Program Listing for File rng.hpp

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/************************************************************************************
* MIT License                                                                       *
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* Copyright (c) 2023 Dr. Daniel Alejandro Matoz Fernandez                           *
*                    Dr. Rastko Sknepnek, University of Dundee                      *
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#ifndef __rng_hpp__
#define __rng_hpp__


#include <random>
#include <memory>

class RNG
{
public:

  RNG(unsigned int seed) : m_generator(seed), m_uniform_distribution(0.0,1.0), m_normal_distribution(0.0,1.0) { }

  ~RNG() { }

  real drnd()
  {
    return m_uniform_distribution(m_generator);
  }

  real gauss_rng(real sigma=1.0, real mu = 0.0)
  {
    return (m_normal_distribution(m_generator)*sigma + mu);
  }

  int lrnd(int N)
  {
    return static_cast<int>(N*drnd());
  }

private:

  std::mt19937_64 m_generator;
  std::uniform_real_distribution<real> m_uniform_distribution;  // Uniform random numbers
  std::normal_distribution<real> m_normal_distribution; // Gaussian distribution zero mean, unit variance

};


typedef std::unique_ptr<RNG> RNG_ptr;

#endif