libstdc++
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std::exponential_distribution< _RealType > Class Template Reference
Continuous Distributions

Public Types

typedef _RealType input_type
 
typedef _RealType result_type
 

Public Member Functions

 exponential_distribution (const result_type &__lambda=result_type(1))
 
_RealType lambda () const
 
template<class _UniformRandomNumberGenerator >
result_type operator() (_UniformRandomNumberGenerator &__urng)
 
void reset ()
 

Friends

template<typename _RealType1 , typename _CharT , typename _Traits >
std::basic_ostream< _CharT,
_Traits > & 		operator<< (std::basic_ostream< _CharT, _Traits > &__os, const exponential_distribution< _RealType1 > &__x)
 
template<typename _CharT , typename _Traits >
std::basic_istream< _CharT,
_Traits > & 		operator>> (std::basic_istream< _CharT, _Traits > &__is, exponential_distribution &__x)
 

Detailed Description

template<typename _RealType = double>
class std::exponential_distribution< _RealType >

An exponential continuous distribution for random numbers.

The formula for the exponential probability mass function is $ p(x) = \lambda e^{-\lambda x} $.

Distribution Statistics
Mean$ \frac{1}{\lambda} $
Median$ \frac{\ln 2}{\lambda} $
Mode$ zero $
Range$[0, \infty]$
Standard Deviation$ \frac{1}{\lambda} $

Definition at line 2148 of file tr1_impl/random.

Constructor & Destructor Documentation

template<typename _RealType = double>
std::exponential_distribution< _RealType >::exponential_distribution ( const result_type &  __lambda = result_type(1))
inlineexplicit

Constructs an exponential distribution with inverse scale parameter $ \lambda $.

Definition at line 2161 of file tr1_impl/random.

Member Function Documentation

template<typename _RealType = double>
_RealType std::exponential_distribution< _RealType >::lambda ( ) const
inline

Gets the inverse scale parameter of the distribution.

Definition at line 2171 of file tr1_impl/random.

template<typename _RealType = double>
void std::exponential_distribution< _RealType >::reset ( )
inline

Resets the distribution.

Has no effect on exponential distributions.

Definition at line 2180 of file tr1_impl/random.

Friends And Related Function Documentation

template<typename _RealType = double>
template<typename _RealType1 , typename _CharT , typename _Traits >
std::basic_ostream<_CharT, _Traits>& operator<< ( std::basic_ostream< _CharT, _Traits > &  __os,
const exponential_distribution< _RealType1 > &  __x 
)
friend

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

Parameters
__osAn output stream.
__xA exponential_distribution random number distribution.
Returns
The output stream with the state of __x inserted or in an error state.
template<typename _RealType = double>
template<typename _CharT , typename _Traits >
std::basic_istream<_CharT, _Traits>& operator>> ( std::basic_istream< _CharT, _Traits > &  __is,
exponential_distribution< _RealType > &  __x 
)
friend

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

Parameters
__isAn input stream.
__xA exponential_distribution random number generator engine.
Returns
The input stream with __x extracted or in an error state.

Definition at line 2214 of file tr1_impl/random.

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