#region License Information /* HeuristicLab * Copyright (C) 2002-2016 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.Persistence.Default.CompositeSerializers.Storable; namespace HeuristicLab.Encodings.PermutationEncoding { /// /// Manipulates a permutation array by swaping three randomly chosen elements. /// /// /// It is implemented such that first 3 positions are randomly chosen in the interval [0;N) with N = length of the permutation with all positions being distinct from each other. /// Then position 1 is put in place of position 3, position 2 is put in place of position 1 and position 3 is put in place of position 2. /// [Item("Swap3Manipulator", "An operator which manipulates a permutation array by swaping three randomly chosen elements. It is implemented such that first 3 positions are randomly chosen in the interval [0;N) with N = length of the permutation with all positions being distinct from each other. Then position 1 is put in place of position 3, position 2 is put in place of position 1 and position 3 is put in place of position 2.")] [StorableClass] public class Swap3Manipulator : PermutationManipulator { [StorableConstructor] protected Swap3Manipulator(bool deserializing) : base(deserializing) { } protected Swap3Manipulator(Swap3Manipulator original, Cloner cloner) : base(original, cloner) { } public Swap3Manipulator() : base() { } public override IDeepCloneable Clone(Cloner cloner) { return new Swap3Manipulator(this, cloner); } /// /// Swaps three randomly chosen elements of the given array. /// /// Thrown when the contains less than 3 elements. /// /// It is implemented such that first 3 positions are randomly chosen in the interval [0;N) with N = length of the permutation with all positions being distinct from each other. /// Then position 1 is put in place of position 3, position 2 is put in place of position 1 and position 3 is put in place of position 2. /// /// The random number generator. /// The permutation to manipulate. public static void Apply(IRandom random, Permutation permutation) { if (permutation.Length < 3) throw new ArgumentException("Swap3Manipulator: The permutation must be at least of size 3.", "permutation"); int index1, index2, index3; do { index1 = random.Next(permutation.Length); index2 = random.Next(permutation.Length); index3 = random.Next(permutation.Length); } while (index1 == index2 || index2 == index3 || index1 == index3); permutation.Swap(index1, index2); permutation.Swap(index2, index3); } /// /// Swaps three randomly chosen elements of the given array. /// /// Calls . /// A random number generator. /// The permutation to manipulate. protected override void Manipulate(IRandom random, Permutation permutation) { Apply(random, permutation); } } }