Changeset 8214 for branches/GP-MoveOperators/HeuristicLab.Problems.DataAnalysis.Symbolic.Regression/3.4/ReplaceBranchMoveMaker.cs

Timestamp:

07/04/12 16:23:35 (12 years ago)

Author:

gkronber

Message:

#1847: bug fixes and improvements discussed with andreas

File:

• branches/GP-MoveOperators/HeuristicLab.Problems.DataAnalysis.Symbolic.Regression/3.4/ReplaceBranchMoveMaker.cs (modified) (1 diff)

branches/GP-MoveOperators/HeuristicLab.Problems.DataAnalysis.Symbolic.Regression/3.4/ReplaceBranchMoveMaker.cs

@@ -86 +86 @@
 
     private ISymbolicExpressionTreeNode Scale(ISymbolicExpressionTreeNode node, double alpha, double beta) {
-      var constAlpha = (ConstantTreeNode)constant.CreateTreeNode();
-      var constBeta = (ConstantTreeNode)constant.CreateTreeNode();
-      constAlpha.Value = alpha;
-      constBeta.Value = beta;
-      var sum = add.CreateTreeNode();
-      var prod = mul.CreateTreeNode();
-      prod.AddSubtree(node); prod.AddSubtree(constBeta);
-      sum.AddSubtree(prod); sum.AddSubtree(constAlpha);
-      return sum;
+      var constNode = node as ConstantTreeNode;
+      if (constNode != null) {
+        constNode.Value = constNode.Value * beta + alpha;
+        return constNode;
+      }
+      var varNode = node as VariableTreeNode;
+      if (varNode != null) {
+        varNode.Weight = varNode.Weight * beta;
+        var constAlpha = (ConstantTreeNode)constant.CreateTreeNode();
+        constAlpha.Value = alpha;
+        var sum = add.CreateTreeNode();
+        sum.AddSubtree(varNode); sum.AddSubtree(constAlpha);
+        return sum;
+      }
+      if (node.Symbol is Addition && node.GetSubtree(0).Symbol is Multiplication &&
+        node.GetSubtree(1).Symbol is Constant && node.GetSubtree(0).GetSubtree(1).Symbol is Constant) {
+        var constAlpha = node.GetSubtree(1) as ConstantTreeNode;
+        var constBeta = node.GetSubtree(0).GetSubtree(1) as ConstantTreeNode;
+        constAlpha.Value = beta * constAlpha.Value + alpha;
+        constBeta.Value = constBeta.Value * beta;
+        return node;
+      } else {
+        var constAlpha = (ConstantTreeNode)constant.CreateTreeNode();
+        var constBeta = (ConstantTreeNode)constant.CreateTreeNode();
+        constAlpha.Value = alpha;
+        constBeta.Value = beta;
+        var sum = add.CreateTreeNode();
+        var prod = mul.CreateTreeNode();
+        prod.AddSubtree(node);
+        prod.AddSubtree(constBeta);
+        sum.AddSubtree(prod);
+        sum.AddSubtree(constAlpha);
+        return sum;
+      }
     }
   }