wfg.h

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 *   Copyright (C) 2004-2015 The PaGMO development team,                     *
 *   Advanced Concepts Team (ACT), European Space Agency (ESA)               *
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 *   act@esa.int                                                             *
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#ifndef PAGMO_UTIL_HV_ALGORITHM_WFG_H
#define PAGMO_UTIL_HV_ALGORITHM_WFG_H

#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <iterator>

#include "base.h"
#include "../hypervolume.h"

namespace pagmo { namespace util { namespace hv_algorithm {


class __PAGMO_VISIBLE wfg : public base
{
public:
        wfg(const unsigned int stop_dimension = 2);
        double compute(std::vector<fitness_vector> &, const fitness_vector &) const;
        std::vector<double> contributions(std::vector<fitness_vector> &, const fitness_vector &) const;
        void verify_before_compute(const std::vector<fitness_vector> &, const fitness_vector &) const;
        base_ptr clone() const;
        std::string get_name() const;

private:
        void limitset(const unsigned int, const unsigned int, const unsigned int) const;
        double exclusive_hv(const unsigned int, const unsigned int) const;
        double compute_hv(const unsigned int) const;

        bool cmp_points(double* a, double* b) const;

        void allocate_wfg_members(std::vector<fitness_vector> &, const fitness_vector &) const;
        void free_wfg_members() const;

        // Current slice depth
        mutable unsigned int m_current_slice;

        // Array of point sets for each recursive level.
        mutable double*** m_frames;

        // Maintains the number of points at given recursion level.
        mutable unsigned int* m_frames_size;

        // Keeps track of currently allocated number of frames.
        mutable unsigned int m_n_frames;

        // Copy of the reference point
        mutable double* m_refpoint;

        // Size of the original front
        mutable unsigned int m_max_points;

        // Size of the dimension
        mutable unsigned int m_max_dim;
        // Dimension at which WFG stops the slicing
        const unsigned int m_stop_dimension;

        friend class boost::serialization::access;
        template <class Archive>
        void serialize(Archive &ar, const unsigned int)
        {
                ar & boost::serialization::base_object<base>(*this);
                ar & const_cast<unsigned int &>(m_stop_dimension);
        }
};

} } }

BOOST_CLASS_EXPORT_KEY(pagmo::util::hv_algorithm::wfg)

#endif