(C++) (Boost C++ library) random

How to: get a random number from a normal distribution?

include <boost/random/normal_distribution.hpp>

include <boost/random/lagged_fibonacci.hpp>

include <iostream>

include <vector>


int main()
{
  const double mean = 10.0;
  const double sigma = 1.0;
  boost::normal_distribution<double> norm_dist(mean, sigma);
  boost::lagged_fibonacci19937 engine;
  //Make a histogram
  const int size = static_cast<int>(mean) * 2;
  std::vector<int> histo(size,0);
  for (int i=0; i<1000000; ++i)
  {
    const double value = norm_dist.operator () <boost::lagged_fibonacci19937>((engine));
    int index = value;
    index = (index < 0 ? 0 : index);
    index = (index > size - 1 ? size - 1 : index);
    ++histo[index];
  }
  //Output histogram
  for (int i=0; i<size; ++i)
  {
    std::cout << histo[i] << std::endl;
  }
  return 0;
}

Code links

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• <<, stream out operator
• #include
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• endl
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• int
• iostream
• main
• return
• scope operator, ::
• std
• stream out operator, <<