Changeset 6011 for branches/histogram/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding

Timestamp:

04/15/11 14:54:43 (13 years ago)

Author:

abeham

Message:

#1465

• updated branch with changes from trunk
• fixed some bugs
• introduced secondary x-axis option

Location:

branches/histogram

Files:

• . (modified) (1 prop)
• HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Analyzers/SymbolicExpressionSymbolFrequencyAnalyzer.cs (modified) (7 diffs)
• HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Creators/ProbabilisticTreeCreator.cs (modified) (3 diffs)
• HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/SymbolicExpressionGrammarBase.cs (modified) (4 diffs)

branches/histogram/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Analyzers/SymbolicExpressionSymbolFrequencyAnalyzer.cs

@@ -25 +25 @@
 using HeuristicLab.Common;
 using HeuristicLab.Core;
+using HeuristicLab.Data;
 using HeuristicLab.Operators;
 using HeuristicLab.Optimization;
@@ -40 +41 @@
     private const string ResultsParameterName = "Results";
     private const string SymbolFrequenciesParameterName = "SymbolFrequencies";
+    private const string AggregateSymbolsWithDifferentSubtreeCountParameterName = "AggregateSymbolsWithDifferentSubtreeCount";
 
     #region parameter properties
@@ -51 +53 @@
       get { return (ILookupParameter<ResultCollection>)Parameters[ResultsParameterName]; }
     }
+    public IValueParameter<BoolValue> AggregateSymbolsWithDifferentSubtreeCountParameter {
+      get { return (IValueParameter<BoolValue>)Parameters[AggregateSymbolsWithDifferentSubtreeCountParameterName]; }
+    }
     #endregion
     #region properties
-    public DataTable SymbolFrequencies {
-      get { return SymbolFrequenciesParameter.ActualValue; }
-      set { SymbolFrequenciesParameter.ActualValue = value; }
+    public BoolValue AggregrateSymbolsWithDifferentSubtreeCount {
+      get { return AggregateSymbolsWithDifferentSubtreeCountParameter.Value; }
+      set { AggregateSymbolsWithDifferentSubtreeCountParameter.Value = value; }
     }
     #endregion
@@ -65 +70 @@
       : base() {
       Parameters.Add(new ScopeTreeLookupParameter<ISymbolicExpressionTree>(SymbolicExpressionTreeParameterName, "The symbolic expression trees to analyze."));
-      Parameters.Add(new ValueLookupParameter<DataTable>(SymbolFrequenciesParameterName, "The data table to store the symbol frequencies."));
+      Parameters.Add(new LookupParameter<DataTable>(SymbolFrequenciesParameterName, "The data table to store the symbol frequencies."));
       Parameters.Add(new LookupParameter<ResultCollection>(ResultsParameterName, "The result collection where the symbol frequencies should be stored."));
+      Parameters.Add(new ValueParameter<BoolValue>(AggregateSymbolsWithDifferentSubtreeCountParameterName, "Flag that indicates if the frequencies of symbols with the same name but different number of sub-trees should be aggregated.", new BoolValue(true)));
     }
     public override IDeepCloneable Clone(Cloner cloner) {
@@ -72 +78 @@
     }
 
+    [StorableHook(HookType.AfterDeserialization)]
+    private void AfterDeserialization() {
+      #region remove with HL 3.4
+      if (!Parameters.ContainsKey(AggregateSymbolsWithDifferentSubtreeCountParameterName))
+        Parameters.Add(new ValueParameter<BoolValue>(AggregateSymbolsWithDifferentSubtreeCountParameterName, "Flag that indicates if the frequencies of symbols with the same name but different number of sub-trees should be aggregated.", new BoolValue(true)));
+      #endregion
+    }
+
     public override IOperation Apply() {
       ItemArray<ISymbolicExpressionTree> expressions = SymbolicExpressionTreeParameter.ActualValue;
       ResultCollection results = ResultsParameter.ActualValue;
+      DataTable symbolFrequencies = SymbolFrequenciesParameter.ActualValue;
+      if (symbolFrequencies == null) {
+        symbolFrequencies = new DataTable("Symbol frequencies", "Relative frequency of symbols aggregated over the whole population.");
+        symbolFrequencies.VisualProperties.YAxisTitle = "Relative Symbol Frequency";
 
-      if (SymbolFrequencies == null) {
-        SymbolFrequencies = new DataTable("Symbol frequencies", "Relative frequency of symbols aggregated over the whole population.");
-        SymbolFrequencies.VisualProperties.YAxisTitle = "Relative Symbol Frequency";
-        results.Add(new Result("Symbol frequencies", SymbolFrequencies));
+        SymbolFrequenciesParameter.ActualValue = symbolFrequencies;
+        results.Add(new Result("Symbol frequencies", symbolFrequencies));
       }
 
       // all rows must have the same number of values so we can just take the first
-      int numberOfValues = SymbolFrequencies.Rows.Select(r => r.Values.Count).DefaultIfEmpty().First();
+      int numberOfValues = symbolFrequencies.Rows.Select(r => r.Values.Count).DefaultIfEmpty().First();
 
-      foreach (var pair in SymbolicExpressionSymbolFrequencyAnalyzer.CalculateSymbolFrequencies(expressions)) {
-        if (!SymbolFrequencies.Rows.ContainsKey(pair.Key)) {
+      foreach (var pair in SymbolicExpressionSymbolFrequencyAnalyzer.CalculateSymbolFrequencies(expressions, AggregrateSymbolsWithDifferentSubtreeCount.Value)) {
+        if (!symbolFrequencies.Rows.ContainsKey(pair.Key)) {
           // initialize a new row for the symbol and pad with zeros
           DataRow row = new DataRow(pair.Key, "", Enumerable.Repeat(0.0, numberOfValues));
           row.VisualProperties.StartIndexZero = true;
-          SymbolFrequencies.Rows.Add(row);
+          symbolFrequencies.Rows.Add(row);
         }
-        SymbolFrequencies.Rows[pair.Key].Values.Add(pair.Value);
+        symbolFrequencies.Rows[pair.Key].Values.Add(pair.Value);
       }
 
       // add a zero for each data row that was not modified in the previous loop 
-      foreach (var row in SymbolFrequencies.Rows.Where(r => r.Values.Count != numberOfValues + 1))
+      foreach (var row in symbolFrequencies.Rows.Where(r => r.Values.Count != numberOfValues + 1))
         row.Values.Add(0.0);
 
@@ -102 +118 @@
     }
 
-    public static IEnumerable<KeyValuePair<string, double>> CalculateSymbolFrequencies(IEnumerable<ISymbolicExpressionTree> trees) {
+    public static IEnumerable<KeyValuePair<string, double>> CalculateSymbolFrequencies(IEnumerable<ISymbolicExpressionTree> trees, bool aggregateDifferentNumberOfSubtrees = true) {
       Dictionary<string, double> symbolFrequencies = new Dictionary<string, double>();
       int totalNumberOfSymbols = 0;
@@ -108 +124 @@
       foreach (var tree in trees) {
         foreach (var node in tree.IterateNodesPrefix()) {
-          if (symbolFrequencies.ContainsKey(node.Symbol.Name)) symbolFrequencies[node.Symbol.Name] += 1;
-          else symbolFrequencies.Add(node.Symbol.Name, 1);
+          string symbolName;
+          if (aggregateDifferentNumberOfSubtrees) symbolName = node.Symbol.Name;
+          else symbolName = node.Symbol.Name + "-" + node.SubtreesCount;
+          if (symbolFrequencies.ContainsKey(symbolName)) symbolFrequencies[symbolName] += 1;
+          else symbolFrequencies.Add(symbolName, 1);
           totalNumberOfSymbols++;
         }

branches/histogram/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Creators/ProbabilisticTreeCreator.cs

@@ -103 +103 @@
     public static void PTC2(IRandom random, ISymbolicExpressionTreeNode seedNode,
       int maxLength, int maxDepth) {
+      // make sure it is possible to create a trees smaller than maxLength and maxDepth
+      if (seedNode.Grammar.GetMinimumExpressionLength(seedNode.Symbol) > maxLength)
+        throw new ArgumentException("Cannot create trees of length " + maxLength + " or shorter because of grammar constraints.", "maxLength");
+      if (seedNode.Grammar.GetMinimumExpressionDepth(seedNode.Symbol) > maxDepth)
+        throw new ArgumentException("Cannot create trees of depth " + maxDepth + " or smaller because of grammar constraints.", "maxDepth");
+
       // tree length is limited by the grammar and by the explicit size constraints
       int allowedMinLength = seedNode.Grammar.GetMinimumExpressionLength(seedNode.Symbol);
@@ -149 +155 @@
         int argumentIndex = nextExtension.ChildIndex;
         int extensionDepth = nextExtension.ExtensionPointDepth;
-        if (extensionDepth + parent.Grammar.GetMinimumExpressionDepth(parent.Symbol) >= maxDepth) {
+        if (parent.Grammar.GetMinimumExpressionDepth(parent.Symbol) >= maxDepth - extensionDepth) {
           ReplaceWithMinimalTree(random, root, parent, argumentIndex);
         } else {
@@ -155 +161 @@
                                 where s.InitialFrequency > 0.0
                                 where parent.Grammar.IsAllowedChildSymbol(parent.Symbol, s, argumentIndex)
-                                where parent.Grammar.GetMinimumExpressionDepth(s) + extensionDepth - 1 < maxDepth
+                                where parent.Grammar.GetMinimumExpressionDepth(s) < maxDepth - extensionDepth + 1
                                 where parent.Grammar.GetMaximumExpressionLength(s) > targetLength - totalListMinLength - currentLength
                                 select s)

branches/histogram/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/SymbolicExpressionGrammarBase.cs

@@ -229 +229 @@
 
     public virtual IEnumerable<ISymbol> GetAllowedChildSymbols(ISymbol parent) {
-      return from s in Symbols where IsAllowedChildSymbol(parent, s) select s;
+      return from s in AllowedSymbols where IsAllowedChildSymbol(parent, s) select s;
     }
 
@@ -265 +265 @@
         cachedMinExpressionLength[symbol.Name] = int.MaxValue; // prevent infinite recursion
         long sumOfMinExpressionLengths = 1 + (from argIndex in Enumerable.Range(0, GetMinimumSubtreeCount(symbol))
-                                              let minForSlot = (long)(from s in Symbols
+                                              let minForSlot = (long)(from s in AllowedSymbols
                                                                       where IsAllowedChildSymbol(symbol, s, argIndex)
                                                                       select GetMinimumExpressionLength(s)).DefaultIfEmpty(0).Min()
@@ -282 +282 @@
         cachedMaxExpressionLength[symbol.Name] = int.MaxValue; // prevent infinite recursion
         long sumOfMaxTrees = 1 + (from argIndex in Enumerable.Range(0, GetMaximumSubtreeCount(symbol))
-                                  let maxForSlot = (long)(from s in Symbols
+                                  let maxForSlot = (long)(from s in AllowedSymbols
                                                           where IsAllowedChildSymbol(symbol, s, argIndex)
                                                           select GetMaximumExpressionLength(s)).DefaultIfEmpty(0).Max()
                                   select maxForSlot).DefaultIfEmpty(0).Sum();
-        long limit = int.MaxValue;
-        cachedMaxExpressionLength[symbol.Name] = (int)Math.Min(sumOfMaxTrees, limit);
+        cachedMaxExpressionLength[symbol.Name] = (int)Math.Min(sumOfMaxTrees, int.MaxValue);
         return cachedMaxExpressionLength[symbol.Name];
       }
@@ -298 +297 @@
       if (!cachedMinExpressionDepth.TryGetValue(symbol.Name, out temp)) {
         cachedMinExpressionDepth[symbol.Name] = int.MaxValue; // prevent infinite recursion
-        cachedMinExpressionDepth[symbol.Name] = 1 + (from argIndex in Enumerable.Range(0, GetMinimumSubtreeCount(symbol))
-                                                     let minForSlot = (from s in Symbols
-                                                                       where IsAllowedChildSymbol(symbol, s, argIndex)
-                                                                       select GetMinimumExpressionDepth(s)).DefaultIfEmpty(0).Min()
-                                                     select minForSlot).DefaultIfEmpty(0).Max();
+        long minDepth = 1 + (from argIndex in Enumerable.Range(0, GetMinimumSubtreeCount(symbol))
+                             let minForSlot = (long)(from s in AllowedSymbols
+                                                     where IsAllowedChildSymbol(symbol, s, argIndex)
+                                                     select GetMinimumExpressionDepth(s)).DefaultIfEmpty(0).Min()
+                             select minForSlot).DefaultIfEmpty(0).Max();
+        cachedMinExpressionDepth[symbol.Name] = (int)Math.Min(minDepth, int.MaxValue);
         return cachedMinExpressionDepth[symbol.Name];
       }