C++11: Random Numbers: Normal Distribution

You can easily create normally distributed numbers. Here is an example:

#include <iostream>
#include <random>
#include <vector>

std::normal_distribution<double>   norm_double_dist_0_9{4.5 /*mean*/,
                                                        2.0 /* sd */};
std::default_random_engine         random_engine{};
const int NbrOfBins    =  10;
const int NbrOfSamples = 100;

int main()
{
  std::vector<int> histogram(NbrOfBins);
  int              sampleValue;

  for (int sample = 0; sample < NbrOfSamples; ++sample)
  {
    sampleValue             = (int)norm_double_dist_0_9(random_engine);
    if (sampleValue < 0) sampleValue = 0;
    if (sampleValue > 9) sampleValue = 9;
    ++histogram[sampleValue];
  }

  for (int bin = 0; bin < NbrOfBins; ++bin)
  {
    std::cout << histogram[bin] << std::endl;
  }
  return 0;
}
/* Output:
     8
     6
     8
     15
     19
     18
     14
     8
     3
     1
*/

Reference: https://isocpp.org/wiki/faq/cpp11-library#std-random