dominance.c

/* Domination checking routines */

# include <stdio.h>
# include <stdlib.h>
# include <math.h>

# include "nsga2.h"
# include "rand.h"

/* Routine for usual non-domination checking
   It will return the following values
   1 if a dominates b
   -1 if b dominates a
   0 if both a and b are non-dominated */

int check_dominance (NSGA2Type *nsga2Params, individual *a, individual *b)
{
    int i;
    int flag1;
    int flag2;
    flag1 = 0;
    flag2 = 0;
    if (a->constr_violation<0 && b->constr_violation<0)
    {
        if (a->constr_violation > b->constr_violation)
        {
            return (1);
        }
        else
        {
            if (a->constr_violation < b->constr_violation)
            {
                return (-1);
            }
            else
            {
                return (0);
            }
        }
    }
    else
    {
        if (a->constr_violation < 0 && b->constr_violation == 0)
        {
            return (-1);
        }
        else
        {
            if (a->constr_violation == 0 && b->constr_violation <0)
            {
                return (1);
            }
            else
            {
                for (i=0; i<nsga2Params->nobj; i++)
                {
                    if (a->obj[i] < b->obj[i])
                    {
                        flag1 = 1;

                    }
                    else
                    {
                        if (a->obj[i] > b->obj[i])
                        {
                            flag2 = 1;
                        }
                    }
                }
                if (flag1==1 && flag2==0)
                {
                    return (1);
                }
                else
                {
                    if (flag1==0 && flag2==1)
                    {
                        return (-1);
                    }
                    else
                    {
                        return (0);
                    }
                }
            }
        }
    }
}