1  #region License Information


2  /* HeuristicLab


3  * Copyright (C) 20022013 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 HeuristicLab.Common;


24  using HeuristicLab.Core;


25  using HeuristicLab.Data;


26  using HeuristicLab.Encodings.RealVectorEncoding;


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


28 


29  namespace HeuristicLab.Problems.TestFunctions {


30  /// <summary>


31  /// The Beale function is defined for 2 dimensions with an optimum of 0 at (3, 0.5).


32  /// It is implemented as described in Moré, J.J., Garbow, B., and Hillstrom, K. 1981. Testing unconstrained optimization software. ACM Transactions on Mathematical Software 7, pp. 136140, ACM.


33  /// </summary>


34  [Item("BealeEvaluator", "Evaluates the Beale function on a given point. The optimum of this function is 0 at (3,0.5). It is implemented as described in Moré, J.J., Garbow, B., and Hillstrom, K. 1981. Testing unconstrained optimization software. ACM Transactions on Mathematical Software 7, pp. 136140, ACM.")]


35  [StorableClass]


36  public class BealeEvaluator : SingleObjectiveTestFunctionProblemEvaluator {


37  /// <summary>


38  /// Returns false as the Beale function is a minimization problem.


39  /// </summary>


40  public override bool Maximization {


41  get { return false; }


42  }


43  /// <summary>


44  /// Gets the optimum function value (0).


45  /// </summary>


46  public override double BestKnownQuality {


47  get { return 0; }


48  }


49  /// <summary>


50  /// Gets the lower and upper bound of the function.


51  /// </summary>


52  public override DoubleMatrix Bounds {


53  get { return new DoubleMatrix(new double[,] { { 4.5, 4.5 } }); }


54  }


55  /// <summary>


56  /// Gets the minimum problem size (2).


57  /// </summary>


58  public override int MinimumProblemSize {


59  get { return 2; }


60  }


61  /// <summary>


62  /// Gets the maximum problem size (2).


63  /// </summary>


64  public override int MaximumProblemSize {


65  get { return 2; }


66  }


67 


68  [StorableConstructor]


69  protected BealeEvaluator(bool deserializing) : base(deserializing) { }


70  protected BealeEvaluator(BealeEvaluator original, Cloner cloner) : base(original, cloner) { }


71  public BealeEvaluator() : base() { }


72 


73  public override IDeepCloneable Clone(Cloner cloner) {


74  return new BealeEvaluator(this, cloner);


75  }


76 


77  public override RealVector GetBestKnownSolution(int dimension) {


78  if (dimension != 2) throw new ArgumentException(Name + ": This function is only defined for 2 dimensions.", "dimension");


79  return new RealVector(new double[] { 3, 0.5 });


80  }


81  /// <summary>


82  /// Evaluates the test function for a specific <paramref name="point"/>.


83  /// </summary>


84  /// <param name="point">Ndimensional point for which the test function should be evaluated.</param>


85  /// <returns>The result value of the Beale function at the given point.</returns>


86  public static double Apply(RealVector point) {


87  double x1 = point[0], x2 = point[1];


88  double f1 = 1.5  x1 * (1  x2);


89  double f2 = 2.25  x1 * (1  x2 * x2);


90  double f3 = 2.625  x1 * (1  x2 * x2 * x2);


91  return (f1 * f1) + (f2 * f2) + (f3 * f3);


92  }


93 


94  /// <summary>


95  /// Evaluates the test function for a specific <paramref name="point"/>.


96  /// </summary>


97  /// <remarks>Calls <see cref="Apply"/>.</remarks>


98  /// <param name="point">Ndimensional point for which the test function should be evaluated.</param>


99  /// <returns>The result value of the Beale function at the given point.</returns>


100  public override double Evaluate(RealVector point) {


101  return Apply(point);


102  }


103  }


104  }

