Inheritance diagram for std::gamma_distribution:

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Classes

struct param_type

Public Types

typedef _RealType result_type

Public Member Functions

gamma_distribution (_RealType __alpha_val=_RealType(1), _RealType __beta_val=_RealType(1))
gamma_distribution (const param_type &__p)
_RealType alpha () const
_RealType beta () const
result_type max () const
result_type min () const
template<typename _UniformRandomNumberGenerator > result_type operator() (_UniformRandomNumberGenerator &__urng)
template<typename _UniformRandomNumberGenerator > result_type operator() (_UniformRandomNumberGenerator &__urng, const param_type &__p)
param_type param () const
void param (const param_type &__param)
void reset ()

Friends

template<typename _RealType1 , typename _CharT , typename _Traits > std::basic_ostream< _CharT,
_Traits > & operator<< (std::basic_ostream< _CharT, _Traits > &, const std::gamma_distribution< _RealType1 > &)
template<typename _RealType1 > bool operator== (const std::gamma_distribution< _RealType1 > &__d1, const std::gamma_distribution< _RealType1 > &__d2)
template<typename _RealType1 , typename _CharT , typename _Traits > std::basic_istream< _CharT,
_Traits > & operator>> (std::basic_istream< _CharT, _Traits > &, std::gamma_distribution< _RealType1 > &)

Detailed Description

A gamma continuous distribution for random numbers.

The formula for the gamma probability density function is:

$p(x|\alpha,\beta) = \frac{1}{\beta\Gamma(\alpha)} (x/\beta)^{\alpha - 1} e^{-x/\beta}$

Member Typedef Documentation

typedef _RealType std::gamma_distribution::result_type

The type of the range of the distribution.

Definition at line 2334 of file random.h.

Constructor & Destructor Documentation

std::gamma_distribution::gamma_distribution	(	_RealType	__alpha_val = `_RealType(1)`,
		_RealType	__beta_val = `_RealType(1)`
	)		`[inline, explicit]`

Constructs a gamma distribution with parameters $\alpha$ and $\beta$ .

Definition at line 2379 of file random.h.

Member Function Documentation

_RealType std::gamma_distribution::alpha ( ) const [inline]

Returns the $\alpha$ of the distribution.

Definition at line 2400 of file random.h.

_RealType std::gamma_distribution::beta ( ) const [inline]

Returns the $\beta$ of the distribution.

Definition at line 2407 of file random.h.

result_type std::gamma_distribution::max ( ) const [inline]

Returns the least upper bound value of the distribution.

Definition at line 2436 of file random.h.

Referenced by std::gamma_distribution< result_type >::max().

result_type std::gamma_distribution::min ( ) const [inline]

Returns the greatest lower bound value of the distribution.

Definition at line 2429 of file random.h.

template<typename _UniformRandomNumberGenerator >

result_type std::gamma_distribution::operator() ( _UniformRandomNumberGenerator & __urng ) [inline]

Generating functions.

Definition at line 2444 of file random.h.

Referenced by std::gamma_distribution< result_type >::operator()().

template<typename _UniformRandomNumberGenerator >

gamma_distribution< _RealType >::result_type std::gamma_distribution::operator()	(	_UniformRandomNumberGenerator &	__urng,
		const param_type &	__param
	)

Marsaglia, G. and Tsang, W. W. "A Simple Method for Generating Gamma Variables" ACM Transactions on Mathematical Software, 26, 3, 363-372, 2000.

Definition at line 2017 of file random.tcc.

References std::log(), and std::pow().

param_type std::gamma_distribution::param ( ) const [inline]

Returns the parameter set of the distribution.

Definition at line 2414 of file random.h.

Referenced by std::gamma_distribution< result_type >::operator()().

void std::gamma_distribution::param ( const param_type & __param ) [inline]

Sets the parameter set of the distribution.

Parameters:

__param The new parameter set of the distribution.

Definition at line 2422 of file random.h.

void std::gamma_distribution::reset ( ) [inline]

Resets the distribution state.

Definition at line 2393 of file random.h.

Referenced by std::chi_squared_distribution::reset(), std::fisher_f_distribution::reset(), std::student_t_distribution::reset(), and std::negative_binomial_distribution::reset().

Friends And Related Function Documentation

template<typename _RealType1 , typename _CharT , typename _Traits >

std::basic_ostream<_CharT, _Traits>& operator<<	(	std::basic_ostream< _CharT, _Traits > &	,
		const std::gamma_distribution< _RealType1 > &
	)		`[friend]`

Inserts a gamma_distribution random number distribution __x into the output stream __os.

Parameters:

__os	An output stream.
__x	A gamma_distribution random number distribution.

Returns:: The output stream with the state of __x inserted or in an error state.

template<typename _RealType1 >

bool operator==	(	const std::gamma_distribution< _RealType1 > &	__d1,
		const std::gamma_distribution< _RealType1 > &	__d2
	)		`[friend]`

Return true if two gamma distributions have the same parameters and the sequences that would be generated are equal.

Definition at line 2459 of file random.h.

template<typename _RealType1 , typename _CharT , typename _Traits >

std::basic_istream<_CharT, _Traits>& operator>>	(	std::basic_istream< _CharT, _Traits > &	,
		std::gamma_distribution< _RealType1 > &
	)		`[friend]`

Extracts a gamma_distribution random number distribution __x from the input stream __is.

Parameters:

__is	An input stream.
__x	A gamma_distribution random number generator engine.

Returns:: The input stream with __x extracted or in an error state.

The documentation for this class was generated from the following files: