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.Data;


26 


27  namespace HeuristicLab.Algorithms.ALPS {


28  /// <summary>


29  /// Defines the growth of age limits for the layers.


30  /// </summary>


31  public enum AgingScheme {


32  Linear,


33  Fibonacci,


34  Polynomial,


35  Exponential


36  }


37 


38  /// <summary>


39  /// Helper for calculating the age limits for a AgingScheme and a given AgeGap.


40  /// </summary>


41  public static class AgingSchemeCalculator {


42  public static IntArray CalculateAgeLimits(this AgingScheme scheme, int ageGap, int numberOfLayers) {


43  IEnumerable<int> schemeGenerator;


44  switch (scheme) {


45  case AgingScheme.Linear: schemeGenerator = LinearAgingScheme(); break;


46  case AgingScheme.Fibonacci: schemeGenerator = FibonacciAgingScheme(); break;


47  case AgingScheme.Polynomial: schemeGenerator = PolynomialAgingScheme(2); break;


48  case AgingScheme.Exponential: schemeGenerator = ExponentialAgingScheme(2); break;


49  default: throw new NotSupportedException("Aging Scheme " + scheme + " is not supported.");


50  }


51 


52  return new IntArray(schemeGenerator.Select(a => a * ageGap).Take(numberOfLayers).ToArray());


53  }


54 


55  #region Scheme definitions


56  // 1 2 3 4 5 6 7 ...


57  private static IEnumerable<int> LinearAgingScheme() {


58  for (int i = 0; ; i++)


59  yield return i + 1;


60  }


61  // 1 2 3 5 8 13 21 ...


62  private static IEnumerable<int> FibonacciAgingScheme() {


63  for (int i = 1, next = 2, temp; ; temp = next, next = i + next, i = temp)


64  yield return i;


65  }


66  // (n^2): 1 2 4 9 16 25 36 ...


67  private static IEnumerable<int> PolynomialAgingScheme(double exp) {


68  yield return 1;


69  yield return 2;


70  for (int i = 2; ; i++)


71  yield return (int)Math.Pow(i, exp);


72  }


73  // 1 2 4 8 16 32 64 ...


74  private static IEnumerable<int> ExponentialAgingScheme(double @base) {


75  for (int i = 0; ; i++)


76  yield return (int)Math.Pow(@base, i);


77  }


78  #endregion


79  }


80  } 
