std::discrete_distribution<IntType>:: discrete_distribution

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std::discrete_distribution
discrete_distribution ( ) ;
(1) (since C++11)
template < class InputIt >
discrete_distribution ( InputIt first, InputIt last ) ;
(2) (since C++11)
discrete_distribution ( std:: initializer_list < double > weights ) ;
(3) (since C++11)
template < class UnaryOperation >

discrete_distribution ( std:: size_t count, double xmin, double xmax,

UnaryOperation unary_op ) ;
(4) (since C++11)
explicit discrete_distribution ( const param_type & params ) ;
(5) (since C++11)

Constructs a new distribution object.

1) Default constructor. Constructs the distribution with a single weight p = {1 }. This distribution will always generate ​ 0 ​ .
2) Constructs the distribution with weights in the range [ first , last ) . If first == last , the effects are the same as of the default constructor.
3) Constructs the distribution with weights in weights . Effectively calls discrete_distribution ( weights. begin ( ) , weights. end ( ) ) .
4) Constructs the distribution with count weights that are generated using function unary_op . Each of the weights is equal to w i = unary_op(xmin + δ(i + 0.5)) , where δ =
(xmax − xmin)
count
and i ∈ {0, ..., count − 1 }. xmin and xmax must be such that δ > 0 . If count == 0 the effects are the same as of the default constructor.
5) Constructs the distribution with params as the distribution parameters.

Parameters

first, last - the range of elements defining the numbers to use as weights. The type of the elements referred by InputIterator must be convertible to double
weights - initializer list containing the weights
unary_op - unary operation function object that will be applied.

The signature of the function should be equivalent to the following:

Ret fun ( const Type & a ) ;

The signature does not need to have const & .
The type Type must be such that an object of type double can be dereferenced and then implicitly converted to Type . The type Ret must be such that an object of type double can be dereferenced and assigned a value of type Ret . ​

params - the distribution parameter set
Type requirements
-
InputIt must meet the requirements of LegacyInputIterator .
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