Changeset 5971

Timestamp:

04/07/11 07:49:15 (14 years ago)

Author:

gkronber

Message:

#1418 added a parameter to the symbol frequency analyzer in symbolic expression tree encoding which indicates if the frequencies of symbols with the same name but different number of subtrees should be aggregated.

File:

• trunk/sources/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Analyzers/SymbolicExpressionSymbolFrequencyAnalyzer.cs (modified) (7 diffs)

trunk/sources/HeuristicLab.Encodings.SymbolicExpressionTreeEncoding/3.4/Analyzers/SymbolicExpressionSymbolFrequencyAnalyzer.cs

@@ -29 +29 @@
 using HeuristicLab.Parameters;
 using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
+using HeuristicLab.Data;
 
 namespace HeuristicLab.Encodings.SymbolicExpressionTreeEncoding {
@@ -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) {
@@ -75 +81 @@
       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 +110 @@
     }
 
-    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 +116 @@
       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++;
         }