erdos_renyi.cpp

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 *   Copyright (C) 2004-2015 The PaGMO development team,                     *
 *   Advanced Concepts Team (ACT), European Space Agency (ESA)               *
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#include <sstream>
#include <string>

#include "../exceptions.h"
#include "../rng.h"
#include "base.h"
#include "erdos_renyi.h"

namespace pagmo { namespace topology {


erdos_renyi::erdos_renyi(const double &prob):base(),m_prob(prob),m_drng(rng_generator::get<rng_double>())
{
        if (prob < 0 || prob > 1) {
                pagmo_throw(value_error,"probability must be in the [0,1] range");
        }
}

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

void erdos_renyi::connect(const vertices_size_type &n)
{
        for (std::pair<v_iterator,v_iterator> vertices = get_vertices(); vertices.first != vertices.second; ++vertices.first) {
                // Connect n bidirectionally to the other nodes with probability m_prob. Also, avoid to connect n with itself.
                if (*vertices.first != n && m_drng() < m_prob) {
                        add_edge(n,*vertices.first);
                        add_edge(*vertices.first,n);
                }
        }
}

std::string erdos_renyi::human_readable_extra() const
{
        std::ostringstream oss;
        oss << "\tprobability: " << m_prob << '\n';
        return oss.str();
}

std::string erdos_renyi::get_name() const
{
        return "Erdos-Renyi";
}

}} //namespaces

BOOST_CLASS_EXPORT_IMPLEMENT(pagmo::topology::erdos_renyi)