Free cookie consent management tool by TermsFeed Policy Generator

source: branches/VRP/HeuristicLab.Problems.VehicleRouting/3.4/Encodings/Zhu/Crossovers/ZhuHeuristicCrossover1.cs @ 4379

Last change on this file since 4379 was 4379, checked in by svonolfe, 14 years ago

Added remaining encodings (#1177)

File size: 3.2 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;
27
28namespace HeuristicLab.Problems.VehicleRouting.Encodings.Zhu {
29  [Item("ZhuHeuristicCrossover1", "The Zhu Heuristic Crossover (Version 1). It is implemented as described in Zhu, K.Q. (2000). A New Genetic Algorithm For VRPTW. Proceedings of the International Conference on Artificial Intelligence.")]
30  [StorableClass]
31  public sealed class ZhuHeuristicCrossover1 : ZhuCrossover {   
32    [StorableConstructor]
33    private ZhuHeuristicCrossover1(bool deserializing) : base(deserializing) { }
34
35    public ZhuHeuristicCrossover1()
36      : base() {
37    }
38
39    private void Swap(ZhuEncoding individual, int city1, int city2) {
40      int index1 = individual.IndexOf(city1);
41      int index2 = individual.IndexOf(city2);
42
43      int temp = individual[index1];
44      individual[index1] = individual[index2];
45      individual[index2] = temp;
46    }
47
48    protected override ZhuEncoding Crossover(IRandom random, ZhuEncoding parent1, ZhuEncoding parent2) {
49      parent1 = parent1.Clone() as ZhuEncoding;
50      parent2 = parent2.Clone() as ZhuEncoding;
51
52      ZhuEncoding child = parent2.Clone() as ZhuEncoding;
53
54      int breakPoint = random.Next(child.Length);
55      int i = breakPoint;
56      int predecessor = breakPoint - 1;
57      if (predecessor < 0)
58        predecessor = predecessor + child.Length;
59
60      while (i != predecessor) {
61        if (i == breakPoint) {
62          child[i] = parent1[i];
63          Swap(parent2, parent2[i], parent1[i]);
64        }
65
66        if (ProblemInstance.GetDistance(
67          child[i] + 1, parent1[(i + 1) % child.Length] + 1)
68          <
69          ProblemInstance.GetDistance(
70          child[i] + 1, parent2[(i + 1) % child.Length] + 1)) {
71          child[(i + 1) % child.Length] = parent1[(i + 1) % child.Length];
72          Swap(parent2, parent2[(i + 1) % child.Length], parent1[(i + 1) % child.Length]);
73        } else {
74          child[(i + 1) % child.Length] = parent2[(i + 1) % child.Length];
75          Swap(parent1, parent1[(i + 1) % child.Length], parent2[(i + 1) % child.Length]);
76        }
77
78        i = (i + 1) % child.Length;
79      }
80
81      return child;
82    }
83  }
84}
Note: See TracBrowser for help on using the repository browser.