Index: trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Formatters/SymbolicExpressionTreeLatexFormatter.cs
===================================================================
--- trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Formatters/SymbolicExpressionTreeLatexFormatter.cs	(revision 5428)
+++ trunk/sources/HeuristicLab.Problems.DataAnalysis/3.3/Symbolic/Formatters/SymbolicExpressionTreeLatexFormatter.cs	(revision 5428)
@@ -0,0 +1,302 @@
+﻿#region License Information
+/* HeuristicLab
+ * Copyright (C) 2002-2010 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.Text;
+using System.Linq;
+using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
+using System.Collections.Generic;
+using HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols;
+using System;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding.Symbols;
+using HeuristicLab.Core;
+using HeuristicLab.Common;
+
+namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Formatters {
+  [Item("LaTeX String Formatter", "Formatter for symbolic expression trees for import into LaTeX documents.")]
+  public sealed class SymbolicExpressionTreeLatexFormatter : NamedItem, ISymbolicExpressionTreeStringFormatter {
+    private List<double> constants;
+    private int currentLag;
+
+    public SymbolicExpressionTreeLatexFormatter()
+      : base("LaTeX String Formatter", "Formatter for symbolic expression trees for import into LaTeX documents.") {
+      constants = new List<double>();
+    }
+    private SymbolicExpressionTreeLatexFormatter(SymbolicExpressionTreeLatexFormatter original, Cloner cloner)
+      : base(original, cloner) {
+      constants = new List<double>(original.constants);
+    }
+
+    public override IDeepCloneable Clone(Cloner cloner) {
+      return new SymbolicExpressionTreeLatexFormatter(this, cloner);
+    }
+
+    public string Format(SymbolicExpressionTree symbolicExpressionTree) {
+      try {
+        StringBuilder strBuilder = new StringBuilder();
+        constants.Clear();
+        strBuilder.AppendLine("% needs \\usepackage{amsmath}");
+        strBuilder.AppendLine("\\begin{align}");
+        strBuilder.AppendLine(FormatRecursively(symbolicExpressionTree.Root));
+        strBuilder.AppendLine("\\end{align}");
+        return strBuilder.ToString();
+      }
+      catch (NotImplementedException ex) {
+        return ex.Message + Environment.NewLine + ex.StackTrace;
+      }
+    }
+
+    private string FormatRecursively(SymbolicExpressionTreeNode node) {
+      StringBuilder strBuilder = new StringBuilder();
+      currentLag = 0;
+      FormatBegin(node, strBuilder);
+
+      if (node.SubTrees.Count > 0) {
+        strBuilder.Append(FormatRecursively(node.SubTrees[0]));
+      }
+      foreach (SymbolicExpressionTreeNode subTree in node.SubTrees.Skip(1)) {
+        FormatSep(node, strBuilder);
+        // format the whole subtree
+        strBuilder.Append(FormatRecursively(subTree));
+      }
+
+      FormatEnd(node, strBuilder);
+
+      return strBuilder.ToString();
+    }
+
+    private void FormatBegin(SymbolicExpressionTreeNode node, StringBuilder strBuilder) {
+      if (node.Symbol is Addition) {
+        strBuilder.Append(@" \left( ");
+      } else if (node.Symbol is Subtraction) {
+        if (node.SubTrees.Count == 1) {
+          strBuilder.Append(@"- \left(");
+        } else {
+          strBuilder.Append(@" \left( ");
+        }
+      } else if (node.Symbol is Multiplication) {
+      } else if (node.Symbol is Division) {
+        if (node.SubTrees.Count == 1) {
+          strBuilder.Append(@" \cfrac{1}{");
+        } else {
+          strBuilder.Append(@" \cfrac{ ");
+        }
+      } else if (node.Symbol is Average) {
+        // skip output of (1/1) if only one subtree
+        if (node.SubTrees.Count > 1) {
+          strBuilder.Append(@" \cfrac{1}{" + node.SubTrees.Count + @"}");
+        }
+        strBuilder.Append(@" \left(");
+      } else if (node.Symbol is Logarithm) {
+        strBuilder.Append(@"\log \left(");
+      } else if (node.Symbol is Exponential) {
+        strBuilder.Append(@"\exp \left(");
+      } else if (node.Symbol is Sine) {
+        strBuilder.Append(@"\sin \left(");
+      } else if (node.Symbol is Cosine) {
+        strBuilder.Append(@"\cos \left(");
+      } else if (node.Symbol is Tangent) {
+        strBuilder.Append(@"\tan \left(");
+      } else if (node.Symbol is GreaterThan) {
+        strBuilder.Append(@" \left( ");
+      } else if (node.Symbol is LessThan) {
+        strBuilder.Append(@" \left( ");
+      } else if (node.Symbol is And) {
+        strBuilder.Append(@" \left( \left( ");
+      } else if (node.Symbol is Or) {
+        strBuilder.Append(@" \left( \left( ");
+      } else if (node.Symbol is Not) {
+        strBuilder.Append(@" -1.0 \cdot \left( ");
+      } else if (node.Symbol is IfThenElse) {
+        strBuilder.Append(@"\left( \operatorname{if} \left( 0 < ");
+      } else if (node.Symbol is Constant) {
+        strBuilder.Append("c_{" + constants.Count + "} ");
+        var constNode = node as ConstantTreeNode;
+        constants.Add(constNode.Value);
+      } else if (node.Symbol is LaggedVariable) {
+        var laggedVarNode = node as LaggedVariableTreeNode;
+        strBuilder.Append("c_{" + constants.Count + "} " + laggedVarNode.VariableName);
+        strBuilder.Append(LagToString(currentLag + laggedVarNode.Lag));
+        constants.Add(laggedVarNode.Weight);
+      } else if (node.Symbol is HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols.Variable) {
+        var varNode = node as VariableTreeNode;
+        strBuilder.Append("c_{" + constants.Count + "} " + varNode.VariableName);
+        strBuilder.Append(LagToString(currentLag));
+        constants.Add(varNode.Weight);
+      } else if (node.Symbol is ProgramRootSymbol) {
+      } else if (node.Symbol is Defun) {
+        var defunNode = node as DefunTreeNode;
+        strBuilder.Append(defunNode.FunctionName + " & = ");
+      } else if (node.Symbol is InvokeFunction) {
+        var invokeNode = node as InvokeFunctionTreeNode;
+        strBuilder.Append(invokeNode.Symbol.FunctionName + @" \left( ");
+      } else if (node.Symbol is StartSymbol) {
+        strBuilder.Append("Result & = ");
+      } else if (node.Symbol is Argument) {
+        var argSym = node.Symbol as Argument;
+        strBuilder.Append(" ARG+" + argSym.ArgumentIndex + " ");
+      } else if (node.Symbol is Derivative) {
+        strBuilder.Append(@" \cfrac{d \left(");
+      } else if (node.Symbol is TimeLag) {
+        var laggedNode = node as ILaggedTreeNode;
+        currentLag += laggedNode.Lag;
+      } else if (node.Symbol is Power) {
+        strBuilder.Append(@"\left(");
+      } else if (node.Symbol is Root) {
+        strBuilder.Append(@"\left(");
+      } else if (node.Symbol is Integral) {
+        // actually a new variable for t is needed in all subtrees (TODO)
+        var laggedTreeNode = node as ILaggedTreeNode;
+        strBuilder.Append(@"\sum_{t=" + (laggedTreeNode.Lag + currentLag) + @"}^0 \left(");
+      } else {
+        throw new NotImplementedException("Export of " + node.Symbol + " is not implemented.");
+      }
+    }
+
+    private void FormatSep(SymbolicExpressionTreeNode node, StringBuilder strBuilder) {
+      if (node.Symbol is Addition) {
+        strBuilder.Append(" + ");
+      } else if (node.Symbol is Subtraction) {
+        strBuilder.Append(" - ");
+      } else if (node.Symbol is Multiplication) {
+        strBuilder.Append(@" \cdot ");
+      } else if (node.Symbol is Division) {
+        strBuilder.Append(@" }{ \cfrac{ ");
+      } else if (node.Symbol is Average) {
+        strBuilder.Append(@" + ");
+      } else if (node.Symbol is Logarithm) {
+        throw new InvalidOperationException();
+      } else if (node.Symbol is Exponential) {
+        throw new InvalidOperationException();
+      } else if (node.Symbol is Sine) {
+        throw new InvalidOperationException();
+      } else if (node.Symbol is Cosine) {
+        throw new InvalidOperationException();
+      } else if (node.Symbol is Tangent) {
+        throw new InvalidOperationException();
+      } else if (node.Symbol is GreaterThan) {
+        strBuilder.Append(@" > ");
+      } else if (node.Symbol is LessThan) {
+        strBuilder.Append(@" < ");
+      } else if (node.Symbol is And) {
+        strBuilder.Append(@" > 0 \right) \land \left(");
+      } else if (node.Symbol is Or) {
+        strBuilder.Append(@" > 0 \right) \lor \left(");
+      } else if (node.Symbol is Not) {
+        throw new InvalidOperationException();
+      } else if (node.Symbol is IfThenElse) {
+        strBuilder.Append(@" \right) , \left(");
+      } else if (node.Symbol is ProgramRootSymbol) {
+        strBuilder.Append(@"\\" + Environment.NewLine);
+      } else if (node.Symbol is Defun) {
+      } else if (node.Symbol is InvokeFunction) {
+        strBuilder.Append(" , ");
+      } else if (node.Symbol is StartSymbol) {
+        strBuilder.Append(@"\\" + Environment.NewLine + " & ");
+      } else if (node.Symbol is Power) {
+        strBuilder.Append(@"\right) ^ { \operatorname{round} \left(");
+      } else if (node.Symbol is Root) {
+        strBuilder.Append(@"\right) ^ { \left( \cfrac{1}{ \operatorname{round} \left(");
+      } else {
+        throw new NotImplementedException("Export of " + node.Symbol + " is not implemented.");
+      }
+    }
+
+    private void FormatEnd(SymbolicExpressionTreeNode node, StringBuilder strBuilder) {
+      if (node.Symbol is Addition) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is Subtraction) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is Multiplication) {
+      } else if (node.Symbol is Division) {
+        strBuilder.Append("} ");
+        if (node.SubTrees.Count > 1)
+          strBuilder.Append("{1} ");
+        for (int i = 1; i < node.SubTrees.Count; i++) {
+          strBuilder.Append(" } ");
+        }
+      } else if (node.Symbol is Average) {
+        strBuilder.Append(@" \right)");
+      } else if (node.Symbol is Logarithm) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is Exponential) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is Sine) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is Cosine) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is Tangent) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is GreaterThan) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is LessThan) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is And) {
+        strBuilder.Append(@" > 0 \right) \right) ");
+      } else if (node.Symbol is Or) {
+        strBuilder.Append(@" > 0 \right) \right) ");
+      } else if (node.Symbol is Not) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is IfThenElse) {
+        strBuilder.Append(@" \right) \right) ");
+      } else if (node.Symbol is Constant) {
+      } else if (node.Symbol is LaggedVariable) {
+      } else if (node.Symbol is HeuristicLab.Problems.DataAnalysis.Symbolic.Symbols.Variable) {
+      } else if (node.Symbol is ProgramRootSymbol) {
+        // output all constant values
+        if (constants.Count > 0) {
+          int i = 0;
+          foreach (var constant in constants) {
+            strBuilder.AppendLine(@"\\");
+            strBuilder.Append("c_{" + i + "} & = " + constant);
+            i++;
+          }
+        }
+      } else if (node.Symbol is Defun) {
+      } else if (node.Symbol is InvokeFunction) {
+        strBuilder.Append(@" \right) ");
+      } else if (node.Symbol is StartSymbol) {
+      } else if (node.Symbol is Argument) {
+      } else if (node.Symbol is Derivative) {
+        strBuilder.Append(@" \right) }{dt} ");
+      } else if (node.Symbol is TimeLag) {
+        var laggedNode = node as ILaggedTreeNode;
+        currentLag -= laggedNode.Lag;
+      } else if (node.Symbol is Power) {
+        strBuilder.Append(@"\right) } ");
+      } else if (node.Symbol is Root) {
+        strBuilder.Append(@"\right) } \right) } ");
+      } else if (node.Symbol is Integral) {
+        var laggedTreeNode = node as ILaggedTreeNode;
+        strBuilder.Append(@"\right) ");
+      } else {
+        throw new NotImplementedException("Export of " + node.Symbol + " is not implemented.");
+      }
+    }
+    private string LagToString(int lag) {
+      if (lag < 0) {
+        return "(t" + lag + ")";
+      } else if (lag > 0) {
+        return "(t+" + lag + ")";
+      } else return "(t)";
+    }
+  }
+}
