libstdc++
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std::linear_congruential< _UIntType, __a, __c, __m > Class Template Reference
Random Number Generators

Public Types

typedef _UIntType result_type
 

Public Member Functions

 linear_congruential (unsigned long __x0=1)
 
template<class _Gen >
 linear_congruential (_Gen &__g)
 
result_type max () const
 
result_type min () const
 
result_type operator() ()
 
void seed (unsigned long __s=1)
 
template<class _Gen >
void seed (_Gen &__g)
 

Static Public Attributes

static const _UIntType increment
 
static const _UIntType modulus
 
static const _UIntType multiplier
 

Friends

bool operator!= (const linear_congruential &__lhs, const linear_congruential &__rhs)
 
template<class _UIntType1 , _UIntType1 __a1, _UIntType1 __c1, _UIntType1 __m1, typename _CharT , typename _Traits >
std::basic_ostream< _CharT,
_Traits > & 		operator<< (std::basic_ostream< _CharT, _Traits > &__os, const linear_congruential< _UIntType1, __a1, __c1, __m1 > &__lcr)
 
bool operator== (const linear_congruential &__lhs, const linear_congruential &__rhs)
 
template<class _UIntType1 , _UIntType1 __a1, _UIntType1 __c1, _UIntType1 __m1, typename _CharT , typename _Traits >
std::basic_istream< _CharT,
_Traits > & 		operator>> (std::basic_istream< _CharT, _Traits > &__is, linear_congruential< _UIntType1, __a1, __c1, __m1 > &__lcr)
 

Detailed Description

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
class std::linear_congruential< _UIntType, __a, __c, __m >

A model of a linear congruential random number generator.

A random number generator that produces pseudorandom numbers using the linear function $x_{i+1}\leftarrow(ax_{i} + c) \bmod m $.

The template parameter _UIntType must be an unsigned integral type large enough to store values up to (__m-1). If the template parameter __m is 0, the modulus __m used is std::numeric_limits<_UIntType>::max() plus 1. Otherwise, the template parameters __a and __c must be less than __m.

The size of the state is $ 1 $.

Definition at line 346 of file tr1_impl/random.

Member Typedef Documentation

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
typedef _UIntType std::linear_congruential< _UIntType, __a, __c, __m >::result_type

The type of the generated random value.

Definition at line 353 of file tr1_impl/random.

Constructor & Destructor Documentation

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
std::linear_congruential< _UIntType, __a, __c, __m >::linear_congruential ( unsigned long  __x0 = 1)
inlineexplicit

Constructs a linear_congruential random number generator engine with seed __s. The default seed value is 1.

Parameters
__sThe initial seed value.

Definition at line 369 of file tr1_impl/random.

References std::linear_congruential< _UIntType, __a, __c, __m >::seed().

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
template<class _Gen >
std::linear_congruential< _UIntType, __a, __c, __m >::linear_congruential ( _Gen &  __g)
inline

Constructs a linear_congruential random number generator engine seeded from the generator function __g.

Parameters
__gThe seed generator function.

Definition at line 379 of file tr1_impl/random.

References std::linear_congruential< _UIntType, __a, __c, __m >::seed().

Member Function Documentation

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
result_type std::linear_congruential< _UIntType, __a, __c, __m >::max ( ) const
inline

Gets the largest possible value in the output range.

Definition at line 416 of file tr1_impl/random.

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
result_type std::linear_congruential< _UIntType, __a, __c, __m >::min ( ) const
inline

Gets the smallest possible value in the output range.

The minimum depends on the __c parameter: if it is zero, the minimum generated must be > 0, otherwise 0 is allowed.

Definition at line 409 of file tr1_impl/random.

template<class _UIntType , _UIntType __a, _UIntType __c, _UIntType __m>
linear_congruential< _UIntType, __a, __c, __m >::result_type std::linear_congruential< _UIntType, __a, __c, __m >::operator() ( )

Gets the next random number in the sequence.

Gets the next generated value in sequence.

Definition at line 130 of file random.tcc.

template<class _UIntType , _UIntType __a, _UIntType __c, _UIntType __m>
void std::linear_congruential< _UIntType, __a, __c, __m >::seed ( unsigned long  __x0 = 1)

Reseeds the linear_congruential random number generator engine sequence to the seed __s.

Parameters
__sThe new seed.

Seeds the LCR with integral value __x0, adjusted so that the ring identity is never a member of the convergence set.

Definition at line 98 of file random.tcc.

Referenced by std::linear_congruential< _UIntType, __a, __c, __m >::linear_congruential(), and std::linear_congruential< _UIntType, __a, __c, __m >::seed().

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
template<class _Gen >
void std::linear_congruential< _UIntType, __a, __c, __m >::seed ( _Gen &  __g)
inline

Reseeds the linear_congruential random number generator engine sequence using values from the generator function __g.

Parameters
__gthe seed generator function.

Definition at line 399 of file tr1_impl/random.

References std::linear_congruential< _UIntType, __a, __c, __m >::seed().

Friends And Related Function Documentation

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
bool operator!= ( const linear_congruential< _UIntType, __a, __c, __m > &  __lhs,
const linear_congruential< _UIntType, __a, __c, __m > &  __rhs 
)
friend

Compares two linear congruential random number generator objects of the same type for inequality.

Parameters
__lhsA linear congruential random number generator object.
__rhsAnother linear congruential random number generator obj.
Returns
true if the two objects are not equal, false otherwise.

Definition at line 449 of file tr1_impl/random.

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
template<class _UIntType1 , _UIntType1 __a1, _UIntType1 __c1, _UIntType1 __m1, typename _CharT , typename _Traits >
std::basic_ostream<_CharT, _Traits>& operator<< ( std::basic_ostream< _CharT, _Traits > &  __os,
const linear_congruential< _UIntType1, __a1, __c1, __m1 > &  __lcr 
)
friend

Writes the textual representation of the state x(i) of x to __os.

Parameters
__osThe output stream.
__lcrA % linear_congruential random number generator.
Returns
__os.
template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
bool operator== ( const linear_congruential< _UIntType, __a, __c, __m > &  __lhs,
const linear_congruential< _UIntType, __a, __c, __m > &  __rhs 
)
friend

Compares two linear congruential random number generator objects of the same type for equality.

Parameters
__lhsA linear congruential random number generator object.
__rhsAnother linear congruential random number generator obj.
Returns
true if the two objects are equal, false otherwise.

Definition at line 435 of file tr1_impl/random.

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
template<class _UIntType1 , _UIntType1 __a1, _UIntType1 __c1, _UIntType1 __m1, typename _CharT , typename _Traits >
std::basic_istream<_CharT, _Traits>& operator>> ( std::basic_istream< _CharT, _Traits > &  __is,
linear_congruential< _UIntType1, __a1, __c1, __m1 > &  __lcr 
)
friend

Sets the state of the engine by reading its textual representation from __is.

The textual representation must have been previously written using an output stream whose imbued locale and whose type's template specialization arguments _CharT and _Traits were the same as those of __is.

Parameters
__isThe input stream.
__lcrA % linear_congruential random number generator.
Returns
__is.

Member Data Documentation

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
const _UIntType std::linear_congruential< _UIntType, __a, __c, __m >::increment
static

An increment.

Definition at line 358 of file tr1_impl/random.

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
const _UIntType std::linear_congruential< _UIntType, __a, __c, __m >::modulus
static

The modulus.

Definition at line 360 of file tr1_impl/random.

template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m>
const _UIntType std::linear_congruential< _UIntType, __a, __c, __m >::multiplier
static

The multiplier.

Definition at line 356 of file tr1_impl/random.

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