prg.h

/* Evoplex <https://evoplex.org>
 * Copyright (C) 2016-present - Marcos Cardinot <marcos@cardinot.net>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef PRG_H
#define PRG_H

#include <random>

namespace evoplex {

class PRG
{
public:
    explicit PRG(unsigned int seed);

    inline unsigned int seed() const
    { return m_seed; }

    inline bool bernoulli(double p)
    { std::bernoulli_distribution b(p); return b(m_mteng); }

    inline bool bernoulli()
    { return m_bernoulli(m_mteng); }

    template <typename T>
    T uniform(T min, T max)
    { std::uniform_real_distribution<T> d(min, max); return d(m_mteng); }

    inline int uniform(int min, int max)
    { std::uniform_int_distribution<int> d(min, max); return d(m_mteng); }

    inline size_t uniform(size_t min, size_t max)
    { std::uniform_int_distribution<size_t> d(min, max); return d(m_mteng); }

    template <typename T>
    T uniform(T max)
    { std::uniform_real_distribution<T> d(0, max); return d(m_mteng); }

    inline int uniform(int max)
    { std::uniform_int_distribution<int> d(0, max); return d(m_mteng); }

    inline size_t uniform(size_t max)
    { std::uniform_int_distribution<size_t> d(0, max); return d(m_mteng); }

    inline double uniform()
    { return m_doubleZeroOne(m_mteng); }

    template <typename T>
    inline T uniform(std::uniform_real_distribution<T> d)
    { return d(m_mteng); }

    template <typename T>
    T uniform(std::uniform_int_distribution<T> d)
    { return d(m_mteng); }

private:
    const unsigned int m_seed;
    std::mt19937 m_mteng; 
    std::uniform_real_distribution<double> m_doubleZeroOne;
    std::bernoulli_distribution m_bernoulli;
};

} // evoplex
#endif // PRG_H