std::gamma_distribution::gamma_distribution
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                    < cpp | numeric | random | gamma distribution
                    
                                                            
                    | explicit gamma_distribution( RealType alpha = 1.0, RealType beta = 1.0 ); | (1) | (since C++11) | 
| explicit gamma_distribution( const param_type& params ); | (2) | (since C++11) | 
Constructs a new distribution object. The first version uses alpha and beta as the distribution parameters, the second version uses params as the distribution parameters.
[edit] Parameters
| alpha | - | the α distribution parameter (shape) | 
| beta | - | the β distribution parameter (scale) | 
| params | - | the distribution parameter set | 


