indicator.cpp

#include "indicator.h"

/**
 * Returns the associated espsilon-indicator. In the complete algorithm, we only
 * need to take as arguments an only vector, but we still use here A and B as
 * sets of vectors. Furthermore, instead of calling in every
 * epsilon_indicator the method coco_evaluate, we better save every f(x) and
 * enter as parameters of the function the two vectors f(x1) and f(x2) we want
 * to compare.
 * @param fa: image of the first vector to compare by f
 * @param fb: image of the second vector to compare by f
 * @returns: the espsilon-indicator
 */
double epsilon_indicator(double [][] a, double [][] b, int dim_obj = a[0], int dim_a = 1, int dim_b = 1) {
      int  i, j, k;
      double  eps = 0.0, eps_j = 0.0, eps_k=0.0, eps_temp;

      /* Here we search for the value of
       * I (A, B) =
       *   min{eps} (∀x2 ∈ B ∃x1 ∈ A : fi(x1) − eps ≤ fi(x2) for i ∈ {1,...,n}).
       * eps is between 0 and the dimension of the vectors
       *
       */
      for (i = 0; i < dim_a; i++) {
        for (j = 0; j < dim_b; j++) {
          for (k = 0; k < dim_obj; k++) {
            eps_temp = b[j][k] - a[i][k];
            if (k == 0)
              eps_k = eps_temp;
            else if (eps_k < eps_temp)
              eps_k = eps_temp;
          }
          if (j == 0)
            eps_j = eps_k;
          else if (eps_j > eps_k)
            eps_j = eps_k;
        }
        if (i == 0)
          eps = eps_j;
        else if (eps < eps_j)
          eps = eps_j;
      }
      return eps;
    }
}