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source: branches/2521_ProblemRefactoring/HeuristicLab.Problems.Knapsack/3.3/KnapsackProblem.cs @ 16532

Last change on this file since 16532 was 16532, checked in by abeham, 5 years ago

#2521: reverted r14429

File size: 11.3 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2015 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.Analysis;
26using HeuristicLab.Common;
27using HeuristicLab.Core;
28using HeuristicLab.Data;
29using HeuristicLab.Encodings.BinaryVectorEncoding;
30using HeuristicLab.Optimization;
31using HeuristicLab.Optimization.Operators;
32using HeuristicLab.Parameters;
33using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
34
35namespace HeuristicLab.Problems.Knapsack {
36  [Item("Knapsack Problem (KSP)", "Represents a Knapsack problem.")]
37  [Creatable(CreatableAttribute.Categories.CombinatorialProblems, Priority = 200)]
38  [StorableClass]
39  public sealed class KnapsackProblem : SingleObjectiveProblem<BinaryVectorEncoding, BinaryVector> {
40    public override bool Maximization { get { return true; } }
41
42    #region Parameter Properties
43    public ValueParameter<IntValue> KnapsackCapacityParameter {
44      get { return (ValueParameter<IntValue>)Parameters["KnapsackCapacity"]; }
45    }
46    public ValueParameter<IntArray> WeightsParameter {
47      get { return (ValueParameter<IntArray>)Parameters["Weights"]; }
48    }
49    public ValueParameter<IntArray> ValuesParameter {
50      get { return (ValueParameter<IntArray>)Parameters["Values"]; }
51    }
52    public OptionalValueParameter<BinaryVector> BestKnownSolutionParameter {
53      get { return (OptionalValueParameter<BinaryVector>)Parameters["BestKnownSolution"]; }
54    }
55    #endregion
56
57    #region Properties
58    public int KnapsackCapacity {
59      get { return KnapsackCapacityParameter.Value.Value; }
60      set { KnapsackCapacityParameter.Value.Value = value; }
61    }
62    public IntArray Weights {
63      get { return WeightsParameter.Value; }
64      set { WeightsParameter.Value = value; }
65    }
66    public IntArray Values {
67      get { return ValuesParameter.Value; }
68      set { ValuesParameter.Value = value; }
69    }
70    public BinaryVector BestKnownSolution {
71      get { return BestKnownSolutionParameter.Value; }
72      set { BestKnownSolutionParameter.Value = value; }
73    }
74    private BestKnapsackSolutionAnalyzer BestKnapsackSolutionAnalyzer {
75      get { return Operators.OfType<BestKnapsackSolutionAnalyzer>().FirstOrDefault(); }
76    }
77    #endregion
78
79    [StorableConstructor]
80    private KnapsackProblem(bool deserializing) : base(deserializing) { }
81    private KnapsackProblem(KnapsackProblem original, Cloner cloner)
82      : base(original, cloner) {
83      RegisterEventHandlers();
84    }
85    public KnapsackProblem()
86      : base(new BinaryVectorEncoding("Selection")) {
87      Parameters.Add(new ValueParameter<IntValue>("KnapsackCapacity", "Capacity of the Knapsack.", new IntValue(1)));
88      Parameters.Add(new ValueParameter<IntArray>("Weights", "The weights of the items.", new IntArray(5)));
89      Parameters.Add(new ValueParameter<IntArray>("Values", "The values of the items.", new IntArray(5)));
90      Parameters.Add(new OptionalValueParameter<BinaryVector>("BestKnownSolution", "The best known solution of this Knapsack instance."));
91
92      InitializeRandomKnapsackInstance();
93
94      InitializeOperators();
95      RegisterEventHandlers();
96    }
97
98    public override double Evaluate(BinaryVector solution, IRandom random) {
99      var totalWeight = 0.0;
100      var totalValue = 0.0;
101      for (var i = 0; i < solution.Length; i++) {
102        if (!solution[i]) continue;
103        totalWeight += Weights[i];
104        totalValue += Values[i];
105      }
106      return totalWeight > KnapsackCapacity ? KnapsackCapacity - totalWeight : totalValue;
107    }
108
109    public override IDeepCloneable Clone(Cloner cloner) {
110      return new KnapsackProblem(this, cloner);
111    }
112
113    [StorableHook(HookType.AfterDeserialization)]
114    private void AfterDeserialization() {
115      RegisterEventHandlers();
116    }
117
118    private void RegisterEventHandlers() {
119      Evaluator.QualityParameter.ActualNameChanged += Evaluator_QualityParameter_ActualNameChanged;
120      KnapsackCapacityParameter.ValueChanged += KnapsackCapacityParameter_ValueChanged;
121      WeightsParameter.ValueChanged += WeightsParameter_ValueChanged;
122      WeightsParameter.Value.Reset += WeightsValue_Reset;
123      ValuesParameter.ValueChanged += ValuesParameter_ValueChanged;
124      ValuesParameter.Value.Reset += ValuesValue_Reset;
125      // TODO: There is no even to detect if the parameter itself was changed
126      Encoding.LengthParameter.ValueChanged += Encoding_LengthParameter_ValueChanged;
127    }
128
129    #region Events
130    protected override void OnEncodingChanged() {
131      base.OnEncodingChanged();
132      Parameterize();
133    }
134    //TODO check with abeham if this is really necessary
135    //protected override void OnSolutionCreatorChanged() {
136    //  base.OnSolutionCreatorChanged();
137    //  Parameterize();
138    //}
139    protected override void OnEvaluatorChanged() {
140      base.OnEvaluatorChanged();
141      Evaluator.QualityParameter.ActualNameChanged += Evaluator_QualityParameter_ActualNameChanged;
142      Parameterize();
143    }
144    private void Evaluator_QualityParameter_ActualNameChanged(object sender, EventArgs e) {
145      Parameterize();
146    }
147    private void KnapsackCapacityParameter_ValueChanged(object sender, EventArgs e) {
148      Parameterize();
149    }
150    private void WeightsParameter_ValueChanged(object sender, EventArgs e) {
151      Parameterize();
152      WeightsParameter.Value.Reset += WeightsValue_Reset;
153    }
154    private void WeightsValue_Reset(object sender, EventArgs e) {
155      if (WeightsParameter.Value != null && ValuesParameter.Value != null) {
156        ((IStringConvertibleArray)ValuesParameter.Value).Length = Weights.Length;
157        Encoding.Length = Weights.Length;
158      }
159      Parameterize();
160    }
161    private void ValuesParameter_ValueChanged(object sender, EventArgs e) {
162      Parameterize();
163      ValuesParameter.Value.Reset += ValuesValue_Reset;
164    }
165    private void ValuesValue_Reset(object sender, EventArgs e) {
166      if (WeightsParameter.Value != null && ValuesParameter.Value != null) {
167        ((IStringConvertibleArray)WeightsParameter.Value).Length = Values.Length;
168        Encoding.Length = Values.Length;
169      }
170      Parameterize();
171    }
172    private void Encoding_LengthParameter_ValueChanged(object sender, EventArgs e) {
173      if (Weights.Length != Encoding.Length) {
174        ((IStringConvertibleArray)WeightsParameter.Value).Length = Encoding.Length;
175      }
176      if (Values.Length != Encoding.Length) {
177        ((IStringConvertibleArray)ValuesParameter.Value).Length = Encoding.Length;
178      }
179      Parameterize();
180    }
181    #endregion
182
183    #region Helpers
184    private void InitializeOperators() {
185      Operators.Add(new KnapsackImprovementOperator());
186      Operators.Add(new KnapsackPathRelinker());
187      Operators.Add(new KnapsackSimultaneousPathRelinker());
188      Operators.Add(new KnapsackSimilarityCalculator());
189      Operators.Add(new QualitySimilarityCalculator());
190      Operators.Add(new NoSimilarityCalculator());
191
192      Operators.Add(new BestKnapsackSolutionAnalyzer());
193      Operators.Add(new PopulationSimilarityAnalyzer(Operators.OfType<ISolutionSimilarityCalculator>()));
194
195      Parameterize();
196    }
197    private void Parameterize() {
198      var operators = new List<IItem>();
199
200      if (BestKnapsackSolutionAnalyzer != null) {
201        operators.Add(BestKnapsackSolutionAnalyzer);
202        BestKnapsackSolutionAnalyzer.MaximizationParameter.ActualName = MaximizationParameter.Name;
203        BestKnapsackSolutionAnalyzer.MaximizationParameter.Hidden = true;
204        BestKnapsackSolutionAnalyzer.BestKnownQualityParameter.ActualName = BestKnownQualityParameter.Name;
205        BestKnapsackSolutionAnalyzer.BestKnownQualityParameter.Hidden = true;
206        BestKnapsackSolutionAnalyzer.BestKnownSolutionParameter.ActualName = BestKnownSolutionParameter.Name;
207        BestKnapsackSolutionAnalyzer.BestKnownSolutionParameter.Hidden = true;
208        BestKnapsackSolutionAnalyzer.KnapsackCapacityParameter.ActualName = KnapsackCapacityParameter.Name;
209        BestKnapsackSolutionAnalyzer.KnapsackCapacityParameter.Hidden = true;
210        BestKnapsackSolutionAnalyzer.WeightsParameter.ActualName = WeightsParameter.Name;
211        BestKnapsackSolutionAnalyzer.WeightsParameter.Hidden = true;
212        BestKnapsackSolutionAnalyzer.ValuesParameter.ActualName = ValuesParameter.Name;
213        BestKnapsackSolutionAnalyzer.ValuesParameter.Hidden = true;
214      }
215      foreach (var op in Operators.OfType<IKnapsackMoveEvaluator>()) {
216        operators.Add(op);
217        op.KnapsackCapacityParameter.ActualName = KnapsackCapacityParameter.Name;
218        op.KnapsackCapacityParameter.Hidden = true;
219        op.WeightsParameter.ActualName = WeightsParameter.Name;
220        op.WeightsParameter.Hidden = true;
221        op.ValuesParameter.ActualName = ValuesParameter.Name;
222        op.ValuesParameter.Hidden = true;
223
224        var bitflipMoveEval = op as IKnapsackOneBitflipMoveEvaluator;
225        if (bitflipMoveEval != null) {
226          foreach (var moveOp in Encoding.Operators.OfType<IOneBitflipMoveQualityOperator>()) {
227            moveOp.MoveQualityParameter.ActualName = bitflipMoveEval.MoveQualityParameter.ActualName;
228            moveOp.MoveQualityParameter.Hidden = true;
229          }
230        }
231      }
232      foreach (var op in Operators.OfType<ISingleObjectiveImprovementOperator>()) {
233        operators.Add(op);
234        op.SolutionParameter.ActualName = Encoding.Name;
235        op.SolutionParameter.Hidden = true;
236      }
237      foreach (var op in Operators.OfType<ISingleObjectivePathRelinker>()) {
238        operators.Add(op);
239        op.ParentsParameter.ActualName = Encoding.Name;
240        op.ParentsParameter.Hidden = true;
241      }
242      foreach (var op in Operators.OfType<ISolutionSimilarityCalculator>()) {
243        operators.Add(op);
244        op.SolutionVariableName = Encoding.Name;
245        op.QualityVariableName = Evaluator.QualityParameter.ActualName;
246      }
247
248      if (operators.Count > 0) Encoding.ConfigureOperators(Operators);
249    }
250    #endregion
251
252    private void InitializeRandomKnapsackInstance() {
253      var sysrand = new System.Random();
254
255      var itemCount = sysrand.Next(10, 100);
256      Weights = new IntArray(itemCount);
257      Values = new IntArray(itemCount);
258
259      double totalWeight = 0;
260
261      for (int i = 0; i < itemCount; i++) {
262        var value = sysrand.Next(1, 10);
263        var weight = sysrand.Next(1, 10);
264
265        Values[i] = value;
266        Weights[i] = weight;
267        totalWeight += weight;
268      }
269
270      KnapsackCapacity = (int)Math.Round(0.7 * totalWeight);
271    }
272  }
273}
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