sga.h

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#ifndef PAGMO_ALGORITHM_SGA_H
#define PAGMO_ALGORITHM_SGA_H

#include "../config.h"
#include "../problem/base.h"
#include "../serialization.h"
#include "base.h"

namespace pagmo { namespace algorithm {


class __PAGMO_VISIBLE sga: public base
{
public:
        struct selection {
                enum type {BEST20 = 0,ROULETTE = 1};
        };
        struct mutation {
                        enum type {GAUSSIAN = 0, RANDOM = 1};

                        mutation(mutation::type t, double width) : m_type(t),m_width(width) {}
                        type m_type;
                        double m_width;
                private:
                        friend class boost::serialization::access;
                        template <class Archive>
                        void serialize(Archive &ar, const unsigned int)
                        {
                                ar & m_type;
                                ar & m_width;
                        }
        };

        struct crossover {
                enum type {BINOMIAL = 0, EXPONENTIAL = 1};
        };
        sga(int gen  = 1, const double &cr = .95, const double &m = .02, int elitism = 1,
            mutation::type mut  = mutation::GAUSSIAN, double width = 0.1,
            selection::type sel = selection::ROULETTE,
            crossover::type cro = crossover::EXPONENTIAL);
        base_ptr clone() const;
        void evolve(population &) const;
        std::string get_name() const;
protected:
        std::string human_readable_extra() const;
private:
        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<int &>(m_gen);
                ar & const_cast<double &>(m_cr);
                ar & const_cast<double &>(m_m);
                ar & const_cast<int &>(m_elitism);
                ar & const_cast<mutation &>(m_mut);
                ar & const_cast<selection::type &>(m_sel);
                ar & const_cast<crossover::type &>(m_cro);
        }  
        //Number of generations
        const int m_gen;
        //Crossover rate
        const double m_cr;
        //Mutation rate
        const double m_m;

        //Elitism (number of generations after which to reinsert the best)
        const int m_elitism;
        //Mutation
        const mutation m_mut;
        //Selection_type
        const selection::type m_sel;
        //Crossover_type
        const crossover::type m_cro;
};

}} //namespaces

BOOST_CLASS_EXPORT_KEY(pagmo::algorithm::sga)

#endif // PAGMO_ALGORITHM_SGA_H