#region License Information /* HeuristicLab * Copyright (C) 2002-2015 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 System; using HeuristicLab.Common; using HeuristicLab.Core; using HeuristicLab.Encodings.PermutationEncoding; using HeuristicLab.Optimization; using HeuristicLab.Parameters; using HeuristicLab.Persistence.Default.CompositeSerializers.Storable; namespace HeuristicLab.Problems.PTSP { [Item("Stochastic 2.5-SingleMoveGenerator", "Randomly samples a single from all possible inversion and shift moves (2.5-opt) from a given permutation.")] [StorableClass] public sealed class StochasticTwoPointFiveSingleMoveGenerator : TwoPointFiveMoveGenerator, IStochasticOperator, ISingleMoveGenerator { public ILookupParameter RandomParameter { get { return (ILookupParameter)Parameters["Random"]; } } [StorableConstructor] private StochasticTwoPointFiveSingleMoveGenerator(bool deserializing) : base(deserializing) { } private StochasticTwoPointFiveSingleMoveGenerator(StochasticTwoPointFiveSingleMoveGenerator original, Cloner cloner) : base(original, cloner) { } public StochasticTwoPointFiveSingleMoveGenerator() : base() { Parameters.Add(new LookupParameter("Random", "The random number generator.")); } public override IDeepCloneable Clone(Cloner cloner) { return new StochasticTwoPointFiveSingleMoveGenerator(this, cloner); } public static TwoPointFiveMove Apply(Permutation permutation, IRandom random) { int length = permutation.Length; if (length == 1) throw new ArgumentException("Stochastic 2.5-SingleMoveGenerator: There cannot be an inversion move given a permutation of length 1.", "permutation"); int index1 = random.Next(length - 1); int index2 = random.Next(index1 + 1, length); if (permutation.PermutationType == PermutationTypes.RelativeUndirected) { if (length > 3) { while (index2 - index1 >= length - 2) index2 = random.Next(index1 + 1, length); } } bool isInvert = random.NextDouble() > 0.5; return new TwoPointFiveMove(index1, index2, isInvert); } protected override TwoPointFiveMove[] GenerateMoves(Permutation permutation) { return new[] { Apply(permutation, RandomParameter.ActualValue) }; } } }