RNG.h

Go to the documentation of this file.

//Copyright (c) 2013-2014, The MercuryDPM Developers Team. All rights reserved.
//For the list of developers, see <http://www.MercuryDPM.org/Team>.
//
//Redistribution and use in source and binary forms, with or without
//modification, are permitted provided that the following conditions are met:
//  * Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//  * 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.
//  * Neither the name MercuryDPM nor the
//    names of its contributors may be used to endorse or promote products
//    derived from this software without specific prior written permission.
//
//THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE MERCURYDPM DEVELOPERS TEAM 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.

#ifndef RNG_H
#define RNG_H

//Used by the randomise function
#include <time.h>
#include <cmath>
#include <vector>
#include "ExtendedMath.h"

enum class RNGType : unsigned char
{
    LAGGED_FIBONACCI_GENERATOR=0,
    LINEAR_CONGRUENTIAL_GENERATOR=1
};

class RNG
{
public:
    RNG();
    
    void setRandomSeed(unsigned long int new_seed);
    
    void read(std::istream& is);

    void write(std::ostream& os) const;
    
    Mdouble getRandomNumber(Mdouble min, Mdouble max);

    Mdouble operator()(Mdouble min, Mdouble max)
    {
        return getRandomNumber(min, max);
    }

    Mdouble operator()()
    {
        return getRandomNumber(0.0, 1.0);
    }

    Mdouble test();

    void setLinearCongruentialGeneratorParmeters(unsigned const int a, unsigned const int c, unsigned const int m);
    
    void randomise();
    
    void setLaggedFibonacciGeneratorParameters(const unsigned int p, const unsigned int q);

    void setRandomNumberGenerator(RNGType type);
    
private:
    
    Mdouble getRandomNumberFromLinearCongruentialGenerator(Mdouble min, Mdouble max);

    Mdouble getRandomNumberFromLaggedFibonacciGenerator(Mdouble min, Mdouble max);

    void seedLaggedFibonacciGenerator();

    unsigned long int randomSeedLinearCongruentialGenerator_;

    std::vector<Mdouble> randomSeedLaggedFibonacciGenerator_;

    unsigned long int a_, c_, m_;

    unsigned long int p_, q_;

    RNGType type_;
    
};

#endif