.TH "std::poisson_distribution< _IntType >" 3cxx "libstdc++" \" -*- nroff -*-
.ad l
.nh
.SH NAME
std::poisson_distribution< _IntType > \- A discrete Poisson random number distribution\&.  

.SH SYNOPSIS
.br
.PP
.PP
\fC#include <random>\fP
.SS "Classes"

.in +1c
.ti -1c
.RI "struct \fBparam_type\fP"
.br
.in -1c
.SS "Public Types"

.in +1c
.ti -1c
.RI "\fBtypedef\fP _IntType \fBresult_type\fP"
.br
.in -1c
.SS "Public Member Functions"

.in +1c
.ti -1c
.RI "\fBpoisson_distribution\fP (const \fBparam_type\fP &__p)"
.br
.ti -1c
.RI "\fBpoisson_distribution\fP (double \fB__mean\fP)"
.br
.ti -1c
.RI "template<\fBtypename\fP \fB_ForwardIterator\fP , \fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBvoid\fP \fB__generate\fP (\fB_ForwardIterator\fP __f, \fB_ForwardIterator\fP __t, \fB_UniformRandomNumberGenerator\fP &\fB__urng\fP)"
.br
.ti -1c
.RI "template<\fBtypename\fP \fB_ForwardIterator\fP , \fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBvoid\fP \fB__generate\fP (\fB_ForwardIterator\fP __f, \fB_ForwardIterator\fP __t, \fB_UniformRandomNumberGenerator\fP &\fB__urng\fP, const \fBparam_type\fP &__p)"
.br
.ti -1c
.RI "template<\fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBvoid\fP \fB__generate\fP (\fBresult_type\fP *__f, \fBresult_type\fP *__t, \fB_UniformRandomNumberGenerator\fP &\fB__urng\fP, const \fBparam_type\fP &__p)"
.br
.ti -1c
.RI "\fBresult_type\fP \fBmax\fP () const"
.br
.RI "Returns the least upper bound value of the distribution\&. "
.ti -1c
.RI "double \fBmean\fP () const"
.br
.RI "Returns the distribution parameter \fCmean\fP\&. "
.ti -1c
.RI "\fBresult_type\fP \fBmin\fP () const"
.br
.RI "Returns the greatest lower bound value of the distribution\&. "
.ti -1c
.RI "template<\fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBresult_type\fP \fBoperator()\fP (\fB_UniformRandomNumberGenerator\fP &\fB__urng\fP)"
.br
.RI "Generating functions\&. "
.ti -1c
.RI "template<\fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBresult_type\fP \fBoperator()\fP (\fB_UniformRandomNumberGenerator\fP &\fB__urng\fP, const \fBparam_type\fP &__p)"
.br
.ti -1c
.RI "\fBparam_type\fP \fBparam\fP () const"
.br
.RI "Returns the parameter set of the distribution\&. "
.ti -1c
.RI "\fBvoid\fP \fBparam\fP (const \fBparam_type\fP &\fB__param\fP)"
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.RI "Sets the parameter set of the distribution\&. "
.ti -1c
.RI "\fBvoid\fP \fBreset\fP ()"
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.RI "Resets the distribution state\&. "
.in -1c
.SS "Friends"

.in +1c
.ti -1c
.RI "template<\fBtypename\fP \fB_IntType1\fP , \fBtypename\fP _CharT , \fBtypename\fP _Traits > \fBstd::basic_ostream\fP< _CharT, _Traits > & \fBoperator<<\fP (\fBstd::basic_ostream\fP< _CharT, _Traits > &\fB__os\fP, const \fBstd::poisson_distribution\fP< \fB_IntType1\fP > &__x)"
.br
.RI "Inserts a poisson_distribution random number distribution \fC__x\fP into the output stream \fC__os\fP\&. "
.ti -1c
.RI "bool \fBoperator==\fP (const \fBpoisson_distribution\fP &\fB__d1\fP, const \fBpoisson_distribution\fP &\fB__d2\fP)"
.br
.RI "Return true if two Poisson distributions have the same parameters and the sequences that would be generated are equal\&. "
.ti -1c
.RI "template<\fBtypename\fP \fB_IntType1\fP , \fBtypename\fP _CharT , \fBtypename\fP _Traits > \fBstd::basic_istream\fP< _CharT, _Traits > & \fBoperator>>\fP (\fBstd::basic_istream\fP< _CharT, _Traits > &\fB__is\fP, \fBstd::poisson_distribution\fP< \fB_IntType1\fP > &__x)"
.br
.RI "Extracts a poisson_distribution random number distribution \fC__x\fP from the input stream \fC__is\fP\&. "
.in -1c
.SH "Detailed Description"
.PP 

.SS "template<\fBtypename\fP _IntType = int>
.br
class std::poisson_distribution< _IntType >"A discrete Poisson random number distribution\&. 

The formula for the Poisson probability density function is $p(i|\mu) = \frac{\mu^i}{i!} e^{-\mu}$ where $\mu$ is the parameter of the distribution\&. 
.SH "Member Typedef Documentation"
.PP 
.SS "template<\fBtypename\fP _IntType  = int> \fBtypedef\fP _IntType \fBstd::poisson_distribution\fP< _IntType >::result_type"
The type of the range of the distribution\&. 
.SH "Member Function Documentation"
.PP 
.SS "template<\fBtypename\fP _IntType  = int> \fBresult_type\fP \fBstd::poisson_distribution\fP< _IntType >::max () const\fC [inline]\fP"

.PP
Returns the least upper bound value of the distribution\&. 
.PP
References \fBstd::numeric_limits< _Tp >::max()\fP\&.
.SS "template<\fBtypename\fP _IntType  = int> double \fBstd::poisson_distribution\fP< _IntType >::mean () const\fC [inline]\fP"

.PP
Returns the distribution parameter \fCmean\fP\&. 
.SS "template<\fBtypename\fP _IntType  = int> \fBresult_type\fP \fBstd::poisson_distribution\fP< _IntType >::min () const\fC [inline]\fP"

.PP
Returns the greatest lower bound value of the distribution\&. 
.SS "template<\fBtypename\fP _IntType  = int> template<\fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBresult_type\fP \fBstd::poisson_distribution\fP< _IntType >::operator() (\fB_UniformRandomNumberGenerator\fP & __urng)\fC [inline]\fP"

.PP
Generating functions\&. 
.PP
References \fBstd::poisson_distribution< _IntType >::operator()()\fP\&.
.PP
Referenced by \fBstd::poisson_distribution< _IntType >::operator()()\fP\&.
.SS "template<\fBtypename\fP _IntType > template<\fBtypename\fP \fB_UniformRandomNumberGenerator\fP > \fBpoisson_distribution\fP< _IntType >\fB::result_type\fP \fBstd::poisson_distribution\fP< _IntType >::operator() (\fB_UniformRandomNumberGenerator\fP & __urng, const \fBparam_type\fP & __param)"
A rejection algorithm when mean >= 12 and a simple method based upon the multiplication of uniform random variates otherwise\&. NB: The former is available only if _GLIBCXX_USE_C99_MATH_TR1 is defined\&.
.PP
Reference: Devroye, L\&. Non-Uniform Random Variates Generation\&. Springer-Verlag, New York, 1986, Ch\&. X, Sects\&. 3\&.3 & 3\&.4 (+ Errata!)\&. 
.PP
References \fBstd::abs()\fP, \fBstd::numeric_limits< _Tp >::epsilon()\fP, \fBstd::log()\fP, and \fBstd::numeric_limits< _Tp >::max()\fP\&.
.SS "template<\fBtypename\fP _IntType  = int> \fBparam_type\fP \fBstd::poisson_distribution\fP< _IntType >::param () const\fC [inline]\fP"

.PP
Returns the parameter set of the distribution\&. 
.SS "template<\fBtypename\fP _IntType  = int> \fBvoid\fP \fBstd::poisson_distribution\fP< _IntType >::param (const \fBparam_type\fP & __param)\fC [inline]\fP"

.PP
Sets the parameter set of the distribution\&. 
.PP
\fBParameters\fP
.RS 4
\fI__param\fP The new parameter set of the distribution\&. 
.RE
.PP

.SS "template<\fBtypename\fP _IntType  = int> \fBvoid\fP \fBstd::poisson_distribution\fP< _IntType >::reset ()\fC [inline]\fP"

.PP
Resets the distribution state\&. 
.PP
References \fBstd::normal_distribution< _RealType >::reset()\fP\&.
.SH "Friends And Related Symbol Documentation"
.PP 
.SS "template<\fBtypename\fP _IntType  = int> template<\fBtypename\fP \fB_IntType1\fP , \fBtypename\fP _CharT , \fBtypename\fP _Traits > \fBstd::basic_ostream\fP< _CharT, _Traits > & operator<< (\fBstd::basic_ostream\fP< _CharT, _Traits > & __os, const \fBstd::poisson_distribution\fP< \fB_IntType1\fP > & __x)\fC [friend]\fP"

.PP
Inserts a poisson_distribution random number distribution \fC__x\fP into the output stream \fC__os\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__os\fP An output stream\&. 
.br
\fI__x\fP A poisson_distribution random number distribution\&.
.RE
.PP
\fBReturns\fP
.RS 4
The output stream with the state of \fC__x\fP inserted or in an error state\&. 
.RE
.PP

.SS "template<\fBtypename\fP _IntType  = int> bool operator== (const \fBpoisson_distribution\fP< _IntType > & __d1, const \fBpoisson_distribution\fP< _IntType > & __d2)\fC [friend]\fP"

.PP
Return true if two Poisson distributions have the same parameters and the sequences that would be generated are equal\&. 
.SS "template<\fBtypename\fP _IntType  = int> template<\fBtypename\fP \fB_IntType1\fP , \fBtypename\fP _CharT , \fBtypename\fP _Traits > \fBstd::basic_istream\fP< _CharT, _Traits > & operator>> (\fBstd::basic_istream\fP< _CharT, _Traits > & __is, \fBstd::poisson_distribution\fP< \fB_IntType1\fP > & __x)\fC [friend]\fP"

.PP
Extracts a poisson_distribution random number distribution \fC__x\fP from the input stream \fC__is\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__is\fP An input stream\&. 
.br
\fI__x\fP A poisson_distribution random number generator engine\&.
.RE
.PP
\fBReturns\fP
.RS 4
The input stream with \fC__x\fP extracted or in an error state\&. 
.RE
.PP


.SH "Author"
.PP 
Generated automatically by Doxygen for libstdc++ from the source code\&.