roulette.h

/*
    Evocosm is a C++ framework for implementing evolutionary algorithms.

    Copyright 2011 Scott Robert Ladd. All rights reserved.

    Evocosm is user-supported open source software. Its continued development is dependent
    on financial support from the community. You can provide funding by visiting the Evocosm
    website at:

        http://www.coyotegulch.com

    You may license Evocosm in one of two fashions:

    1) Simplified BSD License (FreeBSD License)

    Redistribution and use in source and binary forms, with or without modification, are
    permitted provided that the following conditions are met:

    1.  Redistributions of source code must retain the above copyright notice, this list of
        conditions and the following disclaimer.

    2.  Redistributions in binary form must reproduce the above copyright notice, this list
        of conditions and the following disclaimer in the documentation and/or other materials
        provided with the distribution.

    THIS SOFTWARE IS PROVIDED BY SCOTT ROBERT LADD ``AS IS'' AND ANY EXPRESS OR IMPLIED
    WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
    FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SCOTT ROBERT LADD OR
    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
    ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
    ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    The views and conclusions contained in the software and documentation are those of the
    authors and should not be interpreted as representing official policies, either expressed
    or implied, of Scott Robert Ladd.

    2) Closed-Source Proprietary License

    If your project is a closed-source or proprietary project, the Simplified BSD License may
    not be appropriate or desirable. In such cases, contact the Evocosm copyright holder to
    arrange your purchase of an appropriate license.

    The author can be contacted at:

          scott.ladd@coyotegulch.com
          scott.ladd@gmail.com
          http:www.coyotegulch.com
*/

#if !defined(LIBEVOCOSM_ROULETTE_H)
#define LIBEVOCOSM_ROULETTE_H

// standard C++ Library
#include <cmath>
#include <vector>
#include <limits>

// libevocosm
#include "evocommon.h"

namespace libevocosm
{
    using std::vector;


    class roulette_wheel : protected globals
    {
    public:

        roulette_wheel(const vector<double> & a_weights,
                       double a_min_weight = std::numeric_limits<double>::epsilon(),
                       double a_max_weight = std::numeric_limits<double>::max());


        roulette_wheel(const double * a_weights,
                       size_t a_length,
                       double a_min_weight = std::numeric_limits<double>::epsilon(),
                       double a_max_weight = std::numeric_limits<double>::max());


        roulette_wheel(const roulette_wheel & a_source);


        roulette_wheel & operator = (const roulette_wheel & a_source);


        ~roulette_wheel();


        size_t get_size() const
        {
            return m_size;
        }


        double set_weight(size_t a_index, double a_weight);


        double get_weight(size_t a_index) const;


        size_t get_index() const;

    protected:
        size_t m_size;

        double * m_weights;

        double m_total_weight;

        double m_min_weight;

        double m_max_weight;

    private:
        // internal copy function
        void copy(const roulette_wheel & a_source);
    };
};

#endif