Changeset 14758 for branches/symbreg-factors-2650/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Symbols/FactorVariableTreeNode.cs

Timestamp:

03/18/17 10:36:37 (7 years ago)

Author:

gkronber

Message:

#2650 unified mutation behaviour for all variable tree nodes. Introduced parameter for probability of changing a variable.

File:

• branches/symbreg-factors-2650/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Symbols/FactorVariableTreeNode.cs (modified) (2 diffs)

branches/symbreg-factors-2650/HeuristicLab.Problems.DataAnalysis.Symbolic/3.4/Symbols/FactorVariableTreeNode.cs

@@ -75 +75 @@
 
     public override void ShakeLocalParameters(IRandom random, double shakingFactor) {
-      if(random.NextDouble() < 0.2) {
+      // mutate only one randomly selected weight
+      var idx = random.Next(weights.Length);
+      // 50% additive & 50% multiplicative
+      if(random.NextDouble() < 0.5) {
+        double x = NormalDistributedRandom.NextDouble(random, Symbol.WeightManipulatorMu,
+          Symbol.WeightManipulatorSigma);
+        weights[idx] = weights[idx] + x * shakingFactor;
+      } else {
+        double x = NormalDistributedRandom.NextDouble(random, 1.0, Symbol.MultiplicativeWeightManipulatorSigma);
+        weights[idx] = weights[idx] * x;
+      }
+      if(random.NextDouble() < Symbol.VariableChangeProbability) {
         VariableName = Symbol.VariableNames.SampleRandom(random);
         if(weights.Length != Symbol.GetVariableValues(VariableName).Count()) {
@@ -83 +94 @@
               .Select(_ => NormalDistributedRandom.NextDouble(random, 0, 1))
               .ToArray();
-        }
-      } else {
-        // mutate only one randomly selected weight
-        var idx = random.Next(weights.Length);
-        // 50% additive & 50% multiplicative
-        if(random.NextDouble() < 0.5) {
-          double x = NormalDistributedRandom.NextDouble(random, Symbol.WeightManipulatorMu,
-            Symbol.WeightManipulatorSigma);
-          weights[idx] = weights[idx] + x * shakingFactor;
-        } else {
-          double x = NormalDistributedRandom.NextDouble(random, 1.0, Symbol.MultiplicativeWeightManipulatorSigma);
-          weights[idx] = weights[idx] * x;
         }
       }