std::poisson_distribution<IntType>::poisson_distribution

 

C++

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has_single_bit (C++20)     bit_cast (C++20) bit_ceil (C++20) bit_floor (C++20) bit_width (C++20) rotl (C++20) rotr (C++20)	popcount (C++20) countl_zero (C++20) countl_one (C++20) countr_zero (C++20) countr_one (C++20) byteswap (C++23) endian (C++20)

 

Pseudo-random number generation

Uniform random bit generators   uniform_random_bit_generator (C++20) Random number engines linear_congruential_engine (C++11) mersenne_twister_engine (C++11) subtract_with_carry_engine (C++11) philox_engine (C++26) Random number engine adaptors discard_block_engine (C++11) independent_bits_engine (C++11) shuffle_order_engine (C++11) Predefined random number generators Non-deterministic random numbers random_device (C++11) Utilities generate_canonical (C++11) seed_seq (C++11) Random number algorithms ranges::generate_random (C++26) C random library rand    srand    RAND_MAX

Random number distributions Uniform distributions uniform_int_distribution (C++11) uniform_real_distribution (C++11) generate_canonical (C++11) Bernoulli distributions bernoulli_distribution (C++11) binomial_distribution (C++11) negative_binomial_distribution (C++11) geometric_distribution (C++11) Poisson distributions poisson_distribution (C++11) exponential_distribution (C++11) gamma_distribution (C++11) weibull_distribution (C++11) extreme_value_distribution (C++11) Normal distributions normal_distribution (C++11) lognormal_distribution (C++11) chi_squared_distribution (C++11) cauchy_distribution (C++11) fisher_f_distribution (C++11) student_t_distribution (C++11) Sampling distributions discrete_distribution (C++11) piecewise_constant_distribution (C++11) piecewise_linear_distribution (C++11)

 

std::poisson_distribution

Member functions

poisson_distribution::poisson_distribution

poisson_distribution::reset

Generation

poisson_distribution::operator()

Characteristics

poisson_distribution::mean

poisson_distribution::param

poisson_distribution::min

poisson_distribution::max

Non-member functions

operator==operator!= (C++11)(C++11)(until C++20)

operator<<operator>> (C++11)(C++11)

 

poisson_distribution() : poisson_distribution(1.0) {}	(1)	(since C++11)
explicit poisson_distribution( double mean );	(2)	(since C++11)
explicit poisson_distribution( const param_type& params );	(3)	(since C++11)

Constructs a new distribution object.

1) Uses 1.0 as the distribution parameter.

2) Uses mean as the distribution parameter.

3) Uses params as the distribution parameter.

Parameters

mean	-	the μ distribution parameter (the mean of the distribution)
params	-	the distribution parameter set

Notes

Requires that 0 < mean.

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
P0935R0	C++11	default constructor was explicit	made implicit