Index: branches/ExportSymbolicDataAnalysisSolutions/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Formatters/SymbolicDataAnalysisExpressionExcelFormatter.cs
===================================================================
--- branches/ExportSymbolicDataAnalysisSolutions/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Formatters/SymbolicDataAnalysisExpressionExcelFormatter.cs	(revision 9580)
+++ branches/ExportSymbolicDataAnalysisSolutions/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Formatters/SymbolicDataAnalysisExpressionExcelFormatter.cs	(revision 9580)
@@ -0,0 +1,362 @@
+﻿#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.Globalization;
+using System.Text;
+using HeuristicLab.Common;
+using HeuristicLab.Core;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic {
+  [Item("Excel String Formatter", "String formatter for string representations of symbolic data analysis expressions in Excel syntax.")]
+  [StorableClass]
+  public sealed class SymbolicDataAnalysisExpressionExcelFormatter : NamedItem, ISymbolicExpressionTreeStringFormatter {
+    //private int currentLag;
+
+    [StorableConstructor]
+    private SymbolicDataAnalysisExpressionExcelFormatter(bool deserializing) : base(deserializing) { }
+    private SymbolicDataAnalysisExpressionExcelFormatter(SymbolicDataAnalysisExpressionExcelFormatter original, Cloner cloner) : base(original, cloner) { }
+    public SymbolicDataAnalysisExpressionExcelFormatter()
+      : base() {
+      Name = ItemName;
+      Description = ItemDescription;
+    }
+    public override IDeepCloneable Clone(Cloner cloner) {
+      return new SymbolicDataAnalysisExpressionExcelFormatter(this, cloner);
+    }
+    private string GetExcelColumnName(int columnNumber) {
+      int dividend = columnNumber;
+      string columnName = String.Empty;
+
+      while (dividend > 0) {
+        int modulo = (dividend - 1) % 26;
+        columnName = Convert.ToChar(65 + modulo).ToString() + columnName;
+        dividend = (int)((dividend - modulo) / 26);
+      }
+
+      return columnName;
+    }
+
+    private readonly Dictionary<string, string> variableNameMapping = new Dictionary<string, string>();
+    private int currentVariableIndex = 0;
+    private string GetColumnToVariableName(string variabelName) {
+      if (!variableNameMapping.ContainsKey(variabelName)) {
+        currentVariableIndex++;
+        variableNameMapping.Add(variabelName, GetExcelColumnName(currentVariableIndex));
+      }
+      return string.Format("${0}1", variableNameMapping[variabelName]);
+    }
+    //public string CurrentIndexVariable {
+    //  get {
+    //    return "i" + currentIndexNumber;
+    //  }
+    //}
+    //private void ReleaseIndexVariable() {
+    //  currentIndexNumber--;
+    //}
+
+    //private string AllocateIndexVariable() {
+    //  currentIndexNumber++;
+    //  return CurrentIndexVariable;
+    //}
+
+    public string Format(ISymbolicExpressionTree symbolicExpressionTree) {
+      var stringBuilder = new StringBuilder();
+      stringBuilder.Append("=");
+      stringBuilder.Append(FormatRecursively(symbolicExpressionTree.Root));
+      foreach (var variable in variableNameMapping) {
+        stringBuilder.AppendLine();
+        stringBuilder.Append(variable.Key + " = " + variable.Value);
+      }
+      return stringBuilder.ToString();
+    }
+
+    private string FormatRecursively(ISymbolicExpressionTreeNode node) {
+      ISymbol symbol = node.Symbol;
+      StringBuilder stringBuilder = new StringBuilder();
+
+      if (symbol is ProgramRootSymbol) {
+        stringBuilder.AppendLine(FormatRecursively(node.GetSubtree(0)));
+      } else if (symbol is StartSymbol)
+        return FormatRecursively(node.GetSubtree(0));
+      else if (symbol is Addition) {
+        stringBuilder.Append("(");
+        for (int i = 0; i < node.SubtreeCount; i++) {
+          if (i > 0) stringBuilder.Append("+");
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+        }
+        stringBuilder.Append(")");
+        //} else if (symbol is And) {
+        //  stringBuilder.Append("((");
+        //  for (int i = 0; i < node.SubtreeCount; i++) {
+        //    if (i > 0) stringBuilder.Append("&");
+        //    stringBuilder.Append("((");
+        //    stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+        //    stringBuilder.Append(")>0)");
+        //  }
+        //  stringBuilder.Append(")-0.5)*2");
+        //  // MATLAB maps false and true to 0 and 1, resp., we map this result to -1.0 and +1.0, resp.
+      } else if (symbol is Average) {
+        stringBuilder.Append("(1/");
+        stringBuilder.Append(node.SubtreeCount);
+        stringBuilder.Append(")*(");
+        for (int i = 0; i < node.SubtreeCount; i++) {
+          if (i > 0) stringBuilder.Append("+");
+          stringBuilder.Append("(");
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+          stringBuilder.Append(")");
+        }
+        stringBuilder.Append(")");
+      } else if (symbol is Constant) {
+        ConstantTreeNode constantTreeNode = node as ConstantTreeNode;
+        stringBuilder.Append(constantTreeNode.Value.ToString(CultureInfo.InvariantCulture));
+      } else if (symbol is Cosine) {
+        stringBuilder.Append("COS(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(")");
+      } else if (symbol is Division) {
+        if (node.SubtreeCount == 1) {
+          stringBuilder.Append("1/");
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        } else {
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+          stringBuilder.Append("/(");
+          for (int i = 1; i < node.SubtreeCount; i++) {
+            if (i > 1) stringBuilder.Append("*");
+            stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+          }
+          stringBuilder.Append(")");
+        }
+      } else if (symbol is Exponential) {
+        stringBuilder.Append("EXP(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(")");
+      } else if (symbol is Square) {
+        stringBuilder.Append("POWER(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(",2)");
+      } else if (symbol is SquareRoot) {
+        stringBuilder.Append("SQRT(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(")");
+        //} else if (symbol is GreaterThan) {
+        //  stringBuilder.Append("((");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(">");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(1)));
+        //  stringBuilder.Append(")-0.5)*2");
+        //  // MATLAB maps false and true to 0 and 1, resp., we map this result to -1.0 and +1.0, resp.
+        //} else if (symbol is IfThenElse) {
+        //  stringBuilder.Append("(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(">0)*");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(1)));
+        //  stringBuilder.Append("+");
+        //  stringBuilder.Append("(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append("<=0)*");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(2)));
+        //} else if (symbol is LaggedVariable) {
+        //  // this if must be checked before if(symbol is LaggedVariable)
+        //  LaggedVariableTreeNode laggedVariableTreeNode = node as LaggedVariableTreeNode;
+        //  stringBuilder.Append(laggedVariableTreeNode.Weight.ToString(CultureInfo.InvariantCulture));
+        //  stringBuilder.Append("*");
+        //  stringBuilder.Append(laggedVariableTreeNode.VariableName +
+        //                       LagToString(currentLag + laggedVariableTreeNode.Lag));
+        //} else if (symbol is LessThan) {
+        //  stringBuilder.Append("((");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append("<");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(1)));
+        //  stringBuilder.Append(")-0.5)*2");
+        //  // MATLAB maps false and true to 0 and 1, resp., we map this result to -1.0 and +1.0, resp.
+      } else if (symbol is Logarithm) {
+        stringBuilder.Append("LOG(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(", EXP(1))"); // Excel does not use the natural logarithm, therefor the base has to be set
+      } else if (symbol is Multiplication) {
+        for (int i = 0; i < node.SubtreeCount; i++) {
+          if (i > 0) stringBuilder.Append("*");
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+        }
+        //} else if (symbol is Not) {
+        //  stringBuilder.Append("NOT(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(" > 0 )");
+        //} else if (symbol is Or) {
+        //  stringBuilder.Append("((");
+        //  for (int i = 0; i < node.SubtreeCount; i++) {
+        //    if (i > 0) stringBuilder.Append("|");
+        //    stringBuilder.Append("((");
+        //    stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+        //    stringBuilder.Append(")>0)");
+        //  }
+        //  stringBuilder.Append(")-0.5)*2");
+        //  // MATLAB maps false and true to 0 and 1, resp., we map this result to -1.0 and +1.0, resp.
+      } else if (symbol is Sine) {
+        stringBuilder.Append("SIN(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(")");
+      } else if (symbol is Subtraction) {
+        stringBuilder.Append("(");
+        if (node.SubtreeCount == 1) {
+          stringBuilder.Append("-");
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        } else {
+          stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+          for (int i = 1; i < node.SubtreeCount; i++) {
+            stringBuilder.Append("-");
+            stringBuilder.Append(FormatRecursively(node.GetSubtree(i)));
+          }
+        }
+        stringBuilder.Append(")");
+      } else if (symbol is Tangent) {
+        stringBuilder.Append("TAN(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(")");
+        //} else if (node.Symbol is AiryA) {
+        //  stringBuilder.Append("airy(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is AiryB) {
+        //  stringBuilder.Append("airy(2, ");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is Bessel) {
+        //  stringBuilder.Append("besseli(0.0,");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is CosineIntegral) {
+        //  stringBuilder.Append("cosint(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is Dawson) {
+        //  stringBuilder.Append("dawson(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is Erf) {
+        //  stringBuilder.Append("erf(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is ExponentialIntegralEi) {
+        //  stringBuilder.Append("expint(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is FresnelCosineIntegral) {
+        //  stringBuilder.Append("FresnelC(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is FresnelSineIntegral) {
+        //  stringBuilder.Append("FresnelS(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is Gamma) {
+        //  stringBuilder.Append("gamma(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is HyperbolicCosineIntegral) {
+        //  stringBuilder.Append("Chi(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is HyperbolicSineIntegral) {
+        //  stringBuilder.Append("Shi(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is Norm) {
+        //  stringBuilder.Append("normpdf(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is Psi) {
+        //  stringBuilder.Append("psi(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //} else if (node.Symbol is SineIntegral) {
+        //  stringBuilder.Append("sinint(");
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+      } else if (symbol is HeuristicLab.Problems.DataAnalysis.Symbolic.Variable) {
+        VariableTreeNode variableTreeNode = node as VariableTreeNode;
+        stringBuilder.Append(variableTreeNode.Weight.ToString(CultureInfo.InvariantCulture));
+        stringBuilder.Append("*");
+        stringBuilder.Append(GetColumnToVariableName(variableTreeNode.VariableName));// + LagToString(currentLag));
+      } else if (symbol is Power) {
+        stringBuilder.Append("POWER(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(",ROUND(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(1)));
+        stringBuilder.Append(",0))");
+      } else if (symbol is Root) {
+        stringBuilder.Append("(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        stringBuilder.Append(")^(1 / ROUND(");
+        stringBuilder.Append(FormatRecursively(node.GetSubtree(1)));
+        stringBuilder.Append(",0))");
+        //} else if (symbol is Derivative) {
+        //  stringBuilder.Append("fivePoint(");
+        //  // f0
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(", ");
+        //  // f1
+        //  currentLag--;
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(", ");
+        //  // f3
+        //  currentLag -= 2;
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(", ");
+        //  currentLag--;
+        //  // f4
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //  stringBuilder.Append(")");
+        //  currentLag += 4;
+        //} else if (symbol is Integral) {
+        //  var laggedNode = node as LaggedTreeNode;
+        //  string prevCounterVariable = CurrentIndexVariable;
+        //  string counterVariable = AllocateIndexVariable();
+        //  stringBuilder.AppendLine(" sum (map(@(" + counterVariable + ") " + FormatRecursively(node.GetSubtree(0)) +
+        //                           ", (" + prevCounterVariable + "+" + laggedNode.Lag + "):" + prevCounterVariable +
+        //                           "))");
+        //  ReleaseIndexVariable();
+        //} else if (symbol is TimeLag) {
+        //  var laggedNode = node as LaggedTreeNode;
+        //  currentLag += laggedNode.Lag;
+        //  stringBuilder.Append(FormatRecursively(node.GetSubtree(0)));
+        //currentLag -= laggedNode.Lag;
+      } else {
+        stringBuilder.Append("ERROR");
+      }
+      return stringBuilder.ToString();
+    }
+
+
+    //private string LagToString(int lag) {
+    //  if (lag < 0) {
+    //    return "(" + CurrentIndexVariable + "" + lag + ")";
+    //  } else if (lag > 0) {
+    //    return "(" + CurrentIndexVariable + "+" + lag + ")";
+    //  } else return "(" + CurrentIndexVariable + ")";
+    //}
+
+  }
+}
Index: branches/ExportSymbolicDataAnalysisSolutions/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/HeuristicLab.Problems.DataAnalysis.Symbolic-3.4.csproj
===================================================================
--- branches/ExportSymbolicDataAnalysisSolutions/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/HeuristicLab.Problems.DataAnalysis.Symbolic-3.4.csproj	(revision 9514)
+++ branches/ExportSymbolicDataAnalysisSolutions/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/HeuristicLab.Problems.DataAnalysis.Symbolic-3.4.csproj	(revision 9580)
@@ -203,4 +203,5 @@
     <Compile Include="Crossovers\SymbolicDataAnalysisExpressionProbabilisticFunctionalCrossover.cs" />
     <Compile Include="Crossovers\SymbolicDataAnalysisExpressionSemanticSimilarityCrossover.cs" />
+    <Compile Include="Formatters\SymbolicDataAnalysisExpressionExcelFormatter.cs" />
     <Compile Include="Interfaces\ISymbolicDataAnalysisExpressionCrossover.cs" />
     <Compile Include="Interfaces\ISymbolicDataAnalysisImpactValuesCalculator.cs" />
