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normal_distribution::normal_distribution

Constructs the distribution.

normal_distribution(result_type mean0 = result_type(0.0),
    result_type sigma0 = result_type(1.0));
explicit normal_distribution(const param_type& par0);

Parameters

  • mean0
    The mean distribution parameter.

  • sigma0
    The sigma distribution parameter.

  • par0
    The parameter package used to construct the distribution.

Remarks

Precondition: 0.0 <= sigma0

The first constructor constructs an object whose stored value stored_mean holds the value mean0 and whose stored value stored_sigma holds the value sigma0.

The second constructor constructs an object whose stored parameters are initialized from par0.

Example

 

// std_tr1__random__normal_distribution_construct.cpp 
// compile with: /EHsc 
#include <random> 
#include <iostream> 
 
typedef std::ranlux64_base_01 Myeng; 
typedef std::normal_distribution<double> Mydist; 
int main() 
    { 
    Myeng eng; 
    Mydist dist(1.5, 2.0); 
    Mydist::input_type engval = eng(); 
    Mydist::result_type distval = dist(eng); 
 
    distval = distval;  // to quiet "unused" warnings 
    engval = engval; 
 
    std::cout << "mean == " << dist.mean() << std::endl; 
    std::cout << "sigma == " << dist.sigma() << std::endl; 
 
    dist.reset(); // discard any cached values 
    std::cout << "a random value == " << dist(eng) << std::endl; 
    std::cout << "a random value == " << dist(eng) << std::endl; 
    std::cout << "a random value == " << dist(eng) << std::endl; 
 
    return (0); 
    } 
 
mean == 1.5
sigma == 2
a random value == 0.0275648
a random value == 0.0738393
a random value == 4.47125

Requirements

Header: <random>

Namespace: std

See Also

Reference

<random>

normal_distribution Class

Other Resources

<random> Members