source: branches/HeuristicLab.EvolutionaryTracking/HeuristicLab.EvolutionaryTracking/3.4/Analyzers/SymbolicExpressionTreePopulationDiversityAnalyzer.cs @ 9238

#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2012 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System.Linq;
using HeuristicLab.Analysis;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;
using HeuristicLab.Operators;
using HeuristicLab.Optimization;
using HeuristicLab.Parameters;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Problems.DataAnalysis.Symbolic;

// type definitions for ease of use
using CloneMapType = HeuristicLab.Core.ItemDictionary<HeuristicLab.Core.IItem, HeuristicLab.Core.IItem>;

namespace HeuristicLab.EvolutionaryTracking {
  /// <summary>
  /// Population diversity analyzer
  /// </summary>
  [Item("SymbolicExpressionTreePopulationDiversityAnalyzer", "An operator that tracks population diversity")]
  [StorableClass]
  public sealed class SymbolicExpressionTreePopulationDiversityAnalyzer : SingleSuccessorOperator, IAnalyzer {
    #region Parameter names
    private const string SymbolicExpressionTreeParameterName = "SymbolicExpressionTree";
    private const string UpdateIntervalParameterName = "UpdateInterval";
    private const string UpdateCounterParameterName = "UpdateCounter";
    private const string ResultsParameterName = "Results";
    private const string GenerationsParameterName = "Generations";
    private const string StoreHistoryParameterName = "StoreHistory";
    // comparer parameters
    private const string MatchVariablesParameterName = "MatchVariableNames";
    private const string MatchVariableWeightsParameterName = "MatchVariableWeights";
    private const string MatchConstantValuesParameterName = "MatchConstantValues";
    private const string SortSubtreesParameterName = "SortSubtrees";
    // population graph
    private const string PopulationGraphParameterName = "PopulationGraph";
    // clone map
    private const string GlobalCloneMapParameterName = "GlobalCloneMap";
    #endregion

    #region Parameters
    public ValueParameter<IntValue> UpdateIntervalParameter {
      get { return (ValueParameter<IntValue>)Parameters[UpdateIntervalParameterName]; }
    }
    public ValueParameter<IntValue> UpdateCounterParameter {
      get { return (ValueParameter<IntValue>)Parameters[UpdateCounterParameterName]; }
    }
    public LookupParameter<ResultCollection> ResultsParameter {
      get { return (LookupParameter<ResultCollection>)Parameters[ResultsParameterName]; }
    }
    public LookupParameter<IntValue> GenerationsParameter {
      get { return (LookupParameter<IntValue>)Parameters[GenerationsParameterName]; }
    }
    public ValueParameter<BoolValue> StoreHistoryParameter {
      get { return (ValueParameter<BoolValue>)Parameters[StoreHistoryParameterName]; }
    }
    public IScopeTreeLookupParameter<ISymbolicExpressionTree> SymbolicExpressionTreeParameter {
      get { return (IScopeTreeLookupParameter<ISymbolicExpressionTree>)Parameters[SymbolicExpressionTreeParameterName]; }
    }
    public ValueParameter<BoolValue> MatchVariableNamesParameter {
      get { return (ValueParameter<BoolValue>)Parameters[MatchVariablesParameterName]; }
    }
    public ValueParameter<BoolValue> MatchVariableWeightsParameter {
      get { return (ValueParameter<BoolValue>)Parameters[MatchVariableWeightsParameterName]; }
    }
    public ValueParameter<BoolValue> MatchConstantValuesParameter {
      get { return (ValueParameter<BoolValue>)Parameters[MatchConstantValuesParameterName]; }
    }
    public ValueParameter<BoolValue> SortSubtreesParameter {
      get { return (ValueParameter<BoolValue>)Parameters[SortSubtreesParameterName]; }
    }
    public LookupParameter<CloneMapType> GlobalCloneMapParameter {
      get { return (LookupParameter<CloneMapType>)Parameters[GlobalCloneMapParameterName]; }
    }
    #endregion

    #region Parameter properties
    public IntValue UpdateInterval {
      get { return UpdateIntervalParameter.Value; }
    }
    public IntValue UpdateCounter {
      get { return UpdateCounterParameter.Value; }
    }
    public ResultCollection Results {
      get { return ResultsParameter.ActualValue; }
    }
    public CloneMapType GlobalCloneMap {
      get { return GlobalCloneMapParameter.ActualValue; }
    }
    public IntValue Generations {
      get { return GenerationsParameter.ActualValue; }
    }
    public BoolValue StoreHistory {
      get { return StoreHistoryParameter.Value; }
    }
    #endregion

    [StorableConstructor]
    private SymbolicExpressionTreePopulationDiversityAnalyzer(bool deserializing) : base(deserializing) { }
    private SymbolicExpressionTreePopulationDiversityAnalyzer(SymbolicExpressionTreePopulationDiversityAnalyzer original, Cloner cloner) : base(original, cloner) { }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new SymbolicExpressionTreePopulationDiversityAnalyzer(this, cloner);
    }
    public SymbolicExpressionTreePopulationDiversityAnalyzer() {
      // add parameters
      Parameters.Add(new ScopeTreeLookupParameter<ISymbolicExpressionTree>(SymbolicExpressionTreeParameterName, "The symbolic expression trees to analyze."));
      Parameters.Add(new ValueParameter<IntValue>(UpdateIntervalParameterName, "The interval in which the tree length analysis should be applied.", new IntValue(1)));
      Parameters.Add(new ValueParameter<IntValue>(UpdateCounterParameterName, "The value which counts how many times the operator was called since the last update", new IntValue(0)));
      Parameters.Add(new ValueLookupParameter<ResultCollection>(ResultsParameterName, "The results collection where the analysis values should be stored."));
      Parameters.Add(new LookupParameter<IntValue>(GenerationsParameterName, "The number of generations so far."));
      Parameters.Add(new ValueParameter<BoolValue>(MatchVariablesParameterName, "Specify if the symbolic expression tree comparer should match variable names."));
      Parameters.Add(new ValueParameter<BoolValue>(MatchVariableWeightsParameterName, "Specify if the symbolic expression tree comparer should match variable weights."));
      Parameters.Add(new ValueParameter<BoolValue>(MatchConstantValuesParameterName, "Specify if the symbolic expression tree comparer should match constant values."));
      Parameters.Add(new ValueParameter<BoolValue>(SortSubtreesParameterName, "Specifies whether the subtrees of a tree should be sorted before comparison."));
      Parameters.Add(new LookupParameter<CloneMapType>(GlobalCloneMapParameterName, "A global map keeping track of trees and their clones (made during selection)."));
      Parameters.Add(new ValueParameter<BoolValue>(StoreHistoryParameterName, "True if the tree lengths history of the population should be stored.", new BoolValue(false)));
      UpdateCounterParameter.Hidden = true;
      UpdateIntervalParameter.Hidden = true;
    }
    [StorableHook(HookType.AfterDeserialization)]
    private void AfterDeserialization() { }

    #region IStatefulItem members
    public override void InitializeState() {
      base.InitializeState();
      UpdateCounter.Value = 0;
    }

    public override void ClearState() {
      base.ClearState();
      UpdateCounter.Value = 0;
    }
    #endregion

    public bool EnabledByDefault { get { return true; } }

    public override IOperation Apply() {
      UpdateCounter.Value++;

      if (UpdateCounter.Value == UpdateInterval.Value) {
        UpdateCounter.Value = 0;

        var trees = SymbolicExpressionTreeParameter.ActualValue.ToList();
        if (SortSubtreesParameter.Value.Value) {
          var canonicalSorter = new SymbolicExpressionTreeCanonicalSorter();
          foreach (var t in trees) canonicalSorter.SortSubtrees(t);
        }

        bool matchConstants = MatchConstantValuesParameter.Value.Value;
        bool matchVarNames = MatchVariableNamesParameter.Value.Value;
        bool matchVarWeights = MatchVariableWeightsParameter.Value.Value;

        var comparer = new SymbolicExpressionTreeEqualityComparer {
          SimilarityComparer = new SymbolicExpressionTreeNodeSimilarityComparer {
            MatchConstantValues = matchConstants, MatchVariableNames = matchVarNames, MatchVariableWeights = matchVarWeights
          }
        };
        ResultCollection results = ResultsParameter.ActualValue;
        // population diversity
        DataTable populationDiversityTable;
        if (!results.ContainsKey("PopulationDiversity")) {
          populationDiversityTable = new DataTable("PopulationDiversity") { VisualProperties = { YAxisTitle = "Diversity" } };
          results.Add(new Result("PopulationDiversity", populationDiversityTable));
        }
        populationDiversityTable = (DataTable)results["PopulationDiversity"].Value;
        if (!populationDiversityTable.Rows.ContainsKey("Diversity"))
          populationDiversityTable.Rows.Add(new DataRow("Diversity") { VisualProperties = { StartIndexZero = true } });
        double distinct = trees.Distinct(comparer).Count() / (double)trees.Count;
        populationDiversityTable.Rows["Diversity"].Values.Add(distinct);
        // selection diversity
        if (GlobalCloneMap == null) return base.Apply();

        DataTable relativeSelectionCountsTable;
        if (!results.ContainsKey("SelectedIndividuals")) {
          relativeSelectionCountsTable = new DataTable("SelectedIndividuals") { VisualProperties = { YAxisTitle = "% Selected Individuals" } };
          results.Add(new Result("SelectedIndividuals", relativeSelectionCountsTable));
        }
        relativeSelectionCountsTable = (DataTable)Results["SelectedIndividuals"].Value;
        if (!relativeSelectionCountsTable.Rows.ContainsKey("SelectedIndividuals")) {
          relativeSelectionCountsTable.Rows.Add(new DataRow("SelectedIndividuals") { VisualProperties = { StartIndexZero = true } });
        }
        double relativeSelectionCount = GlobalCloneMap.Values.Distinct().Count() / (double)trees.Count;
        relativeSelectionCountsTable.Rows["SelectedIndividuals"].Values.Add(relativeSelectionCount);

        // do a histogram of selection frequency for each individual in the population
        DataTable selectionFrequenciesTable;
        if (!results.ContainsKey("SelectionFrequencies")) {
          selectionFrequenciesTable = new DataTable("Selection Frequencies") { VisualProperties = { YAxisTitle = "Selection Count" } };
          results.Add(new Result("SelectionFrequencies", selectionFrequenciesTable));
        }
        selectionFrequenciesTable = (DataTable)results["SelectionFrequencies"].Value;
        DataRow histoRow;
        if (!selectionFrequenciesTable.Rows.ContainsKey("SelectionFrequencies")) {
          histoRow = new DataRow("SelectionFrequencies") { VisualProperties = { StartIndexZero = true } };
          selectionFrequenciesTable.Rows.Add(histoRow);
        }
        histoRow = selectionFrequenciesTable.Rows["SelectionFrequencies"];
        var frequencies = new double[trees.Count];

        var graph = (SymbolicExpressionTreeGenealogyGraph)results[PopulationGraphParameterName].Value;
        // get graph nodes corresponding to individuals of the previous generation
        var prevGen = graph.Nodes.Where(node => node.Rank == Generations.Value - 1).OrderByDescending(n => n.Quality).ToList();
        for (int i = 0; i != prevGen.Count; ++i) {
          int selFreq = GlobalCloneMap.Values.Count(t => t == prevGen[i].SymbolicExpressionTree);
          frequencies[i] = selFreq;
        }
        histoRow.Values.Replace(frequencies);

        bool storeHistory = StoreHistory.Value;
        if (storeHistory) {
          DataTableHistory selectionFrequenciesHistory;
          if (!results.ContainsKey("SelectionFrequenciesHistory")) {
            selectionFrequenciesHistory = new DataTableHistory();
            results.Add(new Result("SelectionFrequenciesHistory", selectionFrequenciesHistory));
          }
          selectionFrequenciesHistory = (DataTableHistory)results["SelectionFrequenciesHistory"].Value;
          selectionFrequenciesHistory.Add((DataTable)selectionFrequenciesTable.Clone());
        }
      }
      return base.Apply();
    }
  }
}