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source: branches/VRP/HeuristicLab.Problems.VehicleRouting/3.3/Encodings/Prins/Manipulators/PrinsExhaustiveLSManipulator.cs @ 4268

Last change on this file since 4268 was 4268, checked in by svonolfe, 14 years ago

Added prins encoding (#1039)

File size: 2.7 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2010 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 HeuristicLab.Core;
23using HeuristicLab.Encodings.PermutationEncoding;
24using HeuristicLab.Parameters;
25using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
26using HeuristicLab.Data;
27using System.Collections.Generic;
28
29namespace HeuristicLab.Problems.VehicleRouting.Encodings.Prins {
30  [Item("PrinsExhaustiveLSManipulator", "An operator which manipulates a VRP representation by using the exhaustive Prins local search.  It is implemented as described in Prins, C. (2004). A simple and effective evolutionary algorithm for the vehicle routing problem. Computers & Operations Research, 12:1985-2002.")]
31  [StorableClass]
32  public sealed class PrinsExhaustiveLSManipulator : PrinsLSManipulator {   
33    [StorableConstructor]
34    private PrinsExhaustiveLSManipulator(bool deserializing) : base(deserializing) { }
35
36    public PrinsExhaustiveLSManipulator()
37      : base() {
38    }
39
40    protected override void Manipulate(IRandom random, PrinsEncoding individual) {
41      List<Tour> tours = individual.GetTours(DistanceMatrixParameter);
42      bool improvement = false;
43      int iterations = 0;
44
45      do {
46        int u = depot;
47        improvement = false;
48        double originalQuality = GetQuality(individual);
49        PrinsEncoding child = null;
50
51        while (!improvement && u < Cities) {
52          int v = depot;
53          while (!improvement && v < Cities) {
54            if (u != v) {
55              child = Manipulate(individual,
56                originalQuality, u, v);
57
58              improvement = child != null;
59            }
60            v++;
61          }
62          u++;
63        }
64
65        if (improvement) {
66          for (int i = 0; i < child.Length; i++) {
67            individual[i] = child[i];
68          }
69        }
70
71        iterations++;
72      } while (improvement &&
73        iterations < Iterations.Value.Value);
74    }
75  }
76}
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