Free cookie consent management tool by TermsFeed Policy Generator

source: branches/PersistenceSpeedUp/HeuristicLab.Problems.TravelingSalesman/3.3/Evaluators/TSPCoordinatesPathEvaluator.cs @ 12858

Last change on this file since 12858 was 5445, checked in by swagner, 14 years ago

Updated year of copyrights (#1406)

File size: 5.8 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2011 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.Common;
23using HeuristicLab.Core;
24using HeuristicLab.Data;
25using HeuristicLab.Encodings.PermutationEncoding;
26using HeuristicLab.Parameters;
27using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
28
29namespace HeuristicLab.Problems.TravelingSalesman {
30  /// <summary>
31  /// A base class for operators which evaluate TSP solutions given in path representation using city coordinates.
32  /// </summary>
33  [Item("TSPCoordinatesPathEvaluator", "A base class for operators which evaluate TSP solutions given in path representation using city coordinates.")]
34  [StorableClass]
35  public abstract class TSPCoordinatesPathEvaluator : TSPEvaluator, ITSPCoordinatesPathEvaluator {
36    private object locker = new object();
37
38    public ILookupParameter<Permutation> PermutationParameter {
39      get { return (ILookupParameter<Permutation>)Parameters["Permutation"]; }
40    }
41    public ILookupParameter<DoubleMatrix> CoordinatesParameter {
42      get { return (ILookupParameter<DoubleMatrix>)Parameters["Coordinates"]; }
43    }
44    public ILookupParameter<DistanceMatrix> DistanceMatrixParameter {
45      get { return (ILookupParameter<DistanceMatrix>)Parameters["DistanceMatrix"]; }
46    }
47    public ILookupParameter<BoolValue> UseDistanceMatrixParameter {
48      get { return (ILookupParameter<BoolValue>)Parameters["UseDistanceMatrix"]; }
49    }
50
51    [StorableConstructor]
52    protected TSPCoordinatesPathEvaluator(bool deserializing) : base(deserializing) { }
53    protected TSPCoordinatesPathEvaluator(TSPCoordinatesPathEvaluator original, Cloner cloner) : base(original, cloner) { }
54    protected TSPCoordinatesPathEvaluator()
55      : base() {
56      Parameters.Add(new LookupParameter<Permutation>("Permutation", "The TSP solution given in path representation which should be evaluated."));
57      Parameters.Add(new LookupParameter<DoubleMatrix>("Coordinates", "The x- and y-Coordinates of the cities."));
58      Parameters.Add(new LookupParameter<DistanceMatrix>("DistanceMatrix", "The matrix which contains the distances between the cities."));
59      Parameters.Add(new LookupParameter<BoolValue>("UseDistanceMatrix", "True if a distance matrix should be calculated and used for evaluation, otherwise false."));
60    }
61
62    [StorableHook(HookType.AfterDeserialization)]
63    private void AfterDeserialization() {
64      // BackwardsCompatibility3.3
65      #region Backwards compatible code (remove with 3.4)
66      LookupParameter<DoubleMatrix> oldDistanceMatrixParameter = Parameters["DistanceMatrix"] as LookupParameter<DoubleMatrix>;
67      if (oldDistanceMatrixParameter != null) {
68        Parameters.Remove(oldDistanceMatrixParameter);
69        Parameters.Add(new LookupParameter<DistanceMatrix>("DistanceMatrix", "The matrix which contains the distances between the cities."));
70        DistanceMatrixParameter.ActualName = oldDistanceMatrixParameter.ActualName;
71      }
72      #endregion
73    }
74
75    public sealed override IOperation Apply() {
76      if (UseDistanceMatrixParameter.ActualValue.Value) {
77        Permutation p = PermutationParameter.ActualValue;
78        DistanceMatrix dm = DistanceMatrixParameter.ActualValue;
79
80        if (dm == null) {  // calculate distance matrix
81          lock (locker) {
82            dm = DistanceMatrixParameter.ActualValue;
83            if (dm == null) {  // check again to avoid race condition
84              DoubleMatrix c = CoordinatesParameter.ActualValue;
85              dm = new DistanceMatrix(c.Rows, c.Rows);
86              for (int i = 0; i < dm.Rows; i++) {
87                for (int j = 0; j < dm.Columns; j++)
88                  dm[i, j] = CalculateDistance(c[i, 0], c[i, 1], c[j, 0], c[j, 1]);
89              }
90              DistanceMatrixParameter.ActualValue = (DistanceMatrix)dm.AsReadOnly();
91            }
92          }
93        }
94
95        double length = 0;
96        for (int i = 0; i < p.Length - 1; i++)
97          length += dm[p[i], p[i + 1]];
98        length += dm[p[p.Length - 1], p[0]];
99        QualityParameter.ActualValue = new DoubleValue(length);
100      } else {
101        Permutation p = PermutationParameter.ActualValue;
102        DoubleMatrix c = CoordinatesParameter.ActualValue;
103
104        double length = 0;
105        for (int i = 0; i < p.Length - 1; i++)
106          length += CalculateDistance(c[p[i], 0], c[p[i], 1], c[p[i + 1], 0], c[p[i + 1], 1]);
107        length += CalculateDistance(c[p[p.Length - 1], 0], c[p[p.Length - 1], 1], c[p[0], 0], c[p[0], 1]);
108        QualityParameter.ActualValue = new DoubleValue(length);
109      }
110      return base.Apply();
111    }
112
113    /// <summary>
114    /// Calculates the distance between two points.
115    /// </summary>
116    /// <param name="x1">The x-coordinate of point 1.</param>
117    /// <param name="y1">The y-coordinate of point 1.</param>
118    /// <param name="x2">The x-coordinate of point 2.</param>
119    /// <param name="y2">The y-coordinate of point 2.</param>
120    /// <returns>The calculated distance.</returns>
121    protected abstract double CalculateDistance(double x1, double y1, double x2, double y2);
122  }
123}
Note: See TracBrowser for help on using the repository browser.