spheres.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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#ifndef PAGMO_SPHERES_H
#define PAGMO_SPHERES_H

#include <string>
#include <vector>
#include <gsl/gsl_odeiv2.h>

#include "../config.h"
#include "../serialization.h"
#include "../types.h"
#include "base_stochastic.h"
#include "../rng.h"

namespace pagmo { namespace problem {


class __PAGMO_VISIBLE spheres: public base_stochastic
{
        static int ode_func( double t, const double y[], double f[], void *params );
        public:

                spheres(int n_evaluations = 10, int n_hidden = 10, double ode_prec = 1E-6, unsigned int seed = 0, bool symmetric = false, double sim_time = 50.0, const std::vector<double>& sides = std::vector<double>(3,0.5));


                spheres(const spheres &);


                ~spheres();


                std::vector<std::vector<double> > post_evaluate(const decision_vector &x, int N = 25000, unsigned int seed = 0) const;


                std::vector<std::vector<double> > simulate(const decision_vector & x, const std::vector<double> &ic, int N) const;
                std::string get_name() const;
                base_ptr clone() const;
                
                std::vector<double> get_nn_weights(decision_vector x) const;

        protected:
                void objfun_impl(fitness_vector &, const decision_vector &) const;
                std::string human_readable_extra() const;
        private:
                // Class representing a feed forward neural network
                class ffnn {
                                friend class spheres;
                        public:
                                ffnn(const unsigned int, const unsigned int,const unsigned int);
                                void eval(double[], const double[]) const;
                                void set_weights(const std::vector<double> &);
                        private:
                                friend class boost::serialization::access;
                                template <class Archive>
                                void serialize(Archive &ar, const unsigned int)
                                {
                                        ar & const_cast<unsigned int &>(m_n_inputs);
                                        ar & const_cast<unsigned int &>(m_n_hidden);
                                        ar & const_cast<unsigned int &>(m_n_outputs);
                                        ar & m_weights;
                                        ar & m_hidden;
                                }
                                const unsigned int m_n_inputs;
                                const unsigned int m_n_hidden;
                                const unsigned int m_n_outputs;
                                std::vector<double> m_weights;
                                mutable std::vector<double> m_hidden;
                };
                void set_nn_weights(const decision_vector& x) const;
                double single_fitness( const std::vector<double> &, const ffnn& ) const;
                friend class boost::serialization::access;
                template <class Archive>
                void serialize(Archive &ar, const unsigned int)
                {
                        ar & boost::serialization::base_object<base_stochastic>(*this);
                        ar & m_ffnn;
                        ar & m_n_evaluations;
                        ar & m_n_hidden_neurons;
                        ar & const_cast<double &>(m_numerical_precision);
                        ar & m_ic;
                        ar & m_symm;
                        ar & m_sim_time;
                        ar & m_sides;
                }
                gsl_odeiv2_driver*                              m_gsl_drv_pntr;
                gsl_odeiv2_system                               m_sys;
                mutable ffnn                                    m_ffnn;
                int                                                             m_n_evaluations;
                int                                                             m_n_hidden_neurons;
                const double                                    m_numerical_precision;
                mutable std::vector<double>             m_ic;   
                bool                                                    m_symm;
                double                                                  m_sim_time;
                std::vector<double>                             m_sides;
};

}} //namespaces

BOOST_CLASS_EXPORT_KEY(pagmo::problem::spheres)
#endif // PAGMO_SPHERES_H