std::poisson_distribution::mean
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                    < cpp | numeric | random | poisson distribution
                    
                                                            
                    |   double mean() const; 
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(since C++11) | |
Returns the μ distribution parameter (mean number of occurrences of the event).
[edit] Parameters
(none)
[edit] Return value
Floating point value identifying the mean number of occurrences of the event
[edit] See also
|    gets or sets the distribution parameter object   (public member function)  | 
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