public member function
<random>

std::normal_distribution::(constructor)

(1)
explicit normal_distribution ( result_type mean = 0.0, result_type stddev = 1.0 );
(2)
explicit normal_distribution ( const param_type& parm );
Construct normal distribution
Constructs a normal_distribution object, adopting the distribution parameters specified either by mean and stddev or by object parm.

Parameters

mean
Mean of the distribution (its expected value, μ). Which coincides with the location of its peak.
result_type is a member type that represents the type of the random numbers generated on each call to operator(). It is defined as an alias of the first class template parameter (RealType).
stddev
Standard deviation (σ): The square root of variance, representing the dispersion of values from the distribution mean.
This shall be a positive value (σ>0).
result_type is a member type that represents the type of the random numbers generated on each call to operator(). It is defined as an alias of the first class template parameter (RealType).
parm
An object representing the distribution's parameters, obtained by a call to member function param.
param_type is a member type.

Example

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// normal_distribution example
#include <iostream>
#include <chrono>
#include <random>

int main()
{
  // construct a trivial random generator engine from a time-based seed:
  unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
  std::default_random_engine generator (seed);

  std::normal_distribution<double> distribution (0.0,1.0);

  std::cout << "some Normal-distributed(0.0,1.0) results:" << std::endl;
  for (int i=0; i<10; ++i)
    std::cout << distribution(generator) << std::endl;

  return 0;
}


Possible output:
some Normal-distributed(0.0,1.0) results:
-0.246719
0.189872
-1.53603
-1.58534
0.0569692
2.22
1.34839
-0.512007
0.450768
-0.0999992

Complexity

Constant.

See also