source: branches/HeuristicLab.Problems.MultiObjectiveTestFunctions/HeuristicLab.Problems.MultiObjectiveTestFunctions/3.3/Testfunctions/DTLZ/DTLZ6.cs @ 13620

using System;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Encodings.RealVectorEncoding;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Problems.MultiObjectiveTestFunctions {
  [Item("DTLZ6", "Testfunction as defined as DTLZ5 in http://repository.ias.ac.in/81671/ [30.11.15]")]
  [StorableClass]
  public class DTLZ6 : DTLZ {

    [StorableConstructor]
    protected DTLZ6(bool deserializing) : base(deserializing) { }
    protected DTLZ6(DTLZ6 original, Cloner cloner) : base(original, cloner) { }
    public override IDeepCloneable Clone(Cloner cloner) {
      return new DTLZ6(this, cloner);
    }
    public DTLZ6() : base() { }

    public override double[] Evaluate(RealVector r, int objectives) {
      if (r.Length < objectives) {
        throw new Exception("The dimensionality of the problem(ProblemSize) must be larger than the dimensionality of the solution(SolutionSize) ");
      }
      double[] res = new double[objectives];

      //calculate g(Xm)
      double g = 0;
      for (int i = objectives; i < r.Length; i++) {
        g += Math.Pow(r[i], 0.1);
      }

      //phi definition
      Func<double, double> phi;
      phi = (double x) => { return Math.PI / (4 * (1 + g)) * (1 + 2 * g * x); };

      //calculating f0...fM-1
      for (int i = 0; i < objectives; i++) {
        double f = i == 0 ? 1 : (Math.Sin(phi(r[objectives - i - 1]) * Math.PI / 2)) * (1 + g);
        for (int j = 0; j < objectives - i - 1; j++) {
          f *= Math.Cos(phi(r[j]) * Math.PI / 2);
        }
        res[i] = f;
      }
      return res;
    }
  }
}