to sample a multiplicative" +
+        " change in weight.");
+      // 
+      // multiplicativeWeightChangeSigmaTextBox
+      // 
+      this.toolTip.SetToolTip(this.multiplicativeWeightChangeSigmaTextBox, "The sigma (std.dev.) parameter for the normal distribution to sample a multiplica" +
+        "tive change in weight.");
+      // 
+      // additiveWeightChangeLabel
+      // 
+      this.toolTip.SetToolTip(this.additiveWeightChangeLabel, "The sigma (std.dev.) parameter for the normal distribution to sample an additive " +
+        "change in weight.");
+      // 
+      // additiveWeightChangeSigmaTextBox
+      // 
+      this.toolTip.SetToolTip(this.additiveWeightChangeSigmaTextBox, "The sigma (std.dev.) parameter for the normal distribution to sample an additive " +
+        "change in weight.");
+      // 
+      // variableNamesTabPage
+      // 
+      this.variableNamesTabPage.Size = new System.Drawing.Size(400, 149);
+      // 
+      // parametersTabPage
+      // 
+      this.parametersTabPage.Size = new System.Drawing.Size(400, 149);
+      // 
+      // tabControl
+      // 
+      this.tabControl.Location = new System.Drawing.Point(0, 179);
+      this.tabControl.Size = new System.Drawing.Size(408, 175);
+      this.tabControl.TabIndex = 9;
+      // 
+      // initialFrequencyLabel
+      // 
+      this.toolTip.SetToolTip(this.initialFrequencyLabel, "Relative frequency of the symbol in randomly created trees");
+      // 
+      // initialFrequencyTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.initialFrequencyTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      // 
+      // minimumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.minimumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.minimumArityTextBox.Size = new System.Drawing.Size(315, 20);
+      // 
+      // maximumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.maximumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.maximumArityTextBox.Size = new System.Drawing.Size(315, 20);
+      // 
+      // nameTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.nameTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.errorProvider.SetIconPadding(this.nameTextBox, 2);
+      // 
+      // minTimeOffsetLabel
+      // 
+      this.minTimeOffsetLabel.AutoSize = true;
+      this.minTimeOffsetLabel.Location = new System.Drawing.Point(3, 130);
+      this.minTimeOffsetLabel.Name = "minTimeOffsetLabel";
+      this.minTimeOffsetLabel.Size = new System.Drawing.Size(81, 13);
+      this.minTimeOffsetLabel.TabIndex = 5;
+      this.minTimeOffsetLabel.Text = "Min. time offset:";
+      // 
+      // maxTimeOffsetLabel
+      // 
+      this.maxTimeOffsetLabel.AutoSize = true;
+      this.maxTimeOffsetLabel.Location = new System.Drawing.Point(3, 156);
+      this.maxTimeOffsetLabel.Name = "maxTimeOffsetLabel";
+      this.maxTimeOffsetLabel.Size = new System.Drawing.Size(84, 13);
+      this.maxTimeOffsetLabel.TabIndex = 7;
+      this.maxTimeOffsetLabel.Text = "Max. time offset:";
+      // 
+      // minTimeOffsetTextBox
+      // 
+      this.minTimeOffsetTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.minTimeOffsetTextBox.Location = new System.Drawing.Point(93, 127);
+      this.minTimeOffsetTextBox.Name = "minTimeOffsetTextBox";
+      this.minTimeOffsetTextBox.Size = new System.Drawing.Size(315, 20);
+      this.minTimeOffsetTextBox.TabIndex = 6;
+      this.minTimeOffsetTextBox.TextChanged += new System.EventHandler(this.minTimeOffsetTextBox_TextChanged);
+      // 
+      // maxTimeOffsetTextBox
+      // 
+      this.maxTimeOffsetTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.maxTimeOffsetTextBox.Location = new System.Drawing.Point(93, 153);
+      this.maxTimeOffsetTextBox.Name = "maxTimeOffsetTextBox";
+      this.maxTimeOffsetTextBox.Size = new System.Drawing.Size(315, 20);
+      this.maxTimeOffsetTextBox.TabIndex = 8;
+      this.maxTimeOffsetTextBox.TextChanged += new System.EventHandler(this.maxTimeOffsetTextBox_TextChanged);
+      // 
+      // LaggedVariableView
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.minTimeOffsetTextBox);
+      this.Controls.Add(this.maxTimeOffsetLabel);
+      this.Controls.Add(this.minTimeOffsetLabel);
+      this.Controls.Add(this.maxTimeOffsetTextBox);
+      this.Name = "LaggedVariableView";
+      this.Size = new System.Drawing.Size(408, 352);
+      this.Controls.SetChildIndex(this.maxTimeOffsetTextBox, 0);
+      this.Controls.SetChildIndex(this.minTimeOffsetLabel, 0);
+      this.Controls.SetChildIndex(this.maxTimeOffsetLabel, 0);
+      this.Controls.SetChildIndex(this.minTimeOffsetTextBox, 0);
+      this.Controls.SetChildIndex(this.maximumArityLabel, 0);
+      this.Controls.SetChildIndex(this.maximumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.minimumArityLabel, 0);
+      this.Controls.SetChildIndex(this.minimumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.infoLabel, 0);
+      this.Controls.SetChildIndex(this.tabControl, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyTextBox, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyLabel, 0);
+      this.Controls.SetChildIndex(this.nameLabel, 0);
+      this.Controls.SetChildIndex(this.nameTextBox, 0);
+      this.initializationGroupBox.ResumeLayout(false);
+      this.initializationGroupBox.PerformLayout();
+      this.mutationGroupBox.ResumeLayout(false);
+      this.mutationGroupBox.PerformLayout();
+      this.parametersTabPage.ResumeLayout(false);
+      this.tabControl.ResumeLayout(false);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.Label minTimeOffsetLabel;
+    private System.Windows.Forms.Label maxTimeOffsetLabel;
+    private System.Windows.Forms.TextBox minTimeOffsetTextBox;
+    private System.Windows.Forms.TextBox maxTimeOffsetTextBox;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/LaggedVariableView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/LaggedVariableView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/LaggedVariableView.cs	(revision 11010)
@@ -0,0 +1,107 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Windows.Forms;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("LaggedVariable View")]
+  [Content(typeof(LaggedVariable), true)]
+  public partial class LaggedVariableView : VariableView {
+    public new LaggedVariable Content {
+      get { return (LaggedVariable)base.Content; }
+      set { base.Content = value; }
+    }
+
+    public LaggedVariableView() {
+      InitializeComponent();
+    }
+
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.Changed += new EventHandler(Content_Changed);
+    }
+
+    protected override void DeregisterContentEvents() {
+      base.DeregisterContentEvents();
+      Content.Changed -= new EventHandler(Content_Changed);
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      UpdateControl();
+    }
+
+    protected override void SetEnabledStateOfControls() {
+      base.SetEnabledStateOfControls();
+      minTimeOffsetTextBox.Enabled = Content != null;
+      minTimeOffsetTextBox.ReadOnly = ReadOnly;
+      maxTimeOffsetTextBox.Enabled = Content != null;
+      maxTimeOffsetTextBox.ReadOnly = ReadOnly;
+    }
+
+    #region content event handlers
+    private void Content_Changed(object sender, EventArgs e) {
+      UpdateControl();
+    }
+    #endregion
+
+    #region control event handlers
+
+    private void minTimeOffsetTextBox_TextChanged(object sender, EventArgs e) {
+      int timeOffset;
+      if (int.TryParse(minTimeOffsetTextBox.Text, out timeOffset) && timeOffset <= 0) {
+        Content.MinLag = timeOffset;
+        errorProvider.SetError(minTimeOffsetTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(minTimeOffsetTextBox, "Time offset must be negative or zero.");
+      }
+    }
+
+    private void maxTimeOffsetTextBox_TextChanged(object sender, EventArgs e) {
+      int timeOffset;
+      if (int.TryParse(maxTimeOffsetTextBox.Text, out timeOffset) && timeOffset <= 0) {
+        Content.MaxLag = timeOffset;
+        errorProvider.SetError(maxTimeOffsetTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(maxTimeOffsetTextBox, "Time offset must be negative or zero.");
+      }
+    }
+
+    #endregion
+
+    #region helpers
+    private void UpdateControl() {
+      if (Content == null) {
+        minTimeOffsetTextBox.Text = string.Empty;
+        maxTimeOffsetTextBox.Text = string.Empty;
+      } else {
+        minTimeOffsetTextBox.Text = Content.MinLag.ToString();
+        maxTimeOffsetTextBox.Text = Content.MaxLag.ToString();
+      }
+      SetEnabledStateOfControls();
+    }
+    #endregion
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/TimeLagView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/TimeLagView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/TimeLagView.Designer.cs	(revision 11010)
@@ -0,0 +1,159 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class LaggedSymbolView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.minTimeOffsetLabel = new System.Windows.Forms.Label();
+      this.maxTimeOffsetLabel = new System.Windows.Forms.Label();
+      this.minTimeOffsetTextBox = new System.Windows.Forms.TextBox();
+      this.maxTimeOffsetTextBox = new System.Windows.Forms.TextBox();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.SuspendLayout();
+      // 
+      // initialFrequencyLabel
+      // 
+      this.toolTip.SetToolTip(this.initialFrequencyLabel, "Relative frequency of the symbol in randomly created trees");
+      // 
+      // initialFrequencyTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.initialFrequencyTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.initialFrequencyTextBox.Size = new System.Drawing.Size(315, 20);
+      // 
+      // minimumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.minimumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.minimumArityTextBox.Size = new System.Drawing.Size(315, 20);
+      // 
+      // maximumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.maximumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.maximumArityTextBox.Size = new System.Drawing.Size(315, 20);
+      // 
+      // nameTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.nameTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.errorProvider.SetIconPadding(this.nameTextBox, 2);
+      this.nameTextBox.Size = new System.Drawing.Size(290, 20);
+      // 
+      // infoLabel
+      // 
+      this.infoLabel.Location = new System.Drawing.Point(389, 3);
+      // 
+      // minTimeOffsetLabel
+      // 
+      this.minTimeOffsetLabel.AutoSize = true;
+      this.minTimeOffsetLabel.Location = new System.Drawing.Point(3, 130);
+      this.minTimeOffsetLabel.Name = "minTimeOffsetLabel";
+      this.minTimeOffsetLabel.Size = new System.Drawing.Size(81, 13);
+      this.minTimeOffsetLabel.TabIndex = 5;
+      this.minTimeOffsetLabel.Text = "Min. time offset:";
+      // 
+      // maxTimeOffsetLabel
+      // 
+      this.maxTimeOffsetLabel.AutoSize = true;
+      this.maxTimeOffsetLabel.Location = new System.Drawing.Point(3, 156);
+      this.maxTimeOffsetLabel.Name = "maxTimeOffsetLabel";
+      this.maxTimeOffsetLabel.Size = new System.Drawing.Size(84, 13);
+      this.maxTimeOffsetLabel.TabIndex = 7;
+      this.maxTimeOffsetLabel.Text = "Max. time offset:";
+      // 
+      // minTimeOffsetTextBox
+      // 
+      this.minTimeOffsetTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.minTimeOffsetTextBox.Location = new System.Drawing.Point(93, 127);
+      this.minTimeOffsetTextBox.Name = "minTimeOffsetTextBox";
+      this.minTimeOffsetTextBox.Size = new System.Drawing.Size(315, 20);
+      this.minTimeOffsetTextBox.TabIndex = 6;
+      this.minTimeOffsetTextBox.TextChanged += new System.EventHandler(this.minTimeOffsetTextBox_TextChanged);
+      // 
+      // maxTimeOffsetTextBox
+      // 
+      this.maxTimeOffsetTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.maxTimeOffsetTextBox.Location = new System.Drawing.Point(93, 153);
+      this.maxTimeOffsetTextBox.Name = "maxTimeOffsetTextBox";
+      this.maxTimeOffsetTextBox.Size = new System.Drawing.Size(315, 20);
+      this.maxTimeOffsetTextBox.TabIndex = 8;
+      this.maxTimeOffsetTextBox.TextChanged += new System.EventHandler(this.maxTimeOffsetTextBox_TextChanged);
+      // 
+      // LaggedSymbolView
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.maxTimeOffsetTextBox);
+      this.Controls.Add(this.minTimeOffsetTextBox);
+      this.Controls.Add(this.maxTimeOffsetLabel);
+      this.Controls.Add(this.minTimeOffsetLabel);
+      this.Name = "LaggedSymbolView";
+      this.Size = new System.Drawing.Size(408, 179);
+      this.Controls.SetChildIndex(this.maximumArityLabel, 0);
+      this.Controls.SetChildIndex(this.maximumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.minimumArityLabel, 0);
+      this.Controls.SetChildIndex(this.minimumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.infoLabel, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyTextBox, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyLabel, 0);
+      this.Controls.SetChildIndex(this.nameLabel, 0);
+      this.Controls.SetChildIndex(this.nameTextBox, 0);
+      this.Controls.SetChildIndex(this.minTimeOffsetLabel, 0);
+      this.Controls.SetChildIndex(this.maxTimeOffsetLabel, 0);
+      this.Controls.SetChildIndex(this.minTimeOffsetTextBox, 0);
+      this.Controls.SetChildIndex(this.maxTimeOffsetTextBox, 0);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.Label minTimeOffsetLabel;
+    private System.Windows.Forms.Label maxTimeOffsetLabel;
+    private System.Windows.Forms.TextBox minTimeOffsetTextBox;
+    private System.Windows.Forms.TextBox maxTimeOffsetTextBox;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/TimeLagView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/TimeLagView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/TimeLagView.cs	(revision 11010)
@@ -0,0 +1,108 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Windows.Forms;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("LaggedSymbol View")]
+  [Content(typeof(LaggedSymbol), true)]
+  public partial class LaggedSymbolView : SymbolView {
+    public new LaggedSymbol Content {
+      get { return (LaggedSymbol)base.Content; }
+      set { base.Content = value; }
+    }
+
+    public LaggedSymbolView() {
+      InitializeComponent();
+    }
+
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.Changed += new EventHandler(Content_Changed);
+    }
+
+    protected override void DeregisterContentEvents() {
+      base.DeregisterContentEvents();
+      Content.Changed -= new EventHandler(Content_Changed);
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      UpdateControl();
+    }
+
+    protected override void SetEnabledStateOfControls() {
+      base.SetEnabledStateOfControls();
+      minTimeOffsetTextBox.Enabled = Content != null;
+      minTimeOffsetTextBox.ReadOnly = ReadOnly;
+      maxTimeOffsetTextBox.Enabled = Content != null;
+      maxTimeOffsetTextBox.ReadOnly = ReadOnly;
+    }
+
+    #region content event handlers
+    private void Content_Changed(object sender, EventArgs e) {
+      UpdateControl();
+    }
+    #endregion
+
+    #region control event handlers
+
+    private void minTimeOffsetTextBox_TextChanged(object sender, EventArgs e) {
+      int timeOffset;
+      if (int.TryParse(minTimeOffsetTextBox.Text, out timeOffset) && timeOffset <= 0) {
+        Content.MinLag = timeOffset;
+        errorProvider.SetError(minTimeOffsetTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(minTimeOffsetTextBox, "Time offset must be negative or zero.");
+      }
+    }
+
+    private void maxTimeOffsetTextBox_TextChanged(object sender, EventArgs e) {
+      int timeOffset;
+      if (int.TryParse(maxTimeOffsetTextBox.Text, out timeOffset) && timeOffset <= 0) {
+        Content.MaxLag = timeOffset;
+        errorProvider.SetError(maxTimeOffsetTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(maxTimeOffsetTextBox, "Time offset must be negative or zero.");
+      }
+    }
+
+    #endregion
+
+    #region helpers
+    private void UpdateControl() {
+      if (Content == null) {
+        minTimeOffsetTextBox.Text = string.Empty;
+        maxTimeOffsetTextBox.Text = string.Empty;
+      } else {
+        minTimeOffsetTextBox.Text = Content.MinLag.ToString();
+        maxTimeOffsetTextBox.Text = Content.MaxLag.ToString();
+      }
+      SetEnabledStateOfControls();
+    }
+    #endregion
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableConditionView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableConditionView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableConditionView.Designer.cs	(revision 11010)
@@ -0,0 +1,419 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class VariableConditionView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.mutationGroupBox = new System.Windows.Forms.GroupBox();
+      this.slopeChangeSigmaLabel = new System.Windows.Forms.Label();
+      this.slopeChangeSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.slopeChangeMuLabel = new System.Windows.Forms.Label();
+      this.slopeChangeMuTextBox = new System.Windows.Forms.TextBox();
+      this.thresholdChangeSigmaLabel = new System.Windows.Forms.Label();
+      this.thresholdChangeSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.ThresholdChangeMuLabel = new System.Windows.Forms.Label();
+      this.thresholdChangeMuTextBox = new System.Windows.Forms.TextBox();
+      this.tabControl = new System.Windows.Forms.TabControl();
+      this.variableNamesTabPage = new System.Windows.Forms.TabPage();
+      this.parametersTabPage = new System.Windows.Forms.TabPage();
+      this.initializationGroupBox = new System.Windows.Forms.GroupBox();
+      this.slopeInitializationSigmaLabel = new System.Windows.Forms.Label();
+      this.slopeInitializationSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.slopeInitializationMuLabel = new System.Windows.Forms.Label();
+      this.slopeInitializationMuTextBox = new System.Windows.Forms.TextBox();
+      this.thresholdInitializationSigmaLabel = new System.Windows.Forms.Label();
+      this.thresholdInitializationSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.thresholdInitializationMuLabel = new System.Windows.Forms.Label();
+      this.thresholdInitializationMuTextBox = new System.Windows.Forms.TextBox();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.mutationGroupBox.SuspendLayout();
+      this.tabControl.SuspendLayout();
+      this.parametersTabPage.SuspendLayout();
+      this.initializationGroupBox.SuspendLayout();
+      this.SuspendLayout();
+      // 
+      // initialFrequencyLabel
+      // 
+      this.toolTip.SetToolTip(this.initialFrequencyLabel, "Relative frequency of the symbol in randomly created trees");
+      // 
+      // initialFrequencyTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.initialFrequencyTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.initialFrequencyTextBox.Size = new System.Drawing.Size(427, 20);
+      // 
+      // minimumArityLabel
+      // 
+      this.toolTip.SetToolTip(this.minimumArityLabel, "The minimum arity of the symbol");
+      // 
+      // maximumArityLabel
+      // 
+      this.toolTip.SetToolTip(this.maximumArityLabel, "The maximum arity of the symbol");
+      // 
+      // minimumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.minimumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.minimumArityTextBox.Size = new System.Drawing.Size(421, 20);
+      // 
+      // maximumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.maximumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.maximumArityTextBox.Size = new System.Drawing.Size(421, 20);
+      // 
+      // nameTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.nameTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.errorProvider.SetIconPadding(this.nameTextBox, 2);
+      this.nameTextBox.Size = new System.Drawing.Size(397, 20);
+      // 
+      // infoLabel
+      // 
+      this.infoLabel.Location = new System.Drawing.Point(495, 3);
+      // 
+      // mutationGroupBox
+      // 
+      this.mutationGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.mutationGroupBox.Controls.Add(this.slopeChangeSigmaLabel);
+      this.mutationGroupBox.Controls.Add(this.slopeChangeSigmaTextBox);
+      this.mutationGroupBox.Controls.Add(this.slopeChangeMuLabel);
+      this.mutationGroupBox.Controls.Add(this.slopeChangeMuTextBox);
+      this.mutationGroupBox.Controls.Add(this.thresholdChangeSigmaLabel);
+      this.mutationGroupBox.Controls.Add(this.thresholdChangeSigmaTextBox);
+      this.mutationGroupBox.Controls.Add(this.ThresholdChangeMuLabel);
+      this.mutationGroupBox.Controls.Add(this.thresholdChangeMuTextBox);
+      this.mutationGroupBox.Location = new System.Drawing.Point(6, 142);
+      this.mutationGroupBox.Name = "mutationGroupBox";
+      this.mutationGroupBox.Size = new System.Drawing.Size(503, 126);
+      this.mutationGroupBox.TabIndex = 6;
+      this.mutationGroupBox.TabStop = false;
+      this.mutationGroupBox.Text = "Mutation";
+      // 
+      // slopeChangeSigmaLabel
+      // 
+      this.slopeChangeSigmaLabel.AutoSize = true;
+      this.slopeChangeSigmaLabel.Location = new System.Drawing.Point(6, 102);
+      this.slopeChangeSigmaLabel.Name = "slopeChangeSigmaLabel";
+      this.slopeChangeSigmaLabel.Size = new System.Drawing.Size(112, 13);
+      this.slopeChangeSigmaLabel.TabIndex = 6;
+      this.slopeChangeSigmaLabel.Text = "Slope change (sigma):";
+      this.toolTip.SetToolTip(this.slopeChangeSigmaLabel, "The sigma parameter for the normal distribution to use to sample the change in sl" +
+              "ope.");
+      // 
+      // slopeChangeSigmaTextBox
+      // 
+      this.slopeChangeSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.slopeChangeSigmaTextBox.Location = new System.Drawing.Point(149, 99);
+      this.slopeChangeSigmaTextBox.Name = "slopeChangeSigmaTextBox";
+      this.slopeChangeSigmaTextBox.Size = new System.Drawing.Size(345, 20);
+      this.slopeChangeSigmaTextBox.TabIndex = 7;
+      this.toolTip.SetToolTip(this.slopeChangeSigmaTextBox, "The sigma parameter for the normal distribution to use to sample the change in sl" +
+              "ope.");
+      this.slopeChangeSigmaTextBox.TextChanged += new System.EventHandler(this.SlopeChangeSigmaTextBox_TextChanged);
+      // 
+      // slopeChangeMuLabel
+      // 
+      this.slopeChangeMuLabel.AutoSize = true;
+      this.slopeChangeMuLabel.Location = new System.Drawing.Point(6, 76);
+      this.slopeChangeMuLabel.Name = "slopeChangeMuLabel";
+      this.slopeChangeMuLabel.Size = new System.Drawing.Size(99, 13);
+      this.slopeChangeMuLabel.TabIndex = 4;
+      this.slopeChangeMuLabel.Text = "Slope change (mu):";
+      this.toolTip.SetToolTip(this.slopeChangeMuLabel, "The nu (mean) parameter for the normal distribution to sample the change in slope" +
+              ".");
+      // 
+      // slopeChangeMuTextBox
+      // 
+      this.slopeChangeMuTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.slopeChangeMuTextBox.Location = new System.Drawing.Point(149, 73);
+      this.slopeChangeMuTextBox.Name = "slopeChangeMuTextBox";
+      this.slopeChangeMuTextBox.Size = new System.Drawing.Size(345, 20);
+      this.slopeChangeMuTextBox.TabIndex = 5;
+      this.toolTip.SetToolTip(this.slopeChangeMuTextBox, "The mu (mean) parameter for the normal distribution to sample the change in slope" +
+              ".");
+      this.slopeChangeMuTextBox.TextChanged += new System.EventHandler(this.SlopeChangeMuTextBox_TextChanged);
+      // 
+      // thresholdChangeSigmaLabel
+      // 
+      this.thresholdChangeSigmaLabel.AutoSize = true;
+      this.thresholdChangeSigmaLabel.Location = new System.Drawing.Point(6, 44);
+      this.thresholdChangeSigmaLabel.Name = "thresholdChangeSigmaLabel";
+      this.thresholdChangeSigmaLabel.Size = new System.Drawing.Size(132, 13);
+      this.thresholdChangeSigmaLabel.TabIndex = 2;
+      this.thresholdChangeSigmaLabel.Text = "Threshold change (sigma):";
+      this.toolTip.SetToolTip(this.thresholdChangeSigmaLabel, "The sigma parameter for the normal distribution to use to sample the change in th" +
+              "reshold.");
+      // 
+      // thresholdChangeSigmaTextBox
+      // 
+      this.thresholdChangeSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.thresholdChangeSigmaTextBox.Location = new System.Drawing.Point(149, 41);
+      this.thresholdChangeSigmaTextBox.Name = "thresholdChangeSigmaTextBox";
+      this.thresholdChangeSigmaTextBox.Size = new System.Drawing.Size(345, 20);
+      this.thresholdChangeSigmaTextBox.TabIndex = 3;
+      this.toolTip.SetToolTip(this.thresholdChangeSigmaTextBox, "The sigma parameter for the normal distribution to use to sample the change in th" +
+              "reshold.");
+      this.thresholdChangeSigmaTextBox.TextChanged += new System.EventHandler(this.ThresholdChangeSigmaTextBox_TextChanged);
+      // 
+      // ThresholdChangeMuLabel
+      // 
+      this.ThresholdChangeMuLabel.AutoSize = true;
+      this.ThresholdChangeMuLabel.Location = new System.Drawing.Point(6, 18);
+      this.ThresholdChangeMuLabel.Name = "ThresholdChangeMuLabel";
+      this.ThresholdChangeMuLabel.Size = new System.Drawing.Size(119, 13);
+      this.ThresholdChangeMuLabel.TabIndex = 0;
+      this.ThresholdChangeMuLabel.Text = "Threshold change (mu):";
+      this.toolTip.SetToolTip(this.ThresholdChangeMuLabel, "The nu (mean) parameter for the normal distribution to sample the change in thres" +
+              "hold.");
+      // 
+      // thresholdChangeMuTextBox
+      // 
+      this.thresholdChangeMuTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.thresholdChangeMuTextBox.Location = new System.Drawing.Point(149, 15);
+      this.thresholdChangeMuTextBox.Name = "thresholdChangeMuTextBox";
+      this.thresholdChangeMuTextBox.Size = new System.Drawing.Size(345, 20);
+      this.thresholdChangeMuTextBox.TabIndex = 1;
+      this.toolTip.SetToolTip(this.thresholdChangeMuTextBox, "The mu (mean) parameter for the normal distribution to sample the change in thres" +
+              "hold.");
+      this.thresholdChangeMuTextBox.TextChanged += new System.EventHandler(this.ThresholdChangeMuTextBox_TextChanged);
+      // 
+      // tabControl
+      // 
+      this.tabControl.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)
+                  | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.tabControl.Controls.Add(this.variableNamesTabPage);
+      this.tabControl.Controls.Add(this.parametersTabPage);
+      this.tabControl.Location = new System.Drawing.Point(0, 127);
+      this.tabControl.Name = "tabControl";
+      this.tabControl.SelectedIndex = 0;
+      this.tabControl.Size = new System.Drawing.Size(520, 299);
+      this.tabControl.TabIndex = 10;
+      // 
+      // variableNamesTabPage
+      // 
+      this.variableNamesTabPage.Location = new System.Drawing.Point(4, 22);
+      this.variableNamesTabPage.Name = "variableNamesTabPage";
+      this.variableNamesTabPage.Padding = new System.Windows.Forms.Padding(3);
+      this.variableNamesTabPage.Size = new System.Drawing.Size(512, 273);
+      this.variableNamesTabPage.TabIndex = 0;
+      this.variableNamesTabPage.Text = "Variable Names";
+      this.variableNamesTabPage.UseVisualStyleBackColor = true;
+      // 
+      // parametersTabPage
+      // 
+      this.parametersTabPage.Controls.Add(this.initializationGroupBox);
+      this.parametersTabPage.Controls.Add(this.mutationGroupBox);
+      this.parametersTabPage.Location = new System.Drawing.Point(4, 22);
+      this.parametersTabPage.Name = "parametersTabPage";
+      this.parametersTabPage.Padding = new System.Windows.Forms.Padding(3);
+      this.parametersTabPage.Size = new System.Drawing.Size(512, 273);
+      this.parametersTabPage.TabIndex = 1;
+      this.parametersTabPage.Text = "Parameters";
+      this.parametersTabPage.UseVisualStyleBackColor = true;
+      // 
+      // initializationGroupBox
+      // 
+      this.initializationGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.initializationGroupBox.Controls.Add(this.slopeInitializationSigmaLabel);
+      this.initializationGroupBox.Controls.Add(this.slopeInitializationSigmaTextBox);
+      this.initializationGroupBox.Controls.Add(this.slopeInitializationMuLabel);
+      this.initializationGroupBox.Controls.Add(this.slopeInitializationMuTextBox);
+      this.initializationGroupBox.Controls.Add(this.thresholdInitializationSigmaLabel);
+      this.initializationGroupBox.Controls.Add(this.thresholdInitializationSigmaTextBox);
+      this.initializationGroupBox.Controls.Add(this.thresholdInitializationMuLabel);
+      this.initializationGroupBox.Controls.Add(this.thresholdInitializationMuTextBox);
+      this.initializationGroupBox.Location = new System.Drawing.Point(6, 6);
+      this.initializationGroupBox.Name = "initializationGroupBox";
+      this.initializationGroupBox.Size = new System.Drawing.Size(503, 130);
+      this.initializationGroupBox.TabIndex = 6;
+      this.initializationGroupBox.TabStop = false;
+      this.initializationGroupBox.Text = "Initialization";
+      // 
+      // slopeInitializationSigmaLabel
+      // 
+      this.slopeInitializationSigmaLabel.AutoSize = true;
+      this.slopeInitializationSigmaLabel.Location = new System.Drawing.Point(6, 105);
+      this.slopeInitializationSigmaLabel.Name = "slopeInitializationSigmaLabel";
+      this.slopeInitializationSigmaLabel.Size = new System.Drawing.Size(73, 13);
+      this.slopeInitializationSigmaLabel.TabIndex = 6;
+      this.slopeInitializationSigmaLabel.Text = "Slope (sigma):";
+      this.toolTip.SetToolTip(this.slopeInitializationSigmaLabel, "The sigma parameter for the normal distribution to use for the initial slopes.");
+      // 
+      // slopeInitializationSigmaTextBox
+      // 
+      this.slopeInitializationSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.slopeInitializationSigmaTextBox.Location = new System.Drawing.Point(114, 102);
+      this.slopeInitializationSigmaTextBox.Name = "slopeInitializationSigmaTextBox";
+      this.slopeInitializationSigmaTextBox.Size = new System.Drawing.Size(380, 20);
+      this.slopeInitializationSigmaTextBox.TabIndex = 7;
+      this.toolTip.SetToolTip(this.slopeInitializationSigmaTextBox, "The sigma parameter for the normal distribution from which to sample the initial " +
+              "slopes.");
+      this.slopeInitializationSigmaTextBox.TextChanged += new System.EventHandler(this.SlopeInitializationSigmaTextBox_TextChanged);
+      // 
+      // slopeInitializationMuLabel
+      // 
+      this.slopeInitializationMuLabel.AutoSize = true;
+      this.slopeInitializationMuLabel.Location = new System.Drawing.Point(6, 79);
+      this.slopeInitializationMuLabel.Name = "slopeInitializationMuLabel";
+      this.slopeInitializationMuLabel.Size = new System.Drawing.Size(60, 13);
+      this.slopeInitializationMuLabel.TabIndex = 4;
+      this.slopeInitializationMuLabel.Text = "Slope (mu):";
+      this.toolTip.SetToolTip(this.slopeInitializationMuLabel, "The mu (mean) parameter of the normal distribution to use for initial slopes.");
+      // 
+      // slopeInitializationMuTextBox
+      // 
+      this.slopeInitializationMuTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.slopeInitializationMuTextBox.Location = new System.Drawing.Point(114, 76);
+      this.slopeInitializationMuTextBox.Name = "slopeInitializationMuTextBox";
+      this.slopeInitializationMuTextBox.Size = new System.Drawing.Size(380, 20);
+      this.slopeInitializationMuTextBox.TabIndex = 5;
+      this.toolTip.SetToolTip(this.slopeInitializationMuTextBox, "The mu (mean) parameter of the normal distribution from which to sample the initi" +
+              "al slopes.");
+      this.slopeInitializationMuTextBox.TextChanged += new System.EventHandler(this.SlopeInitializationMuTextBox_TextChanged);
+      // 
+      // thresholdInitializationSigmaLabel
+      // 
+      this.thresholdInitializationSigmaLabel.AutoSize = true;
+      this.thresholdInitializationSigmaLabel.Location = new System.Drawing.Point(6, 44);
+      this.thresholdInitializationSigmaLabel.Name = "thresholdInitializationSigmaLabel";
+      this.thresholdInitializationSigmaLabel.Size = new System.Drawing.Size(93, 13);
+      this.thresholdInitializationSigmaLabel.TabIndex = 2;
+      this.thresholdInitializationSigmaLabel.Text = "Threshold (sigma):";
+      this.toolTip.SetToolTip(this.thresholdInitializationSigmaLabel, "The sigma parameter for the normal distribution to use for the initial weights.");
+      // 
+      // thresholdInitializationSigmaTextBox
+      // 
+      this.thresholdInitializationSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.thresholdInitializationSigmaTextBox.Location = new System.Drawing.Point(114, 41);
+      this.thresholdInitializationSigmaTextBox.Name = "thresholdInitializationSigmaTextBox";
+      this.thresholdInitializationSigmaTextBox.Size = new System.Drawing.Size(380, 20);
+      this.thresholdInitializationSigmaTextBox.TabIndex = 3;
+      this.toolTip.SetToolTip(this.thresholdInitializationSigmaTextBox, "The sigma parameter for the normal distribution from which to sample the initial " +
+              "thresholds.");
+      this.thresholdInitializationSigmaTextBox.TextChanged += new System.EventHandler(this.ThresholdInitializationSigmaTextBox_TextChanged);
+      // 
+      // thresholdInitializationMuLabel
+      // 
+      this.thresholdInitializationMuLabel.AutoSize = true;
+      this.thresholdInitializationMuLabel.Location = new System.Drawing.Point(6, 18);
+      this.thresholdInitializationMuLabel.Name = "thresholdInitializationMuLabel";
+      this.thresholdInitializationMuLabel.Size = new System.Drawing.Size(80, 13);
+      this.thresholdInitializationMuLabel.TabIndex = 0;
+      this.thresholdInitializationMuLabel.Text = "Threshold (mu):";
+      this.toolTip.SetToolTip(this.thresholdInitializationMuLabel, "The mu (mean) parameter of the normal distribution to use for initial weights.");
+      // 
+      // thresholdInitializationMuTextBox
+      // 
+      this.thresholdInitializationMuTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left)
+                  | System.Windows.Forms.AnchorStyles.Right)));
+      this.thresholdInitializationMuTextBox.Location = new System.Drawing.Point(114, 15);
+      this.thresholdInitializationMuTextBox.Name = "thresholdInitializationMuTextBox";
+      this.thresholdInitializationMuTextBox.Size = new System.Drawing.Size(380, 20);
+      this.thresholdInitializationMuTextBox.TabIndex = 1;
+      this.toolTip.SetToolTip(this.thresholdInitializationMuTextBox, "The mu (mean) parameter of the normal distribution from which to sample the initi" +
+              "al thresholds.");
+      this.thresholdInitializationMuTextBox.TextChanged += new System.EventHandler(this.ThresholdInitializationMuTextBox_TextChanged);
+      // 
+      // VariableConditionView
+      // 
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.tabControl);
+      this.Name = "VariableConditionView";
+      this.Size = new System.Drawing.Size(520, 426);
+      this.Controls.SetChildIndex(this.maximumArityLabel, 0);
+      this.Controls.SetChildIndex(this.maximumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.minimumArityLabel, 0);
+      this.Controls.SetChildIndex(this.minimumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.infoLabel, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyTextBox, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyLabel, 0);
+      this.Controls.SetChildIndex(this.nameLabel, 0);
+      this.Controls.SetChildIndex(this.nameTextBox, 0);
+      this.Controls.SetChildIndex(this.tabControl, 0);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.mutationGroupBox.ResumeLayout(false);
+      this.mutationGroupBox.PerformLayout();
+      this.tabControl.ResumeLayout(false);
+      this.parametersTabPage.ResumeLayout(false);
+      this.initializationGroupBox.ResumeLayout(false);
+      this.initializationGroupBox.PerformLayout();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    protected System.Windows.Forms.GroupBox mutationGroupBox;
+    private System.Windows.Forms.Label thresholdChangeSigmaLabel;
+    private System.Windows.Forms.TextBox thresholdChangeSigmaTextBox;
+    private System.Windows.Forms.Label ThresholdChangeMuLabel;
+    private System.Windows.Forms.TextBox thresholdChangeMuTextBox;
+    private System.Windows.Forms.Label slopeChangeSigmaLabel;
+    private System.Windows.Forms.TextBox slopeChangeSigmaTextBox;
+    private System.Windows.Forms.Label slopeChangeMuLabel;
+    private System.Windows.Forms.TextBox slopeChangeMuTextBox;
+    protected System.Windows.Forms.TabControl tabControl;
+    protected System.Windows.Forms.TabPage variableNamesTabPage;
+    protected System.Windows.Forms.TabPage parametersTabPage;
+    protected System.Windows.Forms.GroupBox initializationGroupBox;
+    private System.Windows.Forms.Label slopeInitializationSigmaLabel;
+    private System.Windows.Forms.TextBox slopeInitializationSigmaTextBox;
+    private System.Windows.Forms.Label slopeInitializationMuLabel;
+    private System.Windows.Forms.TextBox slopeInitializationMuTextBox;
+    private System.Windows.Forms.Label thresholdInitializationSigmaLabel;
+    private System.Windows.Forms.TextBox thresholdInitializationSigmaTextBox;
+    private System.Windows.Forms.Label thresholdInitializationMuLabel;
+    private System.Windows.Forms.TextBox thresholdInitializationMuTextBox;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableConditionView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableConditionView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableConditionView.cs	(revision 11010)
@@ -0,0 +1,228 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Linq;
+using System.Windows.Forms;
+using HeuristicLab.Collections;
+using HeuristicLab.Core;
+using HeuristicLab.Core.Views;
+using HeuristicLab.Data;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("Variable View")]
+  [Content(typeof(VariableCondition), true)]
+  public partial class VariableConditionView : SymbolView {
+    private readonly CheckedItemCollectionView<StringValue> variableNamesView;
+
+    public new VariableCondition Content {
+      get { return (VariableCondition)base.Content; }
+      set { base.Content = value; }
+    }
+
+    public VariableConditionView() {
+      InitializeComponent();
+      variableNamesView = new CheckedItemCollectionView<StringValue>();
+      variableNamesView.Dock = DockStyle.Fill;
+      variableNamesTabPage.Controls.Add(variableNamesView);
+      variableNamesView.Content = new CheckedItemCollection<StringValue>();
+
+      RegisterVariableNamesViewContentEvents();
+    }
+
+    private void RegisterVariableNamesViewContentEvents() {
+      variableNamesView.Content.ItemsAdded += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.ItemsRemoved += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CheckedItemsChanged += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CollectionReset += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      foreach (var variable in variableNamesView.Content) {
+        variable.ValueChanged += new EventHandler(Variable_ValueChanged);
+      }
+    }
+
+    private void DeregisterVariableNamesViewContentEvents() {
+      variableNamesView.Content.ItemsAdded -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.ItemsRemoved -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CheckedItemsChanged -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CollectionReset -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      foreach (var variable in variableNamesView.Content) {
+        variable.ValueChanged -= new EventHandler(Variable_ValueChanged);
+      }
+    }
+
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.Changed += new EventHandler(Content_Changed);
+    }
+    protected override void DeregisterContentEvents() {
+      base.DeregisterContentEvents();
+      Content.Changed -= new EventHandler(Content_Changed);
+    }
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      UpdateControl();
+    }
+    private void Content_Changed(object sender, EventArgs e) {
+      UpdateControl();
+    }
+
+    protected override void SetEnabledStateOfControls() {
+      base.SetEnabledStateOfControls();
+      thresholdInitializationMuTextBox.Enabled = Content != null;
+      thresholdInitializationMuTextBox.ReadOnly = ReadOnly;
+      thresholdInitializationSigmaTextBox.Enabled = Content != null;
+      thresholdInitializationSigmaTextBox.ReadOnly = ReadOnly;
+      slopeInitializationMuTextBox.Enabled = Content != null;
+      slopeInitializationMuTextBox.ReadOnly = ReadOnly;
+      slopeInitializationSigmaTextBox.Enabled = Content != null;
+      slopeInitializationSigmaTextBox.ReadOnly = ReadOnly;
+
+      thresholdChangeMuTextBox.Enabled = Content != null;
+      thresholdChangeMuTextBox.ReadOnly = ReadOnly;
+      thresholdChangeSigmaTextBox.Enabled = Content != null;
+      thresholdChangeSigmaTextBox.ReadOnly = ReadOnly;
+      slopeChangeMuTextBox.Enabled = Content != null;
+      slopeChangeMuTextBox.ReadOnly = ReadOnly;
+      slopeChangeSigmaTextBox.Enabled = Content != null;
+      slopeChangeSigmaTextBox.ReadOnly = ReadOnly;
+    }
+
+    private void UpdateControl() {
+      if (Content == null) {
+        thresholdInitializationMuTextBox.Text = string.Empty;
+        thresholdInitializationSigmaTextBox.Text = string.Empty;
+        slopeInitializationMuTextBox.Text = string.Empty;
+        slopeInitializationSigmaTextBox.Text = string.Empty;
+        thresholdChangeMuTextBox.Text = string.Empty;
+        thresholdChangeSigmaTextBox.Text = string.Empty;
+        slopeChangeMuTextBox.Text = string.Empty;
+        slopeChangeSigmaTextBox.Text = string.Empty;
+        // temporarily deregister to prevent circular calling of events
+        DeregisterVariableNamesViewContentEvents();
+        variableNamesView.Content.Clear();
+        RegisterVariableNamesViewContentEvents();
+      } else {
+        // temporarily deregister to prevent circular calling of events
+        DeregisterVariableNamesViewContentEvents();
+        variableNamesView.Content.Clear();
+        foreach (var variableName in Content.AllVariableNames) {
+          variableNamesView.Content.Add(new StringValue(variableName), Content.VariableNames.Contains(variableName));
+        }
+        RegisterVariableNamesViewContentEvents();
+
+        thresholdInitializationMuTextBox.Text = Content.ThresholdInitializerMu.ToString();
+        thresholdInitializationSigmaTextBox.Text = Content.ThresholdInitializerSigma.ToString();
+        slopeInitializationMuTextBox.Text = Content.SlopeInitializerMu.ToString();
+        slopeInitializationSigmaTextBox.Text = Content.SlopeInitializerSigma.ToString();
+        thresholdChangeMuTextBox.Text = Content.ThresholdManipulatorMu.ToString();
+        thresholdChangeSigmaTextBox.Text = Content.ThresholdManipulatorSigma.ToString();
+        slopeChangeMuTextBox.Text = Content.SlopeManipulatorMu.ToString();
+        slopeChangeSigmaTextBox.Text = Content.SlopeManipulatorSigma.ToString();
+      }
+      SetEnabledStateOfControls();
+    }
+
+    #region control events
+    private void VariableNames_Changed(object sender, CollectionItemsChangedEventArgs<StringValue> e) {
+      foreach (var newVar in e.Items)
+        newVar.ValueChanged += new EventHandler(Variable_ValueChanged);
+      foreach (var oldVar in e.OldItems)
+        oldVar.ValueChanged -= new EventHandler(Variable_ValueChanged);
+      UpdateContent();
+    }
+
+    private void Variable_ValueChanged(object sender, EventArgs e) {
+      UpdateContent();
+    }
+
+    private void UpdateContent() {
+      if (Content != null) {
+        DeregisterContentEvents();
+        Content.VariableNames = variableNamesView.Content.CheckedItems.Select(x => x.Value).ToList();
+        RegisterContentEvents();
+      }
+    }
+
+    private void ThresholdInitializationMuTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(thresholdInitializationMuTextBox.Text, out value)) {
+        Content.ThresholdInitializerMu = value;
+        errorProvider.SetError(thresholdInitializationMuTextBox, string.Empty);
+      } else errorProvider.SetError(thresholdInitializationMuTextBox, "Invalid value");
+    }
+    private void ThresholdInitializationSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(thresholdInitializationSigmaTextBox.Text, out value)) {
+        Content.ThresholdInitializerSigma = value;
+        errorProvider.SetError(thresholdInitializationSigmaTextBox, string.Empty);
+      } else errorProvider.SetError(thresholdInitializationSigmaTextBox, "Invalid value");
+    }
+    private void SlopeInitializationMuTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(slopeInitializationMuTextBox.Text, out value)) {
+        Content.SlopeInitializerMu = value;
+        errorProvider.SetError(slopeInitializationMuTextBox, string.Empty);
+      } else errorProvider.SetError(slopeInitializationMuTextBox, "Invalid value");
+    }
+    private void SlopeInitializationSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(slopeInitializationSigmaTextBox.Text, out value)) {
+        Content.SlopeInitializerSigma = value;
+        errorProvider.SetError(slopeInitializationSigmaTextBox, string.Empty);
+      } else errorProvider.SetError(slopeInitializationSigmaTextBox, "Invalid value");
+    }
+
+    private void ThresholdChangeMuTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(thresholdChangeMuTextBox.Text, out value)) {
+        Content.ThresholdManipulatorMu = value;
+        errorProvider.SetError(thresholdChangeMuTextBox, string.Empty);
+      } else errorProvider.SetError(thresholdChangeMuTextBox, "Invalid value");
+    }
+
+    private void ThresholdChangeSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(thresholdChangeSigmaTextBox.Text, out value)) {
+        Content.ThresholdManipulatorSigma = value;
+        errorProvider.SetError(thresholdChangeSigmaTextBox, string.Empty);
+      } else errorProvider.SetError(thresholdChangeSigmaTextBox, "Invalid value");
+    }
+    private void SlopeChangeMuTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(slopeChangeMuTextBox.Text, out value)) {
+        Content.SlopeManipulatorMu = value;
+        errorProvider.SetError(slopeChangeMuTextBox, string.Empty);
+      } else errorProvider.SetError(slopeChangeMuTextBox, "Invalid value");
+    }
+
+    private void SlopeChangeSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double value;
+      if (double.TryParse(slopeChangeSigmaTextBox.Text, out value)) {
+        Content.SlopeManipulatorSigma = value;
+        errorProvider.SetError(slopeChangeSigmaTextBox, string.Empty);
+      } else errorProvider.SetError(slopeChangeSigmaTextBox, "Invalid value");
+    }
+    #endregion
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableView.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableView.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableView.Designer.cs	(revision 11010)
@@ -0,0 +1,304 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class VariableView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.weightMuLabel = new System.Windows.Forms.Label();
+      this.weightInitializationMuTextBox = new System.Windows.Forms.TextBox();
+      this.initializationGroupBox = new System.Windows.Forms.GroupBox();
+      this.weightSigmaLabel = new System.Windows.Forms.Label();
+      this.weightInitializationSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.mutationGroupBox = new System.Windows.Forms.GroupBox();
+      this.multiplicativeWeightChangeLabel = new System.Windows.Forms.Label();
+      this.multiplicativeWeightChangeSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.additiveWeightChangeLabel = new System.Windows.Forms.Label();
+      this.additiveWeightChangeSigmaTextBox = new System.Windows.Forms.TextBox();
+      this.tabControl = new System.Windows.Forms.TabControl();
+      this.variableNamesTabPage = new System.Windows.Forms.TabPage();
+      this.parametersTabPage = new System.Windows.Forms.TabPage();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.initializationGroupBox.SuspendLayout();
+      this.mutationGroupBox.SuspendLayout();
+      this.tabControl.SuspendLayout();
+      this.parametersTabPage.SuspendLayout();
+      this.SuspendLayout();
+      // 
+      // initialFrequencyLabel
+      // 
+      this.toolTip.SetToolTip(this.initialFrequencyLabel, "Relative frequency of the symbol in randomly created trees");
+      // 
+      // initialFrequencyTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.initialFrequencyTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.initialFrequencyTextBox.Size = new System.Drawing.Size(311, 20);
+      // 
+      // minimumArityLabel
+      // 
+      this.toolTip.SetToolTip(this.minimumArityLabel, "The minimum arity of the symbol");
+      // 
+      // maximumArityLabel
+      // 
+      this.toolTip.SetToolTip(this.maximumArityLabel, "The maximum arity of the symbol");
+      // 
+      // minimumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.minimumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.minimumArityTextBox.Size = new System.Drawing.Size(311, 20);
+      // 
+      // maximumArityTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.maximumArityTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.maximumArityTextBox.Size = new System.Drawing.Size(311, 20);
+      // 
+      // nameTextBox
+      // 
+      this.errorProvider.SetIconAlignment(this.nameTextBox, System.Windows.Forms.ErrorIconAlignment.MiddleLeft);
+      this.errorProvider.SetIconPadding(this.nameTextBox, 2);
+      this.nameTextBox.Size = new System.Drawing.Size(290, 20);
+      // 
+      // infoLabel
+      // 
+      this.infoLabel.Location = new System.Drawing.Point(389, 3);
+      // 
+      // weightMuLabel
+      // 
+      this.weightMuLabel.AutoSize = true;
+      this.weightMuLabel.Location = new System.Drawing.Point(6, 22);
+      this.weightMuLabel.Name = "weightMuLabel";
+      this.weightMuLabel.Size = new System.Drawing.Size(67, 13);
+      this.weightMuLabel.TabIndex = 0;
+      this.weightMuLabel.Text = "Weight (mu):";
+      this.toolTip.SetToolTip(this.weightMuLabel, "The mu (mean) parameter of the normal distribution to use for initial weights.");
+      // 
+      // weightInitializationMuTextBox
+      // 
+      this.weightInitializationMuTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.weightInitializationMuTextBox.Location = new System.Drawing.Point(92, 19);
+      this.weightInitializationMuTextBox.Name = "weightInitializationMuTextBox";
+      this.weightInitializationMuTextBox.Size = new System.Drawing.Size(290, 20);
+      this.weightInitializationMuTextBox.TabIndex = 1;
+      this.toolTip.SetToolTip(this.weightInitializationMuTextBox, "The mu (mean) parameter of the normal distribution from which to sample the initi" +
+        "al weights.");
+      this.weightInitializationMuTextBox.TextChanged += new System.EventHandler(this.WeightMuTextBox_TextChanged);
+      // 
+      // initializationGroupBox
+      // 
+      this.initializationGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.initializationGroupBox.Controls.Add(this.weightSigmaLabel);
+      this.initializationGroupBox.Controls.Add(this.weightInitializationSigmaTextBox);
+      this.initializationGroupBox.Controls.Add(this.weightMuLabel);
+      this.initializationGroupBox.Controls.Add(this.weightInitializationMuTextBox);
+      this.initializationGroupBox.Location = new System.Drawing.Point(6, 6);
+      this.initializationGroupBox.Name = "initializationGroupBox";
+      this.initializationGroupBox.Size = new System.Drawing.Size(388, 73);
+      this.initializationGroupBox.TabIndex = 0;
+      this.initializationGroupBox.TabStop = false;
+      this.initializationGroupBox.Text = "Initialization";
+      // 
+      // weightSigmaLabel
+      // 
+      this.weightSigmaLabel.AutoSize = true;
+      this.weightSigmaLabel.Location = new System.Drawing.Point(6, 48);
+      this.weightSigmaLabel.Name = "weightSigmaLabel";
+      this.weightSigmaLabel.Size = new System.Drawing.Size(80, 13);
+      this.weightSigmaLabel.TabIndex = 2;
+      this.weightSigmaLabel.Text = "Weight (sigma):";
+      this.toolTip.SetToolTip(this.weightSigmaLabel, "The sigma parameter for the normal distribution to use for the initial weights.");
+      // 
+      // weightInitializationSigmaTextBox
+      // 
+      this.weightInitializationSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.weightInitializationSigmaTextBox.Location = new System.Drawing.Point(92, 45);
+      this.weightInitializationSigmaTextBox.Name = "weightInitializationSigmaTextBox";
+      this.weightInitializationSigmaTextBox.Size = new System.Drawing.Size(290, 20);
+      this.weightInitializationSigmaTextBox.TabIndex = 3;
+      this.toolTip.SetToolTip(this.weightInitializationSigmaTextBox, "The sigma parameter for the normal distribution from which to sample the initial " +
+        "weights.");
+      this.weightInitializationSigmaTextBox.TextChanged += new System.EventHandler(this.WeightSigmaTextBox_TextChanged);
+      // 
+      // mutationGroupBox
+      // 
+      this.mutationGroupBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.mutationGroupBox.Controls.Add(this.multiplicativeWeightChangeLabel);
+      this.mutationGroupBox.Controls.Add(this.multiplicativeWeightChangeSigmaTextBox);
+      this.mutationGroupBox.Controls.Add(this.additiveWeightChangeLabel);
+      this.mutationGroupBox.Controls.Add(this.additiveWeightChangeSigmaTextBox);
+      this.mutationGroupBox.Location = new System.Drawing.Point(6, 85);
+      this.mutationGroupBox.Name = "mutationGroupBox";
+      this.mutationGroupBox.Size = new System.Drawing.Size(391, 73);
+      this.mutationGroupBox.TabIndex = 1;
+      this.mutationGroupBox.TabStop = false;
+      this.mutationGroupBox.Text = "Mutation";
+      // 
+      // multiplicativeWeightChangeLabel
+      // 
+      this.multiplicativeWeightChangeLabel.AutoSize = true;
+      this.multiplicativeWeightChangeLabel.Location = new System.Drawing.Point(6, 48);
+      this.multiplicativeWeightChangeLabel.Name = "multiplicativeWeightChangeLabel";
+      this.multiplicativeWeightChangeLabel.Size = new System.Drawing.Size(180, 13);
+      this.multiplicativeWeightChangeLabel.TabIndex = 2;
+      this.multiplicativeWeightChangeLabel.Text = "Multiplicative weight change (sigma):";
+      this.toolTip.SetToolTip(this.multiplicativeWeightChangeLabel, "The sigma parameter for the normal distribution to use to sample a multiplicative" +
+        " change in weight.");
+      // 
+      // multiplicativeWeightChangeSigmaTextBox
+      // 
+      this.multiplicativeWeightChangeSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.multiplicativeWeightChangeSigmaTextBox.Location = new System.Drawing.Point(201, 45);
+      this.multiplicativeWeightChangeSigmaTextBox.Name = "multiplicativeWeightChangeSigmaTextBox";
+      this.multiplicativeWeightChangeSigmaTextBox.Size = new System.Drawing.Size(184, 20);
+      this.multiplicativeWeightChangeSigmaTextBox.TabIndex = 3;
+      this.toolTip.SetToolTip(this.multiplicativeWeightChangeSigmaTextBox, "The sigma (std.dev.) parameter for the normal distribution to sample a multiplica" +
+        "tive change in weight.");
+      this.multiplicativeWeightChangeSigmaTextBox.TextChanged += new System.EventHandler(this.MultiplicativeWeightChangeSigmaTextBox_TextChanged);
+      // 
+      // additiveWeightChangeLabel
+      // 
+      this.additiveWeightChangeLabel.AutoSize = true;
+      this.additiveWeightChangeLabel.Location = new System.Drawing.Point(6, 22);
+      this.additiveWeightChangeLabel.Name = "additiveWeightChangeLabel";
+      this.additiveWeightChangeLabel.Size = new System.Drawing.Size(157, 13);
+      this.additiveWeightChangeLabel.TabIndex = 0;
+      this.additiveWeightChangeLabel.Text = "Additive weight change (sigma):";
+      this.toolTip.SetToolTip(this.additiveWeightChangeLabel, "The sigma (std.dev.) parameter for the normal distribution to sample an additive " +
+        "change in weight.");
+      // 
+      // additiveWeightChangeSigmaTextBox
+      // 
+      this.additiveWeightChangeSigmaTextBox.Anchor = ((System.Windows.Forms.AnchorStyles)(((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.additiveWeightChangeSigmaTextBox.Location = new System.Drawing.Point(201, 19);
+      this.additiveWeightChangeSigmaTextBox.Name = "additiveWeightChangeSigmaTextBox";
+      this.additiveWeightChangeSigmaTextBox.Size = new System.Drawing.Size(184, 20);
+      this.additiveWeightChangeSigmaTextBox.TabIndex = 1;
+      this.toolTip.SetToolTip(this.additiveWeightChangeSigmaTextBox, "The sigma (std.dev.) parameter for the normal distribution to sample an additive " +
+        "change in weight.");
+      this.additiveWeightChangeSigmaTextBox.TextChanged += new System.EventHandler(this.AdditiveWeightChangeSigmaTextBox_TextChanged);
+      // 
+      // tabControl
+      // 
+      this.tabControl.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
+            | System.Windows.Forms.AnchorStyles.Left) 
+            | System.Windows.Forms.AnchorStyles.Right)));
+      this.tabControl.Controls.Add(this.variableNamesTabPage);
+      this.tabControl.Controls.Add(this.parametersTabPage);
+      this.tabControl.Location = new System.Drawing.Point(0, 127);
+      this.tabControl.Name = "tabControl";
+      this.tabControl.SelectedIndex = 0;
+      this.tabControl.Size = new System.Drawing.Size(408, 190);
+      this.tabControl.TabIndex = 5;
+      // 
+      // variableNamesTabPage
+      // 
+      this.variableNamesTabPage.Location = new System.Drawing.Point(4, 22);
+      this.variableNamesTabPage.Name = "variableNamesTabPage";
+      this.variableNamesTabPage.Padding = new System.Windows.Forms.Padding(3);
+      this.variableNamesTabPage.Size = new System.Drawing.Size(400, 164);
+      this.variableNamesTabPage.TabIndex = 0;
+      this.variableNamesTabPage.Text = "Variable Names";
+      this.variableNamesTabPage.UseVisualStyleBackColor = true;
+      // 
+      // parametersTabPage
+      // 
+      this.parametersTabPage.Controls.Add(this.mutationGroupBox);
+      this.parametersTabPage.Controls.Add(this.initializationGroupBox);
+      this.parametersTabPage.Location = new System.Drawing.Point(4, 22);
+      this.parametersTabPage.Name = "parametersTabPage";
+      this.parametersTabPage.Padding = new System.Windows.Forms.Padding(3);
+      this.parametersTabPage.Size = new System.Drawing.Size(400, 164);
+      this.parametersTabPage.TabIndex = 1;
+      this.parametersTabPage.Text = "Parameters";
+      this.parametersTabPage.UseVisualStyleBackColor = true;
+      // 
+      // VariableView
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.tabControl);
+      this.Name = "VariableView";
+      this.Size = new System.Drawing.Size(408, 317);
+      this.Controls.SetChildIndex(this.maximumArityLabel, 0);
+      this.Controls.SetChildIndex(this.maximumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.minimumArityLabel, 0);
+      this.Controls.SetChildIndex(this.minimumArityTextBox, 0);
+      this.Controls.SetChildIndex(this.infoLabel, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyTextBox, 0);
+      this.Controls.SetChildIndex(this.initialFrequencyLabel, 0);
+      this.Controls.SetChildIndex(this.nameLabel, 0);
+      this.Controls.SetChildIndex(this.nameTextBox, 0);
+      this.Controls.SetChildIndex(this.tabControl, 0);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.initializationGroupBox.ResumeLayout(false);
+      this.initializationGroupBox.PerformLayout();
+      this.mutationGroupBox.ResumeLayout(false);
+      this.mutationGroupBox.PerformLayout();
+      this.tabControl.ResumeLayout(false);
+      this.parametersTabPage.ResumeLayout(false);
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    protected System.Windows.Forms.Label weightMuLabel;
+    protected System.Windows.Forms.TextBox weightInitializationMuTextBox;
+    protected System.Windows.Forms.GroupBox initializationGroupBox;
+    protected System.Windows.Forms.Label weightSigmaLabel;
+    protected System.Windows.Forms.TextBox weightInitializationSigmaTextBox;
+    protected System.Windows.Forms.GroupBox mutationGroupBox;
+    protected System.Windows.Forms.Label multiplicativeWeightChangeLabel;
+    protected System.Windows.Forms.TextBox multiplicativeWeightChangeSigmaTextBox;
+    protected System.Windows.Forms.Label additiveWeightChangeLabel;
+    protected System.Windows.Forms.TextBox additiveWeightChangeSigmaTextBox;
+    protected System.Windows.Forms.TabPage variableNamesTabPage;
+    protected System.Windows.Forms.TabPage parametersTabPage;
+    protected System.Windows.Forms.TabControl tabControl;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/Symbols/VariableView.cs	(revision 11010)
@@ -0,0 +1,201 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Linq;
+using System.Windows.Forms;
+using HeuristicLab.Collections;
+using HeuristicLab.Core;
+using HeuristicLab.Core.Views;
+using HeuristicLab.Data;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("Variable View")]
+  [Content(typeof(Variable), true)]
+  public partial class VariableView : SymbolView {
+    private CheckedItemCollectionView<StringValue> variableNamesView;
+
+    public new Variable Content {
+      get { return (Variable)base.Content; }
+      set { base.Content = value; }
+    }
+
+    public VariableView() {
+      InitializeComponent();
+      variableNamesView = new CheckedItemCollectionView<StringValue>();
+      variableNamesView.Dock = DockStyle.Fill;
+      variableNamesTabPage.Controls.Add(variableNamesView);
+      variableNamesView.Content = new CheckedItemCollection<StringValue>();
+
+      RegisterVariableNamesViewContentEvents();
+    }
+
+    private void RegisterVariableNamesViewContentEvents() {
+      variableNamesView.Content.ItemsAdded += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.ItemsRemoved += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CheckedItemsChanged += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CollectionReset += new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      foreach (var variable in variableNamesView.Content) {
+        variable.ValueChanged += new EventHandler(Variable_ValueChanged);
+      }
+    }
+
+
+    private void DeregisterVariableNamesViewContentEvents() {
+      variableNamesView.Content.ItemsAdded -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.ItemsRemoved -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CheckedItemsChanged -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      variableNamesView.Content.CollectionReset -= new CollectionItemsChangedEventHandler<StringValue>(VariableNames_Changed);
+      foreach (var variable in variableNamesView.Content) {
+        variable.ValueChanged -= new EventHandler(Variable_ValueChanged);
+      }
+    }
+
+
+    protected override void RegisterContentEvents() {
+      base.RegisterContentEvents();
+      Content.Changed += new EventHandler(Content_Changed);
+    }
+
+    protected override void DeregisterContentEvents() {
+      base.DeregisterContentEvents();
+      Content.Changed -= new EventHandler(Content_Changed);
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      UpdateControl();
+    }
+
+    protected override void SetEnabledStateOfControls() {
+      base.SetEnabledStateOfControls();
+      enabledCheckBox.Enabled = Content != null && Content.VariableNames.Any() && !Locked && !ReadOnly;
+      weightInitializationMuTextBox.Enabled = Content != null;
+      weightInitializationMuTextBox.ReadOnly = ReadOnly;
+      weightInitializationSigmaTextBox.Enabled = Content != null;
+      weightInitializationSigmaTextBox.ReadOnly = ReadOnly;
+      additiveWeightChangeSigmaTextBox.Enabled = Content != null;
+      additiveWeightChangeSigmaTextBox.ReadOnly = ReadOnly;
+      multiplicativeWeightChangeSigmaTextBox.Enabled = Content != null;
+      multiplicativeWeightChangeSigmaTextBox.ReadOnly = ReadOnly;
+    }
+
+    #region content event handlers
+    private void Content_Changed(object sender, EventArgs e) {
+      UpdateControl();
+    }
+    #endregion
+
+    #region control event handlers
+    private void VariableNames_Changed(object sender, CollectionItemsChangedEventArgs<StringValue> e) {
+      foreach (var newVar in e.Items)
+        newVar.ValueChanged += new EventHandler(Variable_ValueChanged);
+      foreach (var oldVar in e.OldItems)
+        oldVar.ValueChanged -= new EventHandler(Variable_ValueChanged);
+      UpdateContent();
+    }
+
+    private void Variable_ValueChanged(object sender, EventArgs e) {
+      UpdateContent();
+    }
+
+    private void UpdateContent() {
+      if (Content != null) {
+        Content.Fixed = true;
+        DeregisterContentEvents();
+        Content.VariableNames = variableNamesView.Content.CheckedItems.Select(x => x.Value).ToList();
+        RegisterContentEvents();
+      }
+    }
+
+    private void WeightMuTextBox_TextChanged(object sender, EventArgs e) {
+      double nu;
+      if (double.TryParse(weightInitializationMuTextBox.Text, out nu)) {
+        Content.WeightMu = nu;
+        errorProvider.SetError(weightInitializationMuTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(weightInitializationMuTextBox, "Invalid value");
+      }
+    }
+    private void WeightSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double sigma;
+      if (double.TryParse(weightInitializationSigmaTextBox.Text, out sigma) && sigma >= 0.0) {
+        Content.WeightSigma = sigma;
+        errorProvider.SetError(weightInitializationSigmaTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(weightInitializationSigmaTextBox, "Invalid value");
+      }
+    }
+
+    private void AdditiveWeightChangeSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double sigma;
+      if (double.TryParse(additiveWeightChangeSigmaTextBox.Text, out sigma) && sigma >= 0.0) {
+        Content.WeightManipulatorSigma = sigma;
+        errorProvider.SetError(additiveWeightChangeSigmaTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(additiveWeightChangeSigmaTextBox, "Invalid value");
+      }
+    }
+    private void MultiplicativeWeightChangeSigmaTextBox_TextChanged(object sender, EventArgs e) {
+      double sigma;
+      if (double.TryParse(multiplicativeWeightChangeSigmaTextBox.Text, out sigma) && sigma >= 0.0) {
+        Content.MultiplicativeWeightManipulatorSigma = sigma;
+        errorProvider.SetError(multiplicativeWeightChangeSigmaTextBox, string.Empty);
+      } else {
+        errorProvider.SetError(multiplicativeWeightChangeSigmaTextBox, "Invalid value");
+      }
+    }
+    #endregion
+
+    #region helpers
+    private void UpdateControl() {
+      if (Content == null) {
+        weightInitializationMuTextBox.Text = string.Empty;
+        weightInitializationSigmaTextBox.Text = string.Empty;
+        additiveWeightChangeSigmaTextBox.Text = string.Empty;
+        multiplicativeWeightChangeSigmaTextBox.Text = string.Empty;
+        // temporarily deregister to prevent circular calling of events
+        DeregisterVariableNamesViewContentEvents();
+        variableNamesView.Content.Clear();
+        RegisterVariableNamesViewContentEvents();
+      } else {
+        // temporarily deregister to prevent circular calling of events
+        DeregisterVariableNamesViewContentEvents();
+        variableNamesView.Content.Clear();
+        foreach (var variableName in Content.AllVariableNames) {
+          variableNamesView.Content.Add(new StringValue(variableName), Content.VariableNames.Contains(variableName));
+        }
+        RegisterVariableNamesViewContentEvents();
+
+        weightInitializationMuTextBox.Text = Content.WeightMu.ToString();
+        weightInitializationSigmaTextBox.Text = Content.WeightSigma.ToString();
+        additiveWeightChangeSigmaTextBox.Text = Content.WeightManipulatorSigma.ToString();
+        multiplicativeWeightChangeSigmaTextBox.Text = Content.MultiplicativeWeightManipulatorSigma.ToString();
+      }
+      SetEnabledStateOfControls();
+    }
+    #endregion
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TextualSymbolicDataAnalysisModelView.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TextualSymbolicDataAnalysisModelView.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TextualSymbolicDataAnalysisModelView.cs	(revision 11010)
@@ -0,0 +1,48 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System.Windows.Forms;
+using HeuristicLab.MainForm;
+using HeuristicLab.MainForm.WindowsForms;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  [View("Textual Representation")]
+  [Content(typeof(ISymbolicDataAnalysisModel), false)]
+  public partial class TextualSymbolicDataAnalysisModelView : AsynchronousContentView {
+    public TextualSymbolicDataAnalysisModelView()
+      : base() {
+      InitializeComponent();
+    }
+
+    public new ISymbolicDataAnalysisModel Content {
+      get { return (ISymbolicDataAnalysisModel)base.Content; }
+      set { base.Content = value; }
+    }
+
+    protected override void OnContentChanged() {
+      base.OnContentChanged();
+      if (Content != null)
+        symbolicExpressionTreeView.Content = Content.SymbolicExpressionTree;
+      else
+        symbolicExpressionTreeView.Content = null;
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TextualSymbolicDataAnalysisModelView.designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TextualSymbolicDataAnalysisModelView.designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TextualSymbolicDataAnalysisModelView.designer.cs	(revision 11010)
@@ -0,0 +1,78 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class TextualSymbolicDataAnalysisModelView {
+    /// <summary> 
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary> 
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Component Designer generated code
+
+    /// <summary> 
+    /// Required method for Designer support - do not modify 
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.symbolicExpressionTreeView = new HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views.SymbolicExpressionView();
+      this.SuspendLayout();
+      // 
+      // symbolicExpressionTreeView
+      // 
+      this.symbolicExpressionTreeView.AllowDrop = true;
+      this.symbolicExpressionTreeView.Caption = "Graphical SymbolicExpressionTree View";
+      this.symbolicExpressionTreeView.Content = null;
+      this.symbolicExpressionTreeView.Dock = System.Windows.Forms.DockStyle.Fill;
+      this.symbolicExpressionTreeView.Font = new System.Drawing.Font("Consolas", 8.25F);
+      this.symbolicExpressionTreeView.Location = new System.Drawing.Point(0, 0);
+      this.symbolicExpressionTreeView.Name = "symbolicExpressionTreeView";
+      this.symbolicExpressionTreeView.ReadOnly = false;
+      this.symbolicExpressionTreeView.Size = new System.Drawing.Size(352, 413);
+      this.symbolicExpressionTreeView.TabIndex = 0;
+      // 
+      // TextualSymbolicDataAnalysisModelView
+      // 
+      this.AllowDrop = true;
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit;
+      this.Controls.Add(this.symbolicExpressionTreeView);
+      this.Name = "TextualSymbolicDataAnalysisModelView";
+      this.Size = new System.Drawing.Size(352, 413);
+      this.ResumeLayout(false);
+
+    }
+
+    #endregion
+    private HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Views.SymbolicExpressionView symbolicExpressionTreeView;
+
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeConstantNodeEditDialog.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeConstantNodeEditDialog.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeConstantNodeEditDialog.Designer.cs	(revision 11010)
@@ -0,0 +1,162 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class ConstantNodeEditDialog {
+    /// <summary>
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary>
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing) {
+        if (components != null) components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Windows Form Designer generated code
+
+    /// <summary>
+    /// Required method for Designer support - do not modify
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.components = new System.ComponentModel.Container();
+      this.originalValueLabel = new System.Windows.Forms.Label();
+      this.oldValueTextBox = new System.Windows.Forms.TextBox();
+      this.newValueTextBox = new System.Windows.Forms.TextBox();
+      this.newValueLabel = new System.Windows.Forms.Label();
+      this.errorProvider = new System.Windows.Forms.ErrorProvider(this.components);
+      this.okButton = new System.Windows.Forms.Button();
+      this.cancelButton = new System.Windows.Forms.Button();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.SuspendLayout();
+      // 
+      // originalValueLabel
+      // 
+      this.originalValueLabel.AutoSize = true;
+      this.originalValueLabel.Location = new System.Drawing.Point(12, 9);
+      this.originalValueLabel.Name = "originalValueLabel";
+      this.originalValueLabel.Size = new System.Drawing.Size(72, 13);
+      this.originalValueLabel.TabIndex = 2;
+      this.originalValueLabel.Text = "Original Value";
+      // 
+      // oldValueTextBox
+      // 
+      this.oldValueTextBox.Location = new System.Drawing.Point(123, 6);
+      this.oldValueTextBox.Name = "oldValueTextBox";
+      this.oldValueTextBox.ReadOnly = true;
+      this.oldValueTextBox.Size = new System.Drawing.Size(131, 20);
+      this.oldValueTextBox.TabIndex = 3;
+      // 
+      // newValueTextBox
+      // 
+      this.newValueTextBox.Location = new System.Drawing.Point(123, 42);
+      this.newValueTextBox.Name = "newValueTextBox";
+      this.newValueTextBox.Size = new System.Drawing.Size(131, 20);
+      this.newValueTextBox.TabIndex = 0;
+      this.newValueTextBox.KeyDown += new System.Windows.Forms.KeyEventHandler(this.childControl_KeyDown);
+      this.newValueTextBox.Validating += new System.ComponentModel.CancelEventHandler(this.newValueTextBox_Validating);
+      this.newValueTextBox.Validated += new System.EventHandler(this.newValueTextBox_Validated);
+      // 
+      // newValueLabel
+      // 
+      this.newValueLabel.AutoSize = true;
+      this.newValueLabel.Location = new System.Drawing.Point(12, 45);
+      this.newValueLabel.Name = "newValueLabel";
+      this.newValueLabel.Size = new System.Drawing.Size(59, 13);
+      this.newValueLabel.TabIndex = 5;
+      this.newValueLabel.Text = "New Value";
+      // 
+      // errorProvider
+      // 
+      this.errorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.NeverBlink;
+      this.errorProvider.ContainerControl = this;
+      this.errorProvider.RightToLeft = true;
+      // 
+      // okButton
+      // 
+      this.okButton.DialogResult = System.Windows.Forms.DialogResult.OK;
+      this.okButton.Location = new System.Drawing.Point(15, 79);
+      this.okButton.Name = "okButton";
+      this.okButton.Size = new System.Drawing.Size(75, 23);
+      this.okButton.TabIndex = 8;
+      this.okButton.Text = "OK";
+      this.okButton.UseVisualStyleBackColor = true;
+      this.okButton.Click += new System.EventHandler(this.okButton_Click);
+      // 
+      // cancelButton
+      // 
+      this.cancelButton.CausesValidation = false;
+      this.cancelButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
+      this.cancelButton.Location = new System.Drawing.Point(179, 79);
+      this.cancelButton.Name = "cancelButton";
+      this.cancelButton.Size = new System.Drawing.Size(75, 23);
+      this.cancelButton.TabIndex = 9;
+      this.cancelButton.Text = "Cancel";
+      this.cancelButton.UseVisualStyleBackColor = true;
+      this.cancelButton.Click += new System.EventHandler(this.cancelButton_Click);
+      // 
+      // ConstantNodeEditDialog
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+      this.AutoSize = true;
+      this.CancelButton = this.cancelButton;
+      this.ClientSize = new System.Drawing.Size(269, 116);
+      this.ControlBox = false;
+      this.Controls.Add(this.cancelButton);
+      this.Controls.Add(this.okButton);
+      this.Controls.Add(this.newValueLabel);
+      this.Controls.Add(this.newValueTextBox);
+      this.Controls.Add(this.oldValueTextBox);
+      this.Controls.Add(this.originalValueLabel);
+      this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
+      this.MaximizeBox = false;
+      this.MinimizeBox = false;
+      this.Name = "ConstantNodeEditDialog";
+      this.ShowIcon = false;
+      this.ShowInTaskbar = false;
+      this.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
+      this.Text = "Edit constant value";
+      this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.ConstantNodeEditDialog_KeyDown);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.Label originalValueLabel;
+    private System.Windows.Forms.TextBox oldValueTextBox;
+    private System.Windows.Forms.Label newValueLabel;
+    private System.Windows.Forms.ErrorProvider errorProvider;
+    private System.Windows.Forms.Button cancelButton;
+    private System.Windows.Forms.Button okButton;
+    public System.Windows.Forms.TextBox newValueTextBox;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeConstantNodeEditDialog.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeConstantNodeEditDialog.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeConstantNodeEditDialog.cs	(revision 11010)
@@ -0,0 +1,125 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.ComponentModel;
+using System.Text;
+using System.Windows.Forms;
+using HeuristicLab.Data;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  public partial class ConstantNodeEditDialog : Form {
+    private ConstantTreeNode constantTreeNode;
+    public ConstantTreeNode NewNode {
+      get { return constantTreeNode; }
+      set {
+        if (InvokeRequired)
+          Invoke(new Action<SymbolicExpressionTreeNode>(x => constantTreeNode = (ConstantTreeNode)x), value);
+        else
+          constantTreeNode = value;
+      }
+    }
+
+    public ConstantNodeEditDialog(ISymbolicExpressionTreeNode node) {
+      InitializeComponent();
+      oldValueTextBox.TabStop = false; // cannot receive focus using tab key
+      NewNode = (ConstantTreeNode)node;
+      InitializeFields();
+    }
+
+    private void InitializeFields() {
+      if (NewNode == null)
+        throw new ArgumentException("Node is not a constant.");
+      else {
+        this.Text = "Edit constant";
+        newValueTextBox.Text = oldValueTextBox.Text = Math.Round(constantTreeNode.Value, 4).ToString();
+      }
+    }
+
+    #region text box validation and events
+    private void newValueTextBox_Validating(object sender, CancelEventArgs e) {
+      string errorMessage;
+      if (!ValidateNewValue(newValueTextBox.Text, out errorMessage)) {
+        e.Cancel = true;
+        errorProvider.SetError(newValueTextBox, errorMessage);
+        newValueTextBox.SelectAll();
+      }
+    }
+
+    private void newValueTextBox_Validated(object sender, EventArgs e) {
+      errorProvider.SetError(newValueTextBox, string.Empty);
+    }
+
+    private static bool ValidateNewValue(string value, out string errorMessage) {
+      double val;
+      bool valid = double.TryParse(value, out val);
+      errorMessage = string.Empty;
+      if (!valid) {
+        var sb = new StringBuilder();
+        sb.Append("Invalid Value (Valid Value Format: \"");
+        sb.Append(FormatPatterns.GetDoubleFormatPattern());
+        sb.Append("\")");
+        errorMessage = sb.ToString();
+      }
+      return valid;
+    }
+    #endregion
+
+    // proxy handler passing key strokes to the parent control
+    private void childControl_KeyDown(object sender, KeyEventArgs e) {
+      ConstantNodeEditDialog_KeyDown(sender, e);
+    }
+
+    private void ConstantNodeEditDialog_KeyDown(object sender, KeyEventArgs e) {
+      if ((e.KeyCode == Keys.Enter) || (e.KeyCode == Keys.Return)) {
+        if (!ValidateChildren()) return;
+        OnDialogValidated(this, e); // emit validated effect
+        Close();
+      }
+    }
+
+    public event EventHandler DialogValidated;
+    private void OnDialogValidated(object sender, EventArgs e) {
+      if (constantTreeNode == null) return;
+      var value = double.Parse(newValueTextBox.Text);
+      // we impose an extra validation condition: that the new value is different from the original value
+      if (constantTreeNode.Value.Equals(value)) return;
+
+      constantTreeNode.Value = value;
+      DialogResult = DialogResult.OK;
+      var dialogValidated = DialogValidated;
+      if (dialogValidated != null)
+        dialogValidated(sender, e);
+    }
+
+    private void cancelButton_Click(object sender, EventArgs e) {
+      Close();
+    }
+
+    private void okButton_Click(object sender, EventArgs e) {
+      if (ValidateChildren()) {
+        OnDialogValidated(this, e);
+        Close();
+      }
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeNodeInsertDialog.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeNodeInsertDialog.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeNodeInsertDialog.Designer.cs	(revision 11010)
@@ -0,0 +1,211 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class InsertNodeDialog {
+    /// <summary>
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary>
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing && (components != null)) {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Windows Form Designer generated code
+
+    /// <summary>
+    /// Required method for Designer support - do not modify
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.components = new System.ComponentModel.Container();
+      this.nodeSymbolLabel = new System.Windows.Forms.Label();
+      this.allowedSymbolsCombo = new System.Windows.Forms.ComboBox();
+      this.variableWeightLabel = new System.Windows.Forms.Label();
+      this.variableNameLabel = new System.Windows.Forms.Label();
+      this.variableNamesCombo = new System.Windows.Forms.ComboBox();
+      this.variableWeightTextBox = new System.Windows.Forms.TextBox();
+      this.constantValueTextBox = new System.Windows.Forms.TextBox();
+      this.constantValueLabel = new System.Windows.Forms.Label();
+      this.errorProvider = new System.Windows.Forms.ErrorProvider(this.components);
+      this.okButton = new System.Windows.Forms.Button();
+      this.cancelButton = new System.Windows.Forms.Button();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.SuspendLayout();
+      // 
+      // nodeSymbolLabel
+      // 
+      this.nodeSymbolLabel.AutoSize = true;
+      this.nodeSymbolLabel.Location = new System.Drawing.Point(13, 13);
+      this.nodeSymbolLabel.Name = "nodeSymbolLabel";
+      this.nodeSymbolLabel.Size = new System.Drawing.Size(41, 13);
+      this.nodeSymbolLabel.TabIndex = 0;
+      this.nodeSymbolLabel.Text = "Symbol";
+      // 
+      // allowedSymbolsCombo
+      // 
+      this.allowedSymbolsCombo.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+      this.allowedSymbolsCombo.FormattingEnabled = true;
+      this.allowedSymbolsCombo.Location = new System.Drawing.Point(120, 10);
+      this.allowedSymbolsCombo.Name = "allowedSymbolsCombo";
+      this.allowedSymbolsCombo.Size = new System.Drawing.Size(108, 21);
+      this.allowedSymbolsCombo.TabIndex = 1;
+      this.allowedSymbolsCombo.SelectedIndexChanged += new System.EventHandler(this.allowedSymbolsCombo_SelectedIndexChanged);
+      this.allowedSymbolsCombo.KeyDown += new System.Windows.Forms.KeyEventHandler(this.childControl_KeyDown);
+      // 
+      // variableWeightLabel
+      // 
+      this.variableWeightLabel.AutoSize = true;
+      this.variableWeightLabel.Location = new System.Drawing.Point(13, 44);
+      this.variableWeightLabel.Name = "variableWeightLabel";
+      this.variableWeightLabel.Size = new System.Drawing.Size(41, 13);
+      this.variableWeightLabel.TabIndex = 2;
+      this.variableWeightLabel.Text = "Weight";
+      this.variableWeightLabel.Visible = false;
+      // 
+      // variableNameLabel
+      // 
+      this.variableNameLabel.AutoSize = true;
+      this.variableNameLabel.Location = new System.Drawing.Point(13, 74);
+      this.variableNameLabel.Name = "variableNameLabel";
+      this.variableNameLabel.Size = new System.Drawing.Size(35, 13);
+      this.variableNameLabel.TabIndex = 3;
+      this.variableNameLabel.Text = "Name";
+      this.variableNameLabel.Visible = false;
+      // 
+      // variableNamesCombo
+      // 
+      this.variableNamesCombo.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+      this.variableNamesCombo.FormattingEnabled = true;
+      this.variableNamesCombo.Location = new System.Drawing.Point(120, 71);
+      this.variableNamesCombo.Name = "variableNamesCombo";
+      this.variableNamesCombo.Size = new System.Drawing.Size(108, 21);
+      this.variableNamesCombo.TabIndex = 5;
+      this.variableNamesCombo.Visible = false;
+      // 
+      // variableWeightTextBox
+      // 
+      this.variableWeightTextBox.Location = new System.Drawing.Point(120, 41);
+      this.variableWeightTextBox.Name = "variableWeightTextBox";
+      this.variableWeightTextBox.Size = new System.Drawing.Size(108, 20);
+      this.variableWeightTextBox.TabIndex = 6;
+      this.variableWeightTextBox.Text = "0.0";
+      this.variableWeightTextBox.Visible = false;
+      this.variableWeightTextBox.Validating += new System.ComponentModel.CancelEventHandler(this.variableWeightTextBox_Validating);
+      // 
+      // constantValueTextBox
+      // 
+      this.constantValueTextBox.Location = new System.Drawing.Point(120, 41);
+      this.constantValueTextBox.Name = "constantValueTextBox";
+      this.constantValueTextBox.Size = new System.Drawing.Size(108, 20);
+      this.constantValueTextBox.TabIndex = 7;
+      this.constantValueTextBox.Text = "0.0";
+      this.constantValueTextBox.Visible = false;
+      this.constantValueTextBox.Validating += new System.ComponentModel.CancelEventHandler(this.constantValueTextBox_Validating);
+      // 
+      // constantValueLabel
+      // 
+      this.constantValueLabel.AutoSize = true;
+      this.constantValueLabel.Location = new System.Drawing.Point(13, 44);
+      this.constantValueLabel.Name = "constantValueLabel";
+      this.constantValueLabel.Size = new System.Drawing.Size(34, 13);
+      this.constantValueLabel.TabIndex = 8;
+      this.constantValueLabel.Text = "Value";
+      this.constantValueLabel.Visible = false;
+      // 
+      // errorProvider
+      // 
+      this.errorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.NeverBlink;
+      this.errorProvider.ContainerControl = this;
+      this.errorProvider.RightToLeft = true;
+      // 
+      // okButton
+      // 
+      this.okButton.DialogResult = System.Windows.Forms.DialogResult.OK;
+      this.okButton.Location = new System.Drawing.Point(12, 112);
+      this.okButton.Name = "okButton";
+      this.okButton.Size = new System.Drawing.Size(75, 23);
+      this.okButton.TabIndex = 9;
+      this.okButton.Text = "OK";
+      this.okButton.UseVisualStyleBackColor = true;
+      this.okButton.Click += new System.EventHandler(this.okButton_Click);
+      // 
+      // cancelButton
+      // 
+      this.cancelButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
+      this.cancelButton.Location = new System.Drawing.Point(153, 112);
+      this.cancelButton.Name = "cancelButton";
+      this.cancelButton.Size = new System.Drawing.Size(75, 23);
+      this.cancelButton.TabIndex = 10;
+      this.cancelButton.Text = "Cancel";
+      this.cancelButton.UseVisualStyleBackColor = true;
+      this.cancelButton.Click += new System.EventHandler(this.cancelButton_Click);
+      // 
+      // InsertNodeDialog
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+      this.CancelButton = this.cancelButton;
+      this.ClientSize = new System.Drawing.Size(240, 147);
+      this.ControlBox = false;
+      this.Controls.Add(this.cancelButton);
+      this.Controls.Add(this.okButton);
+      this.Controls.Add(this.constantValueLabel);
+      this.Controls.Add(this.constantValueTextBox);
+      this.Controls.Add(this.variableWeightTextBox);
+      this.Controls.Add(this.variableNamesCombo);
+      this.Controls.Add(this.variableNameLabel);
+      this.Controls.Add(this.variableWeightLabel);
+      this.Controls.Add(this.allowedSymbolsCombo);
+      this.Controls.Add(this.nodeSymbolLabel);
+      this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
+      this.Name = "InsertNodeDialog";
+      this.Text = "SymbolicExpressionTreeNodeInsertDialog";
+      this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.insertNodeDialog_KeyDown);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.Label nodeSymbolLabel;
+    private System.Windows.Forms.ComboBox allowedSymbolsCombo;
+    private System.Windows.Forms.Label variableWeightLabel;
+    private System.Windows.Forms.Label variableNameLabel;
+    private System.Windows.Forms.Label constantValueLabel;
+    private System.Windows.Forms.ErrorProvider errorProvider;
+    internal System.Windows.Forms.TextBox constantValueTextBox;
+    internal System.Windows.Forms.TextBox variableWeightTextBox;
+    internal System.Windows.Forms.ComboBox variableNamesCombo;
+    private System.Windows.Forms.Button cancelButton;
+    private System.Windows.Forms.Button okButton;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeNodeInsertDialog.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeNodeInsertDialog.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeNodeInsertDialog.cs	(revision 11010)
@@ -0,0 +1,141 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Text;
+using System.Windows.Forms;
+using HeuristicLab.Data;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  public partial class InsertNodeDialog : Form {
+    public InsertNodeDialog() {
+      InitializeComponent();
+    }
+
+    public void SetAllowedSymbols(IEnumerable<ISymbol> symbols) {
+      allowedSymbolsCombo.Items.Clear();
+      foreach (var s in symbols) allowedSymbolsCombo.Items.Add(s);
+      allowedSymbolsCombo.SelectedIndex = 0;
+    }
+
+    public ISymbol SelectedSymbol() {
+      return (ISymbol)allowedSymbolsCombo.SelectedItem;
+    }
+
+    private void allowedSymbolsCombo_SelectedIndexChanged(object sender, EventArgs e) {
+      var combo = (ComboBox)sender;
+      var symbol = combo.Items[combo.SelectedIndex];
+      if (symbol is Constant) {
+        // add controls to the dialog for changing the constant value
+        variableNameLabel.Visible = false;
+        variableNamesCombo.Visible = false;
+        variableWeightLabel.Visible = false;
+        variableWeightTextBox.Visible = false;
+        constantValueLabel.Visible = true;
+        constantValueTextBox.Visible = true;
+      } else if (symbol is Variable) {
+        var variable = (Variable)symbol;
+        foreach (var name in variable.VariableNames) variableNamesCombo.Items.Add(name);
+        variableNamesCombo.SelectedIndex = 0;
+        variableNameLabel.Visible = true;
+        variableNamesCombo.Visible = true;
+        variableWeightLabel.Visible = true;
+        variableWeightTextBox.Visible = true;
+        constantValueLabel.Visible = false;
+        constantValueTextBox.Visible = false;
+        // add controls to the dialog for changing the variable name or weight
+      } else {
+        variableNameLabel.Visible = false;
+        variableNamesCombo.Visible = false;
+        variableWeightLabel.Visible = false;
+        variableWeightTextBox.Visible = false;
+        constantValueLabel.Visible = false;
+        constantValueTextBox.Visible = false;
+      }
+    }
+
+    // validation
+    private void variableWeightTextBox_Validating(object sender, CancelEventArgs e) {
+      string errorMessage;
+      if (ValidateDoubleValue(variableWeightTextBox.Text, out errorMessage)) return;
+      e.Cancel = true;
+      errorProvider.SetError(variableWeightTextBox, errorMessage);
+      variableWeightTextBox.SelectAll();
+    }
+
+    private void constantValueTextBox_Validating(object sender, CancelEventArgs e) {
+      string errorMessage;
+      if (ValidateDoubleValue(constantValueTextBox.Text, out errorMessage)) return;
+      e.Cancel = true;
+      errorProvider.SetError(constantValueTextBox, errorMessage);
+      constantValueTextBox.SelectAll();
+    }
+
+    private static bool ValidateDoubleValue(string value, out string errorMessage) {
+      double val;
+      bool valid = double.TryParse(value, out val);
+      errorMessage = string.Empty;
+      if (!valid) {
+        var sb = new StringBuilder();
+        sb.Append("Invalid Value (Valid Value Format: \"");
+        sb.Append(FormatPatterns.GetDoubleFormatPattern());
+        sb.Append("\")");
+        errorMessage = sb.ToString();
+      }
+      return valid;
+    }
+
+    public event EventHandler DialogValidated;
+    private void OnDialogValidated(object sender, EventArgs e) {
+      DialogResult = DialogResult.OK;
+      var dialogValidated = DialogValidated;
+      if (dialogValidated != null)
+        dialogValidated(sender, e);
+    }
+
+    private void childControl_KeyDown(object sender, KeyEventArgs e) {
+      insertNodeDialog_KeyDown(sender, e);
+    }
+
+    private void insertNodeDialog_KeyDown(object sender, KeyEventArgs e) {
+      if (e.KeyCode == Keys.Enter || e.KeyCode == Keys.Return) {
+        if (ValidateChildren()) {
+          OnDialogValidated(this, e);
+          Close();
+        }
+      }
+    }
+
+    private void okButton_Click(object sender, EventArgs e) {
+      if (ValidateChildren()) {
+        OnDialogValidated(this, e);
+        Close();
+      }
+    }
+
+    private void cancelButton_Click(object sender, EventArgs e) {
+      Close();
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeVariableNodeEditDialog.Designer.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeVariableNodeEditDialog.Designer.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeVariableNodeEditDialog.Designer.cs	(revision 11010)
@@ -0,0 +1,191 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  partial class VariableNodeEditDialog {
+    /// <summary>
+    /// Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary>
+    /// Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing) {
+      if (disposing) {
+        if (components != null) components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Windows Form Designer generated code
+
+    /// <summary>
+    /// Required method for Designer support - do not modify
+    /// the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent() {
+      this.components = new System.ComponentModel.Container();
+      this.originalValueLabel = new System.Windows.Forms.Label();
+      this.oldValueTextBox = new System.Windows.Forms.TextBox();
+      this.newValueTextBox = new System.Windows.Forms.TextBox();
+      this.newValueLabel = new System.Windows.Forms.Label();
+      this.errorProvider = new System.Windows.Forms.ErrorProvider(this.components);
+      this.variableNameLabel = new System.Windows.Forms.Label();
+      this.variableNamesCombo = new System.Windows.Forms.ComboBox();
+      this.okButton = new System.Windows.Forms.Button();
+      this.cancelButton = new System.Windows.Forms.Button();
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).BeginInit();
+      this.SuspendLayout();
+      // 
+      // originalValueLabel
+      // 
+      this.originalValueLabel.AutoSize = true;
+      this.originalValueLabel.Location = new System.Drawing.Point(12, 48);
+      this.originalValueLabel.Name = "originalValueLabel";
+      this.originalValueLabel.Size = new System.Drawing.Size(72, 13);
+      this.originalValueLabel.TabIndex = 2;
+      this.originalValueLabel.Text = "Original Value";
+      // 
+      // oldValueTextBox
+      // 
+      this.oldValueTextBox.Location = new System.Drawing.Point(123, 45);
+      this.oldValueTextBox.Name = "oldValueTextBox";
+      this.oldValueTextBox.ReadOnly = true;
+      this.oldValueTextBox.Size = new System.Drawing.Size(131, 20);
+      this.oldValueTextBox.TabIndex = 3;
+      // 
+      // newValueTextBox
+      // 
+      this.newValueTextBox.Location = new System.Drawing.Point(123, 82);
+      this.newValueTextBox.Name = "newValueTextBox";
+      this.newValueTextBox.Size = new System.Drawing.Size(131, 20);
+      this.newValueTextBox.TabIndex = 0;
+      this.newValueTextBox.KeyDown += new System.Windows.Forms.KeyEventHandler(this.childControl_KeyDown);
+      this.newValueTextBox.Validating += new System.ComponentModel.CancelEventHandler(this.newValueTextBox_Validating);
+      this.newValueTextBox.Validated += new System.EventHandler(this.newValueTextBox_Validated);
+      // 
+      // newValueLabel
+      // 
+      this.newValueLabel.AutoSize = true;
+      this.newValueLabel.Location = new System.Drawing.Point(12, 85);
+      this.newValueLabel.Name = "newValueLabel";
+      this.newValueLabel.Size = new System.Drawing.Size(59, 13);
+      this.newValueLabel.TabIndex = 5;
+      this.newValueLabel.Text = "New Value";
+      // 
+      // errorProvider
+      // 
+      this.errorProvider.BlinkStyle = System.Windows.Forms.ErrorBlinkStyle.NeverBlink;
+      this.errorProvider.ContainerControl = this;
+      this.errorProvider.RightToLeft = true;
+      // 
+      // variableNameLabel
+      // 
+      this.variableNameLabel.AutoSize = true;
+      this.variableNameLabel.Location = new System.Drawing.Point(12, 12);
+      this.variableNameLabel.Name = "variableNameLabel";
+      this.variableNameLabel.Size = new System.Drawing.Size(76, 13);
+      this.variableNameLabel.TabIndex = 6;
+      this.variableNameLabel.Text = "Variable Name";
+      this.variableNameLabel.Visible = false;
+      // 
+      // variableNamesCombo
+      // 
+      this.variableNamesCombo.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+      this.variableNamesCombo.FormattingEnabled = true;
+      this.variableNamesCombo.Location = new System.Drawing.Point(123, 9);
+      this.variableNamesCombo.Name = "variableNamesCombo";
+      this.variableNamesCombo.Size = new System.Drawing.Size(131, 21);
+      this.variableNamesCombo.TabIndex = 7;
+      this.variableNamesCombo.Visible = false;
+      this.variableNamesCombo.KeyDown += new System.Windows.Forms.KeyEventHandler(this.childControl_KeyDown);
+      this.variableNamesCombo.Validating += new System.ComponentModel.CancelEventHandler(this.variableNamesCombo_Validating);
+      this.variableNamesCombo.Validated += new System.EventHandler(this.variableNamesCombo_Validated);
+      // 
+      // okButton
+      // 
+      this.okButton.DialogResult = System.Windows.Forms.DialogResult.OK;
+      this.okButton.Location = new System.Drawing.Point(15, 119);
+      this.okButton.Name = "okButton";
+      this.okButton.Size = new System.Drawing.Size(75, 23);
+      this.okButton.TabIndex = 8;
+      this.okButton.Text = "OK";
+      this.okButton.UseVisualStyleBackColor = true;
+      this.okButton.Click += new System.EventHandler(this.okButton_Click);
+      // 
+      // cancelButton
+      // 
+      this.cancelButton.CausesValidation = false;
+      this.cancelButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
+      this.cancelButton.Location = new System.Drawing.Point(179, 119);
+      this.cancelButton.Name = "cancelButton";
+      this.cancelButton.Size = new System.Drawing.Size(75, 23);
+      this.cancelButton.TabIndex = 9;
+      this.cancelButton.Text = "Cancel";
+      this.cancelButton.UseVisualStyleBackColor = true;
+      this.cancelButton.Click += new System.EventHandler(this.cancelButton_Click);
+      // 
+      // VariableNodeEditDialog
+      // 
+      this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+      this.AutoSize = true;
+      this.CancelButton = this.cancelButton;
+      this.ClientSize = new System.Drawing.Size(269, 154);
+      this.ControlBox = false;
+      this.Controls.Add(this.cancelButton);
+      this.Controls.Add(this.okButton);
+      this.Controls.Add(this.variableNamesCombo);
+      this.Controls.Add(this.variableNameLabel);
+      this.Controls.Add(this.newValueLabel);
+      this.Controls.Add(this.newValueTextBox);
+      this.Controls.Add(this.oldValueTextBox);
+      this.Controls.Add(this.originalValueLabel);
+      this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;
+      this.MaximizeBox = false;
+      this.MinimizeBox = false;
+      this.Name = "VariableNodeEditDialog";
+      this.ShowIcon = false;
+      this.ShowInTaskbar = false;
+      this.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent;
+      this.Text = "Change Value or Weight";
+      this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.ValueChangeDialog_KeyDown);
+      ((System.ComponentModel.ISupportInitialize)(this.errorProvider)).EndInit();
+      this.ResumeLayout(false);
+      this.PerformLayout();
+
+    }
+
+    #endregion
+
+    private System.Windows.Forms.Label originalValueLabel;
+    private System.Windows.Forms.TextBox oldValueTextBox;
+    private System.Windows.Forms.Label newValueLabel;
+    private System.Windows.Forms.ErrorProvider errorProvider;
+    private System.Windows.Forms.Label variableNameLabel;
+    private System.Windows.Forms.Button cancelButton;
+    private System.Windows.Forms.Button okButton;
+    public System.Windows.Forms.TextBox newValueTextBox;
+    public System.Windows.Forms.ComboBox variableNamesCombo;
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeVariableNodeEditDialog.cs
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeVariableNodeEditDialog.cs	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/TreeEditDialogs/SymbolicExpressionTreeVariableNodeEditDialog.cs	(revision 11010)
@@ -0,0 +1,143 @@
+#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ *
+ * This file is part of HeuristicLab.
+ *
+ * HeuristicLab is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * HeuristicLab is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
+ */
+#endregion
+
+using System;
+using System.ComponentModel;
+using System.Text;
+using System.Windows.Forms;
+using HeuristicLab.Data;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
+  public partial class VariableNodeEditDialog : Form {
+    private VariableTreeNode variableTreeNode;
+    public VariableTreeNode NewNode {
+      get { return variableTreeNode; }
+      set {
+        if (InvokeRequired)
+          Invoke(new Action<SymbolicExpressionTreeNode>(x => variableTreeNode = (VariableTreeNode)x), value);
+        else
+          variableTreeNode = value;
+      }
+    }
+
+    public VariableNodeEditDialog(ISymbolicExpressionTreeNode node) {
+      InitializeComponent();
+      oldValueTextBox.TabStop = false; // cannot receive focus using tab key
+
+      NewNode = (VariableTreeNode)node; // will throw an invalid cast exception if node is not of the correct type
+      InitializeFields();
+    }
+
+    private void InitializeFields() {
+      if (NewNode == null)
+        throw new ArgumentException("Node is not a constant.");
+      else {
+        this.Text = "Edit variable";
+        newValueTextBox.Text = oldValueTextBox.Text = Math.Round(variableTreeNode.Weight, 4).ToString();
+        // add a dropbox containing all the available variable names
+        variableNameLabel.Visible = true;
+        variableNamesCombo.Visible = true;
+        foreach (var name in variableTreeNode.Symbol.VariableNames) variableNamesCombo.Items.Add(name);
+        variableNamesCombo.SelectedIndex = variableNamesCombo.Items.IndexOf(variableTreeNode.VariableName);
+      }
+    }
+
+    #region text box validation and events
+    private void newValueTextBox_Validating(object sender, CancelEventArgs e) {
+      string errorMessage;
+      if (!ValidateNewValue(newValueTextBox.Text, out errorMessage)) {
+        e.Cancel = true;
+        errorProvider.SetError(newValueTextBox, errorMessage);
+        newValueTextBox.SelectAll();
+      }
+    }
+
+    private void newValueTextBox_Validated(object sender, EventArgs e) {
+      errorProvider.SetError(newValueTextBox, string.Empty);
+    }
+
+    private static bool ValidateNewValue(string value, out string errorMessage) {
+      double val;
+      bool valid = double.TryParse(value, out val);
+      errorMessage = string.Empty;
+      if (!valid) {
+        var sb = new StringBuilder();
+        sb.Append("Invalid Value (Valid Value Format: \"");
+        sb.Append(FormatPatterns.GetDoubleFormatPattern());
+        sb.Append("\")");
+        errorMessage = sb.ToString();
+      }
+      return valid;
+    }
+    #endregion
+
+    #region combo box validation and events
+    private void variableNamesCombo_Validating(object sender, CancelEventArgs e) {
+      if (variableNamesCombo.Items.Contains(variableNamesCombo.SelectedItem)) return;
+      e.Cancel = true;
+      errorProvider.SetError(variableNamesCombo, "Invalid variable name");
+      variableNamesCombo.SelectAll();
+    }
+
+    private void variableNamesCombo_Validated(object sender, EventArgs e) {
+      errorProvider.SetError(variableNamesCombo, String.Empty);
+    }
+    #endregion
+    // proxy handler passing key strokes to the parent control
+    private void childControl_KeyDown(object sender, KeyEventArgs e) {
+      ValueChangeDialog_KeyDown(sender, e);
+    }
+
+    private void ValueChangeDialog_KeyDown(object sender, KeyEventArgs e) {
+      if ((e.KeyCode == Keys.Enter) || (e.KeyCode == Keys.Return)) {
+        if (!ValidateChildren()) return;
+        OnDialogValidated(this, e); // emit validated effect
+        Close();
+      }
+    }
+
+    public event EventHandler DialogValidated;
+    private void OnDialogValidated(object sender, EventArgs e) {
+      double weight = double.Parse(newValueTextBox.Text);
+      var variableName = (string)variableNamesCombo.SelectedItem;
+      // we impose an extra validation condition: that the weight/value be different than the original ones
+      if (variableTreeNode.Weight.Equals(weight) && variableTreeNode.VariableName.Equals(variableName)) return;
+      variableTreeNode.Weight = weight;
+      variableTreeNode.VariableName = variableName;
+      DialogResult = DialogResult.OK;
+      var dialogValidated = DialogValidated;
+      if (dialogValidated != null)
+        dialogValidated(sender, e);
+    }
+
+    private void cancelButton_Click(object sender, EventArgs e) {
+      Close();
+    }
+
+    private void okButton_Click(object sender, EventArgs e) {
+      if (ValidateChildren()) {
+        OnDialogValidated(this, e);
+        Close();
+      }
+    }
+  }
+}
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/displayModelFrame.html
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/displayModelFrame.html	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/HeuristicLab.Problems.DataAnalysis.Symbolic.Views/3.4/displayModelFrame.html	(revision 11010)
@@ -0,0 +1,53 @@
+﻿<!-- this file is derived from sample.html from the MathJax distribution -->
+<!-- Copyright (c) 2009-2011 Design Science, Inc. -->
+<!-- adapted by HEAL for HeuristicLab-->
+<!DOCTYPE html>
+<html>
+<head>
+  <!-- title change by HEAL -->
+  <title>Symbolic Expression Tree</title>
+  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+  <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" />
+  <script type="text/x-mathjax-config">
+  MathJax.Hub.Config({
+    extensions: ["tex2jax.js", "TeX/AMSmath.js", "TeX/AMSsymbols.js"],
+    jax: ["input/TeX","output/HTML-CSS"],
+    tex2jax: {inlineMath: [["$","$"],["\\(","\\)"]]},
+    imageFont: null
+  });
+  
+</script>
+  <script type="text/javascript" src="./MathJax.js"></script>
+  <!-- begin changes by HEAL -->
+  <script type="text/javascript">
+  function refreshModel() {
+    var model = document.getElementById("model");
+    MathJax.Hub.Queue(["Typeset",MathJax.Hub,model]);
+  }
+</script>
+  <!-- end changes by HEAL -->
+  <style>
+h1 {text-align:center}
+h2 {
+  font-weight: bold;
+  background-color: #DDDDDD;
+  padding: .2em .5em;
+  margin-top: 1.5em;
+  border-top: 3px solid #666666;
+  border-bottom: 2px solid #999999;
+}
+</style>
+</head>
+<body id="body">
+  <noscript>
+    <div style="color: #CC0000; text-align: center">
+      <b>Warning: <a href="http://www.mathjax.org/">MathJax</a> requires JavaScript to process
+        the mathematics on this page.<br />
+        If your browser supports JavaScript, be sure it is enabled.</b>
+    </div>
+    <hr>
+  </noscript>
+  <p id="model">
+  </p>
+</body>
+</html>
Index: /branches/HeuristicLab.InteractiveTreeSimplifier/PreBuildEvent.cmd
===================================================================
--- /branches/HeuristicLab.InteractiveTreeSimplifier/PreBuildEvent.cmd	(revision 11010)
+++ /branches/HeuristicLab.InteractiveTreeSimplifier/PreBuildEvent.cmd	(revision 11010)
@@ -0,0 +1,11 @@
+IF EXIST "%ProjectDir%\Properties\AssemblyInfo.cs.frame" SubWCRev "%ProjectDir%\" "%ProjectDir%\Properties\AssemblyInfo.cs.frame" "%ProjectDir%\Properties\AssemblyInfo.cs"
+IF %ERRORLEVEL% NEQ 0 GOTO Error_Handling
+IF EXIST "%ProjectDir%\Plugin.cs.frame" SubWCRev "%ProjectDir%\" "%ProjectDir%\Plugin.cs.frame" "%ProjectDir%\Plugin.cs"
+IF %ERRORLEVEL% NEQ 0 GOTO Error_Handling
+GOTO Done
+
+:Error_Handling
+ECHO There was an error while running subwcrev. Please verify that the *.cs.frame files have been correctly converted to *.cs files, otherwise HeuristicLab won't build. 
+exit 0
+
+:Done
