source: branches/VRP/HeuristicLab.Problems.VehicleRouting/3.4/Encodings/Alba/Creators/RandomCreator.cs @ 7543

Last change on this file since 7543 was 7543, checked in by svonolfe, 8 years ago

Fixed minor issues (#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 System;
23using System.Collections.Generic;
24using HeuristicLab.Core;
25using HeuristicLab.Data;
26using HeuristicLab.Encodings.PermutationEncoding;
27using HeuristicLab.Optimization;
28using HeuristicLab.Parameters;
29using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
30using HeuristicLab.Common;
31
32namespace HeuristicLab.Problems.VehicleRouting.Encodings.Alba {
33  [Item("RandomCreator", "Creates a randomly initialized VRP solution.")]
34  [StorableClass]
35  public sealed class RandomCreator : DefaultRepresentationCreator, IStochasticOperator {
36    #region IStochasticOperator Members
37    public ILookupParameter<IRandom> RandomParameter {
38      get { return (LookupParameter<IRandom>)Parameters["Random"]; }
39    }
40    #endregion
41
42    [StorableConstructor]
43    private RandomCreator(bool deserializing) : base(deserializing) { }
44
45    public RandomCreator()
46      : base() {
47      Parameters.Add(new LookupParameter<IRandom>("Random", "The pseudo random number generator."));
48    }
49
50    public override IDeepCloneable Clone(Cloner cloner) {
51      return new RandomCreator(this, cloner);
52    }
53
54    private RandomCreator(RandomCreator original, Cloner cloner)
55      : base(original, cloner) {
56    }
57
58    protected override List<int> CreateSolution() {
59      int cities = ProblemInstance.Cities.Value;
60      int vehicles = ProblemInstance.Vehicles.Value;
61
62      int[] perm = new int[cities + vehicles];
63      int[] sortingArray = new int[perm.Length - 2];
64      for (int i = 0; i < cities; i++)
65        perm[i] = i + 1;
66      for (int i = cities; i < cities + vehicles; i++)
67        perm[i] = -(i - cities);
68      for (int i = 0; i < perm.Length - 2; i++) {
69        sortingArray[i] = RandomParameter.ActualValue.Next(perm.Length * 2);
70      }
71      // shuffle perm from 1...n-1 by sorting sortingArray (perm[0] and perm[n] must stay 0)
72      bool done;
73      do {
74        done = true;
75        for (int i = 0; i < perm.Length - 3; i++) {
76          if (sortingArray[i] > sortingArray[i + 1]) {
77            int h = sortingArray[i];
78            sortingArray[i] = sortingArray[i + 1];
79            sortingArray[i + 1] = h;
80            h = perm[i + 1];
81            perm[i + 1] = perm[i + 2];
82            perm[i + 2] = h;
83            done = false;
84          }
85        }
86      } while (!done);
87
88      return new List<int>(perm);
89    }
90  }
91}
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