#region License Information /* HeuristicLab * Copyright (C) 2002-2012 Heuristic and Evolutionary Algorithms Laboratory (HEAL) * * This file is part of HeuristicLab. * * HeuristicLab is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * HeuristicLab is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with HeuristicLab. If not, see . */ #endregion using HeuristicLab.Common; using HeuristicLab.Core; using HeuristicLab.Data; using HeuristicLab.Encodings.PermutationEncoding; using HeuristicLab.Parameters; using HeuristicLab.Persistence.Default.CompositeSerializers.Storable; namespace HeuristicLab.Problems.TravelingSalesman { /// /// An operator to evaluate inversion moves (2-opt). /// [Item("TSPInversionMovePathEvaluator", "Evaluates an inversion move (2-opt) by summing up the length of all added edges and subtracting the length of all deleted edges.")] [StorableClass] public abstract class TSPInversionMovePathEvaluator : TSPPathMoveEvaluator, IPermutationInversionMoveOperator { public ILookupParameter InversionMoveParameter { get { return (ILookupParameter)Parameters["InversionMove"]; } } [StorableConstructor] protected TSPInversionMovePathEvaluator(bool deserializing) : base(deserializing) { } protected TSPInversionMovePathEvaluator(TSPInversionMovePathEvaluator original, Cloner cloner) : base(original, cloner) { } public TSPInversionMovePathEvaluator() : base() { Parameters.Add(new LookupParameter("InversionMove", "The move to evaluate.")); } protected override double EvaluateByCoordinates(Permutation permutation, DoubleMatrix coordinates) { InversionMove move = InversionMoveParameter.ActualValue; int edge1source = permutation.GetCircular(move.Index1 - 1); int edge1target = permutation[move.Index1]; int edge2source = permutation[move.Index2]; int edge2target = permutation.GetCircular(move.Index2 + 1); if (move.Index2 - move.Index1 >= permutation.Length - 2) return 0; double moveQuality = 0; // remove two edges moveQuality -= CalculateDistance(coordinates[edge1source, 0], coordinates[edge1source, 1], coordinates[edge1target, 0], coordinates[edge1target, 1]); moveQuality -= CalculateDistance(coordinates[edge2source, 0], coordinates[edge2source, 1], coordinates[edge2target, 0], coordinates[edge2target, 1]); // add two edges moveQuality += CalculateDistance(coordinates[edge1source, 0], coordinates[edge1source, 1], coordinates[edge2source, 0], coordinates[edge2source, 1]); moveQuality += CalculateDistance(coordinates[edge1target, 0], coordinates[edge1target, 1], coordinates[edge2target, 0], coordinates[edge2target, 1]); return moveQuality; } protected override double EvaluateByDistanceMatrix(Permutation permutation, DistanceMatrix distanceMatrix) { InversionMove move = InversionMoveParameter.ActualValue; int edge1source = permutation.GetCircular(move.Index1 - 1); int edge1target = permutation[move.Index1]; int edge2source = permutation[move.Index2]; int edge2target = permutation.GetCircular(move.Index2 + 1); if (move.Index2 - move.Index1 >= permutation.Length - 2) return 0; double moveQuality = 0; // remove two edges moveQuality -= distanceMatrix[edge1source, edge1target]; moveQuality -= distanceMatrix[edge2source, edge2target]; // add two edges moveQuality += distanceMatrix[edge1source, edge2source]; moveQuality += distanceMatrix[edge1target, edge2target]; return moveQuality; } } }