Changeset 11847 for branches/HeuristicLab.Problems.GrammaticalOptimization/HeuristicLab.Problems.GrammaticalOptimization/Problems/SantaFeAntProblem.cs

Timestamp:

02/01/15 19:49:25 (9 years ago)

Author:

gkronber

Message:

#2283 various fixes for tree-based GP

File:

• branches/HeuristicLab.Problems.GrammaticalOptimization/HeuristicLab.Problems.GrammaticalOptimization/Problems/SantaFeAntProblem.cs (modified) (4 diffs)

branches/HeuristicLab.Problems.GrammaticalOptimization/HeuristicLab.Problems.GrammaticalOptimization/Problems/SantaFeAntProblem.cs

@@ -1 +1 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Runtime.InteropServices;
@@ -6 +7 @@
 using System.Text;
 using System.Text.RegularExpressions;
+using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
 
 namespace HeuristicLab.Problems.GrammaticalOptimization {
-  public class SantaFeAntProblem : IProblem {
+  public class SantaFeAntProblem : ISymbolicExpressionTreeProblem {
     private const string grammarString = @"
 G(A):
 A -> l | r | m | ?(A)(A) | lA | rA | mA 
 ";
+    // for tree-based GP in HL we need a different grammar for the same language
+    // A = Ant, P = Prog2 and Prog3, I = IfFoodAhead
+    private const string hlGrammarString = @"
+    G(A):
+    A -> l | r | m | P | I
+    P -> AA | AAA
+    I -> AA
+    ";
 
 
@@ -25 +35 @@
     public SantaFeAntProblem() {
       this.grammar = new Grammar(grammarString);
+      this.SymbolicExpressionGrammar = new GenericSymbExprGrammar(new Grammar(hlGrammarString));
     }
 
@@ -116 +127 @@
     public IEnumerable<Feature> GetFeatures(string phrase) {
       return Enumerable.Repeat(new Feature(CanonicalRepresentation(phrase), 1.0), 1);
+    }
+
+    public ISymbolicExpressionGrammar SymbolicExpressionGrammar { get; private set; }
+    public string ConvertTreeToSentence(ISymbolicExpressionTree tree) {
+      var sb = new StringBuilder();
+      ConvertTreeToSentence(tree.Root.GetSubtree(0).GetSubtree(0), sb);
+      return sb.ToString();
+    }
+    private void ConvertTreeToSentence(ISymbolicExpressionTreeNode node, StringBuilder sb) {
+      if (node.SubtreeCount == 0) {
+        // terminal
+        sb.Append(node.Symbol.Name);
+      } else if (node.Symbol.Name == "I") {
+        Debug.Assert(node.SubtreeCount == 2);
+        sb.Append("?(");
+        ConvertTreeToSentence(node.GetSubtree(0), sb);
+        sb.Append(")(");
+        ConvertTreeToSentence(node.GetSubtree(1), sb);
+        sb.Append(")");
+      } else {
+        foreach (var subTree in node.Subtrees) { ConvertTreeToSentence(subTree, sb); }
+      }
     }
   }