1  #region License Information


2  /* HeuristicLab


3  * Copyright (C) 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.Collections.Generic;


23  using System.Linq;


24  using HeuristicLab.Common;


25  using HeuristicLab.Core;


26  using HeuristicLab.Data;


27  using HeuristicLab.Optimization;


28  using HeuristicLab.Parameters;


29  using HEAL.Attic;


30 


31  namespace HeuristicLab.Algorithms.ParticleSwarmOptimization {


32  [Item("Random Distinct Topology Initializer", "Each particle is informed by exactly k+1 distinct other particles (including itself).")]


33  [StorableType("50A4DB555C5C4C0EA4386C7DE14EA8A6")]


34  public sealed class RandomTopologyInitializer : TopologyInitializer, IStochasticOperator {


35  #region Parameters


36  public ILookupParameter<IRandom> RandomParameter {


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


38  }


39  public IValueLookupParameter<IntValue> NrOfConnectionsParameter {


40  get { return (IValueLookupParameter<IntValue>)Parameters["NrOfConnections"]; }


41  }


42  #endregion


43 


44  #region Construction & Cloning


45  [StorableConstructor]


46  private RandomTopologyInitializer(StorableConstructorFlag _) : base(_) { }


47  private RandomTopologyInitializer(RandomTopologyInitializer original, Cloner cloner) : base(original, cloner) { }


48  public RandomTopologyInitializer() {


49  Parameters.Add(new LookupParameter<IRandom>("Random", "A random number generation."));


50  Parameters.Add(new ValueLookupParameter<IntValue>("NrOfConnections", "Nr of connected neighbors.", new IntValue(3)));


51  }


52 


53  public override IDeepCloneable Clone(Cloner cloner) {


54  return new RandomTopologyInitializer(this, cloner);


55  }


56  #endregion


57 


58  public override IOperation Apply() {


59  var random = RandomParameter.ActualValue;


60  var swarmSize = SwarmSizeParameter.ActualValue.Value;


61  var nrOfConnections = NrOfConnectionsParameter.ActualValue.Value;


62 


63  ItemArray<IntArray> neighbors = new ItemArray<IntArray>(swarmSize);


64  for (int i = 0; i < swarmSize; i++) {


65  var numbers = Enumerable.Range(0, swarmSize).ToList();


66  numbers.RemoveAt(i);


67  var selectedNumbers = new List<int>(nrOfConnections + 1);


68  selectedNumbers.Add(i);


69  for (int j = 0; j < nrOfConnections && numbers.Count > 0; j++) {


70  int index = random.Next(numbers.Count);


71  selectedNumbers.Add(numbers[index]);


72  numbers.RemoveAt(index);


73  }


74  neighbors[i] = new IntArray(selectedNumbers.ToArray());


75  }


76  NeighborsParameter.ActualValue = neighbors;


77  return base.Apply();


78  }


79  }


80  }

