rastrigin.cpp

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

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

namespace pagmo { namespace problem {


rastrigin::rastrigin(int n):base(n)
{
        // Set bounds.
        set_lb(-5.12);
        set_ub(5.12);
}

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

void rastrigin::objfun_impl(fitness_vector &f, const decision_vector &x) const
{
        pagmo_assert(f.size() == 1);
        const double omega = 2.0 * boost::math::constants::pi<double>();
        f[0] = 0;
        const decision_vector::size_type n = x.size();
        for (decision_vector::size_type i = 0; i < n; ++i) {
                f[0] += x[i] * x[i] - 10.0 * std::cos(omega * x[i]);
        }
        f[0] += 10.0 * n;
}

std::string rastrigin::get_name() const
{
        return "Rastrigin";
}

}}

BOOST_CLASS_EXPORT_IMPLEMENT(pagmo::problem::rastrigin)