pso_generational_racing.h

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#ifndef PAGMO_ALGORITHM_PSO_GENERATIONAL_RACING_H
#define PAGMO_ALGORITHM_PSO_GENERATIONAL_RACING_H

#include "../config.h"
#include "../serialization.h"
#include "base.h"
#include "../util/race_pop.h"
#include <limits>

namespace pagmo { namespace algorithm {


class __PAGMO_VISIBLE pso_generational_racing: public base
{
public:
        pso_generational_racing(int gen=1, double omega = 0.7298, double eta1 = 2.05, double eta2 = 2.05, double vcoeff = 0.5, int variant = 5, int neighb_type = 2, int neighb_param = 4, unsigned int nr_eval_per_x = 5, unsigned int max_fevals = std::numeric_limits<unsigned int>::max());
        base_ptr clone() const;
        void evolve(population &) const;
        std::string get_name() const;
protected:      
        std::string human_readable_extra() const;
private:
        decision_vector particle__get_best_neighbor( population::size_type pidx, std::vector< std::vector<int> > &neighb, const std::vector<decision_vector> &lbX, const std::vector<fitness_vector> &lbfit, const problem::base &prob) const;
        void initialize_topology__gbest( const population &pop, decision_vector &gbX, fitness_vector &gbfit, std::vector< std::vector<int> > &neighb ) const;
        void initialize_topology__lbest( std::vector< std::vector<int> > &neighb ) const;
        void initialize_topology__von( std::vector< std::vector<int> > &neighb ) const;
        void initialize_topology__adaptive_random( std::vector< std::vector<int> > &neighb ) const;

        // Handles the averaging of stochastic fitness
        void particle__average_fitness(const problem::base &, fitness_vector &, const decision_vector &) const;
        //void particle__average_fitness_set_best(const problem::base &, std::vector<fitness_vector &, const decision_vector &) const;
        void particle__average_fitness_set_best(const problem::base &base, std::vector<fitness_vector> &F, population::size_type& best_idx, fitness_vector& best_fit, const std::vector<decision_vector> &X) const;

        // Helper routines for racing related features
        decision_vector particle__racing_get_best_neighbor( population::size_type pidx, std::vector< std::vector<int> > &neighb, const std::vector<decision_vector> &lbX, util::racing::race_pop& ) const;
        void racing__construct_race_environment( util::racing::race_pop & race_structure, const problem::base& prob, const std::vector<decision_vector> &x_list1, const std::vector<decision_vector> &x_list2 ) const;
        std::pair<population::size_type, unsigned int> racing__race_for_winner( util::racing::race_pop &race_structure, int idx1, int idx2, unsigned int max_fevals) 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_omega);
                ar & const_cast<double &>(m_eta1);
                ar & const_cast<double &>(m_eta2);
                ar & const_cast<double &>(m_vcoeff);
                ar & const_cast<int &>(m_variant);
                ar & const_cast<int &>(m_neighb_type);
                ar & const_cast<int &>(m_neighb_param);
                ar & m_fevals;
                ar & const_cast<unsigned int&>(m_max_fevals);
        }
        // Number of generations
        const int m_gen;
        // Particle Inertia weight, or alternatively the constriction coefficient
        const double m_omega;
        // magnitude of the force, applied to the particle's velocity, in the direction of its previous best position
        const double m_eta1;
        // magnitude of the force, applied to the particle's velocity, in the direction of the best position in its neighborhood
        const double m_eta2;
        // Velocity coefficient: velocity values will range in [ - var_range * m_vcoeff, var_range * m_vcoeff ]
        const double m_vcoeff;
        // Velocity update formula
        const int m_variant;
        // Swarm topology
        const int m_neighb_type;
        // parameterization of the swarm topology
        const int m_neighb_param;
        // Parameter controlling how many times a stochastic objective function
        // will be called for averaging
        const unsigned int m_nr_eval_per_x;
        // Incurred objective function evaluation
        mutable unsigned int m_fevals;
        // Maximum allowable fevals before algo terminates
        const unsigned int m_max_fevals;
};

}} //namespaces

BOOST_CLASS_EXPORT_KEY(pagmo::algorithm::pso_generational_racing)

#endif // PAGMO_ALGORITHM_PSO_GENERATIONAL_RACING_H