// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-

//-----------------------------------------------------------------------------
// moeoContributionMetric.h
// (c) OPAC Team (LIFL), Dolphin Project (INRIA), 2007
/*
    This library...

    Contact: paradiseo-help@lists.gforge.inria.fr, http://paradiseo.gforge.inria.fr
 */
//-----------------------------------------------------------------------------

#ifndef MOEOCONTRIBUTIONMETRIC_H_
#define MOEOCONTRIBUTIONMETRIC_H_

#include <comparator/moeoParetoObjectiveVectorComparator.h>
#include <metric/moeoMetric.h>

/**
 * The contribution metric evaluates the proportion of non-dominated solutions given by a Pareto set relatively to another Pareto set
 * (Meunier, Talbi, Reininger: 'A multiobjective genetic algorithm for radio network optimization', in Proc. of the 2000 Congress on Evolutionary Computation, IEEE Press, pp. 317-324)
 */
template < class ObjectiveVector >
class moeoContributionMetric : public moeoVectorVsVectorBinaryMetric < ObjectiveVector, double >
{
public:

    /**
     * Returns the contribution of the Pareto set '_set1' relatively to the Pareto set '_set2'
     * @param _set1 the first Pareto set
     * @param _set2 the second Pareto set
     */
    double operator()(const std::vector < ObjectiveVector > & _set1, const std::vector < ObjectiveVector > & _set2) {
        unsigned int c  = card_C(_set1, _set2);
        unsigned int w1 = card_W(_set1, _set2);
        unsigned int n1 = card_N(_set1, _set2);
        unsigned int w2 = card_W(_set2, _set1);
        unsigned int n2 = card_N(_set2, _set1);
        return (double) (c / 2.0 + w1 + n1) / (c + w1 + n1 + w2 + n2);
    }


private:

    /** Functor to compare two objective vectors according to Pareto dominance relation */
    moeoParetoObjectiveVectorComparator < ObjectiveVector > paretoComparator;
    
    
    /**
     * Returns the number of solutions both in '_set1' and '_set2'
     * @param _set1 the first Pareto set
     * @param _set2 the second Pareto set
     */
    unsigned int card_C (const std::vector < ObjectiveVector > & _set1, const std::vector < ObjectiveVector > & _set2) {
        unsigned int c=0;
        for (unsigned int i=0; i<_set1.size(); i++)
            for (unsigned int j=0; j<_set2.size(); j++)
                if (_set1[i] == _set2[j]) {
                    c++;
                    break;
                }
        return c;
    }


    /**
     * Returns the number of solutions in '_set1' dominating at least one solution of '_set2'
     * @param _set1 the first Pareto set
     * @param _set2 the second Pareto set
     */
    unsigned int card_W (const std::vector < ObjectiveVector > & _set1, const std::vector < ObjectiveVector > & _set2) {
        unsigned int w=0;
        for (unsigned int i=0; i<_set1.size(); i++)
            for (unsigned int j=0; j<_set2.size(); j++)
                if (paretoComparator(_set2[j], _set1[i]))
                {
                    w++;
                    break;
                }
        return w;
    }


    /**
     * Returns the number of solutions in '_set1' having no relation of dominance with those from '_set2'
     * @param _set1 the first Pareto set
     * @param _set2 the second Pareto set
     */
    unsigned int card_N (const std::vector < ObjectiveVector > & _set1, const std::vector < ObjectiveVector > & _set2) {
        unsigned int n=0;
        for (unsigned int i=0; i<_set1.size(); i++) {
            bool domin_rel = false;
            for (unsigned int j=0; j<_set2.size(); j++)
                if ( (paretoComparator(_set2[j], _set1[i])) || (paretoComparator(_set1[i], _set2[j])) )
                {
                    domin_rel = true;
                    break;
                }
            if (! domin_rel)
                n++;
        }
        return n;
    }

};

#endif /*MOEOCONTRIBUTIONMETRIC_H_*/