std::gamma_distribution

From cppreference.com
 
 
 
Pseudo-random number generation
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Poisson distributions
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gamma_distribution (C++11)
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C library
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Defined in header <random>
template< class RealType = double >
class gamma_distribution;
(since C++11)

Produces random positive integer values x, distributed according to probability density function:

P(x|α,β) =
e-x/β
βα
· Γ(α)
· xα-1

where α is known as the shape parameter and β is known as the scale parameter.

For integer α, the value obtained is the sum of α independent exponentially distributed random variables, each of which has a mean of β

Contents

[edit] Member types

Member type Definition
result_type RealType
param_type the type of the parameter set, unspecified

[edit] Member functions

constructs new distribution
(public member function)
resets the internal state of the distribution
(public member function)
Generation
generates the next random number in the distribution
(public member function)
Characteristics
returns the α distribution parameter (shape)
(public member function)
returns the β distribution parameter (scale)
(public member function)
gets or sets the distribution parameter object
(public member function)
returns the minimum potentially generated value
(public member function)
returns the maximum potentially generated value
(public member function)

[edit] Non-member functions

compares two distribution objects
(function)
performs stream input and output on pseudo-random number distribution
(function)

[edit] Example

[edit] External links

Weisstein, Eric W. "Gamma Distribution." From MathWorld--A Wolfram Web Resource.