std::weibull_distribution::weibull_distribution
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                    < cpp | numeric | random | weibull distribution
                    
                                                            
                    | explicit weibull_distribution( RealType a = 1.0, RealType b = 1.0 ); | (1) | (since C++11) | 
| explicit weibull_distribution( const param_type& params ); | (2) | (since C++11) | 
Constructs a new distribution object. The first version uses a and b as the distribution parameters, the second version uses params as the distribution parameters.
Parameters
| a | - | the a distribution parameter (shape) | 
| b | - | the b distribution parameter (scale) | 
| params | - | the distribution parameter set |