pol.cpp

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#include <boost/math/constants/constants.hpp>
#include <cmath>

#include "../exceptions.h"
#include "../types.h"
#include "base.h"
#include "pol.h"

namespace pagmo { namespace problem {

pol::pol():base(2,0,2)
{
        // Set bounds.
        set_lb(-std::atan(1.0f) * 4.0f); //-PI
        set_ub(std::atan(1.0f) * 4.0f); //PI
}

base_ptr pol::clone() const
{
        return base_ptr(new pol(*this));
}

void pol::objfun_impl(fitness_vector &f, const decision_vector &x) const
{
        pagmo_assert(f.size() == 2);
        pagmo_assert(x.size() == 2);

        f[0] = 0;
        f[1] = 0;

        double a1 = 0.5 * sin(1.0) - 2 * cos(1.0) + sin(2.0) - 1.5 * cos(2.0);
 
        double a2 = 1.5 * sin(1.0) - cos(1.0) + 2 * sin(2.0) - 0.5 * cos(2.0);
 
        double b1 = 0.5 * sin(x[0]) - 2 * cos(x[0]) + sin(x[1]) - 1.5 * cos(x[1]);
 
        double b2 = 1.5 * sin(x[0]) - cos(x[0]) + 2 * sin(x[1]) - 0.5 * cos(x[1]);

        f[0] = 1 + (a1-b1)*(a1-b1) + (a2-b2)*(a2-b2);
        f[1] = (x[0]+3)*(x[0]+3) + (x[1]+1)*(x[1]+1);
}

std::string pol::get_name() const
{
        return "Poloni's study";
}


}} //namespaces

BOOST_CLASS_EXPORT_IMPLEMENT(pagmo::problem::pol)