1  #region License Information


2  /* HeuristicLab


3  * Copyright (C) 20022018 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 


22  using System;


23  using System.Collections.Generic;


24  using System.Linq;


25  using HeuristicLab.Common;


26  using HeuristicLab.Core;


27  using HeuristicLab.Data;


28  using HeuristicLab.Encodings.IntegerVectorEncoding;


29  using HeuristicLab.Optimization;


30  using HeuristicLab.Parameters;


31  using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;


32  using HeuristicLab.Random;


33 


34  namespace HeuristicLab.Problems.GeneralizedQuadraticAssignment {


35  [Item("Stochastic NMove SingleMoveGenerator", "Randomly samples a single NMove.")]


36  [StorableClass]


37  public class StochasticNMoveSingleMoveGenerator : GQAPNMoveGenerator, IStochasticOperator, ISingleMoveGenerator {


38 


39  public ILookupParameter<IRandom> RandomParameter {


40  get { return (ILookupParameter<IRandom>)Parameters["Random"]; }


41  }


42 


43  [StorableConstructor]


44  protected StochasticNMoveSingleMoveGenerator(bool deserializing) : base(deserializing) { }


45  protected StochasticNMoveSingleMoveGenerator(StochasticNMoveSingleMoveGenerator original, Cloner cloner) : base(original, cloner) { }


46  public StochasticNMoveSingleMoveGenerator()


47  : base() {


48  Parameters.Add(new LookupParameter<IRandom>("Random", "The random number generator that should be used."));


49  }


50 


51  public override IDeepCloneable Clone(Cloner cloner) {


52  return new StochasticNMoveSingleMoveGenerator(this, cloner);


53  }


54 


55  public static NMove GenerateUpToN(IRandom random, IntegerVector assignment, int n, DoubleArray capacities) {


56  return GenerateExactlyN(random, assignment, random.Next(n) + 1, capacities);


57  }


58 


59  public static NMove GenerateOneMove(IRandom random, IntegerVector assignment, DoubleArray capacities) {


60  var locations = capacities.Length;


61  if (locations <= 1) throw new ArgumentException("There must be at least two locations.");


62  var dim = assignment.Length;


63  var equip = random.Next(dim);


64  var equipments = new List<int>(1) { equip };


65 


66  var reassignment = new int[dim];


67  reassignment[equip] = 1 + (assignment[equip] + random.Next(1, locations)) % locations;


68 


69  return new NMove(reassignment, equipments);


70  }


71 


72  public static NMove GenerateTwoMove(IRandom random, IntegerVector assignment, DoubleArray capacities) {


73  var locations = capacities.Length;


74  if (locations <= 1) throw new ArgumentException("There must be at least two locations.");


75  var dim = assignment.Length;


76  var equipments = new List<int>(2) { random.Next(dim) };


77  equipments.Add((equipments[0] + random.Next(1, dim)) % dim);


78 


79  var reassignment = new int[dim];


80  for (var i = 0; i < 2; i++) {


81  var equip = equipments[i];


82  reassignment[equip] = 1 + (assignment[equip] + random.Next(1, locations)) % locations;


83  }


84  return new NMove(reassignment, equipments);


85  }


86 


87  public static NMove GenerateExactlyN(IRandom random, IntegerVector assignment, int n, DoubleArray capacities) {


88  if (n == 1) return GenerateOneMove(random, assignment, capacities);


89  if (n == 2) return GenerateTwoMove(random, assignment, capacities);


90  var locations = capacities.Length;


91  if (locations <= 1) throw new ArgumentException("There must be at least two locations.");


92  var dim = assignment.Length;


93  var equipments = Enumerable.Range(0, dim).SampleRandomWithoutRepetition(random, n, dim).ToList();


94 


95  var reassignment = new int[dim];


96  for (var i = 0; i < n; i++) {


97  var equip = equipments[i];


98  reassignment[equip] = 1 + (assignment[equip] + random.Next(1, locations)) % locations;


99  }


100  return new NMove(reassignment, equipments);


101  }


102 


103  public override IEnumerable<NMove> GenerateMoves(IntegerVector assignment, int n, GQAPInstance problemInstance) {


104  yield return GenerateUpToN(RandomParameter.ActualValue, assignment, n, problemInstance.Capacities);


105  }


106  }


107  }

