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  public override string FunctionName { get { return "Beale"; } }


38  /// <summary>


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


40  /// </summary>


41  public override bool Maximization {


42  get { return false; }


43  }


44  /// <summary>


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


46  /// </summary>


47  public override double BestKnownQuality {


48  get { return 0; }


49  }


50  /// <summary>


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


52  /// </summary>


53  public override DoubleMatrix Bounds {


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


55  }


56  /// <summary>


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


58  /// </summary>


59  public override int MinimumProblemSize {


60  get { return 2; }


61  }


62  /// <summary>


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


64  /// </summary>


65  public override int MaximumProblemSize {


66  get { return 2; }


67  }


68 


69  [StorableConstructor]


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


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


72  public BealeEvaluator() : base() { }


73 


74  public override IDeepCloneable Clone(Cloner cloner) {


75  return new BealeEvaluator(this, cloner);


76  }


77 


78  public override RealVector GetBestKnownSolution(int dimension) {


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


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


81  }


82  /// <summary>


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


84  /// </summary>


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


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


87  public static double Apply(RealVector point) {


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


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


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


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


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


93  }


94 


95  /// <summary>


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


97  /// </summary>


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


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


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


101  public override double Evaluate(RealVector point) {


102  return Apply(point);


103  }


104  }


105  }

