source: branches/LearningClassifierSystems/HeuristicLab.Optimization.Operators.LCS/3.3/Selection/NichingTournamentSelector.cs @ 9475

Last change on this file since 9475 was 9475, checked in by sforsten, 8 years ago

#1980: several small bug fixes

File size: 6.8 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2012 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
4 *
5 * This file is part of HeuristicLab.
6 *
7 * HeuristicLab is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * HeuristicLab is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
19 */
20#endregion
21
22using System;
23using System.Collections.Generic;
24using System.Linq;
25using HeuristicLab.Common;
26using HeuristicLab.Core;
27using HeuristicLab.Data;
28using HeuristicLab.Parameters;
29using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
30using HeuristicLab.Selection;
31
32namespace HeuristicLab.Optimization.Operators.LCS {
33  [Item("NichingTournamentSelector", "Description missing")]
34  [StorableClass]
35  public class NichingTournamentSelector : StochasticSingleObjectiveSelector, INichingSingleObjectiveSelector {
36
37    #region Parameter Properties
38    public ValueLookupParameter<IntValue> GroupSizeParameter {
39      get { return (ValueLookupParameter<IntValue>)Parameters["GroupSize"]; }
40    }
41    public ILookupParameter<IGAssistProblemData> GAssistNichesProblemDataParameter {
42      get { return (LookupParameter<IGAssistProblemData>)Parameters["GAssistNichesProblemData"]; }
43    }
44    public ILookupParameter<BoolValue> NichingParameter {
45      get { return (LookupParameter<BoolValue>)Parameters["Niching"]; }
46    }
47    public IValueLookupParameter<IntValue> ParentsPerChildParameter {
48      get { return (IValueLookupParameter<IntValue>)Parameters["ParentsPerChild"]; }
49    }
50    public ILookupParameter<ItemArray<IGAssistIndividual>> IndividualParameter {
51      get { return (ILookupParameter<ItemArray<IGAssistIndividual>>)Parameters["Individual"]; }
52    }
53    #endregion
54
55    [StorableConstructor]
56    protected NichingTournamentSelector(bool deserializing) : base(deserializing) { }
57    protected NichingTournamentSelector(NichingTournamentSelector original, Cloner cloner)
58      : base(original, cloner) {
59    }
60    public NichingTournamentSelector()
61      : base() {
62      Parameters.Add(new ValueLookupParameter<IntValue>("GroupSize", "The size of the tournament group.", new IntValue(2)));
63      Parameters.Add(new LookupParameter<IGAssistProblemData>("GAssistNichesProblemData", ""));
64      Parameters.Add(new LookupParameter<BoolValue>("Niching", ""));
65      Parameters.Add(new ValueLookupParameter<IntValue>("ParentsPerChild", ""));
66      Parameters.Add(new ScopeTreeLookupParameter<IGAssistIndividual>("Individual", ""));
67    }
68    public override IDeepCloneable Clone(Cloner cloner) {
69      return new NichingTournamentSelector(this, cloner);
70    }
71
72    protected override IScope[] Select(List<IScope> scopes) {
73      int count = NumberOfSelectedSubScopesParameter.ActualValue.Value;
74      bool copy = CopySelectedParameter.Value.Value;
75      IRandom random = RandomParameter.ActualValue;
76      bool maximization = MaximizationParameter.ActualValue.Value;
77      List<double> qualities = QualityParameter.ActualValue.Where(x => IsValidQuality(x.Value)).Select(x => x.Value).ToList();
78      List<IGAssistIndividual> individuals = IndividualParameter.ActualValue.ToList();
79      int groupSize = GroupSizeParameter.ActualValue.Value;
80      IScope[] selected = new IScope[count];
81      bool doNiching = NichingParameter.ActualValue.Value;
82
83      //check if list with indexes is as long as the original scope list
84      //otherwise invalid quality values were filtered
85      if (qualities.Count != scopes.Count || individuals.Count != scopes.Count) {
86        throw new ArgumentException("The scopes contain invalid quality values (either infinity or double.NaN) on which the selector cannot operate.");
87      }
88
89      int parentsPerChild = ParentsPerChildParameter.ActualValue.Value;
90      var nicheComparer = GAssistNichesProblemDataParameter.ActualValue.GetPossibleNiches().First().Comparer;
91      var selectPerNiche = new Dictionary<IGAssistNiche, int>(nicheComparer);
92      var nicheScope = new Dictionary<IGAssistNiche, List<int>>(nicheComparer);
93
94      for (int i = 0; i < individuals.Count; i++) {
95        if (!nicheScope.ContainsKey(individuals[i].Niche)) {
96          nicheScope.Add(individuals[i].Niche, new List<int>());
97        }
98        nicheScope[individuals[i].Niche].Add(i);
99      }
100
101      var possibleNiches = nicheScope.Keys.ToList();
102      foreach (var niche in possibleNiches) {
103        selectPerNiche.Add(niche, count / possibleNiches.Count);
104      }
105
106      int curCount = 0;
107      while (curCount < count) {
108        IGAssistNiche niche = null;
109        int best = -1;
110        if (doNiching) {
111          niche = GetNiche(random, selectPerNiche, possibleNiches);
112        } else {
113          best = random.Next(scopes.Count);
114        }
115        for (int i = 0; i < parentsPerChild; i++) {
116          int index;
117          if (doNiching) {
118            best = nicheScope[niche][random.Next(nicheScope[niche].Count)];
119          }
120          for (int j = 1; j < groupSize; j++) {
121            if (niche != null) {
122              index = nicheScope[niche][random.Next(nicheScope[niche].Count)];
123            } else {
124              index = random.Next(scopes.Count);
125            }
126            if (((maximization) && (qualities[index] > qualities[best])) ||
127                ((!maximization) && (qualities[index] < qualities[best]))) {
128              best = index;
129            }
130          }
131
132          niche = individuals[best].Niche;
133
134          if (copy)
135            selected[curCount] = (IScope)scopes[best].Clone();
136          else {
137            selected[curCount] = scopes[best];
138            scopes.RemoveAt(best);
139            qualities.RemoveAt(best);
140          }
141          selectPerNiche[niche]--;
142          curCount++;
143        }
144      }
145      return selected;
146    }
147
148    private IGAssistNiche GetNiche(IRandom random, Dictionary<IGAssistNiche, int> selectPerNiche, List<IGAssistNiche> possibleNiches) {
149      int sum = selectPerNiche.Values.Sum();
150      if (sum <= 0) { return possibleNiches[random.Next(possibleNiches.Count)]; }
151      int pos = random.Next(sum);
152      int total = 0;
153      IGAssistNiche niche = selectPerNiche.Keys.First();
154      foreach (var item in selectPerNiche) {
155        total += item.Value;
156        niche = item.Key;
157        if (pos < total) {
158          return niche;
159        }
160      }
161      throw new ArgumentException("error in code");
162    }
163  }
164}
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