0,0 → 1,2417 |
// random number generation -*- C++ -*- |
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// Copyright (C) 2009-2015 Free Software Foundation, Inc. |
// |
// This file is part of the GNU ISO C++ Library. This library is free |
// software; you can redistribute it and/or modify it under the |
// terms of the GNU General Public License as published by the |
// Free Software Foundation; either version 3, or (at your option) |
// any later version. |
|
// This library is distributed in the hope that it will be useful, |
// but WITHOUT ANY WARRANTY; without even the implied warranty of |
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
// GNU General Public License for more details. |
|
// Under Section 7 of GPL version 3, you are granted additional |
// permissions described in the GCC Runtime Library Exception, version |
// 3.1, as published by the Free Software Foundation. |
|
// You should have received a copy of the GNU General Public License and |
// a copy of the GCC Runtime Library Exception along with this program; |
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
// <http://www.gnu.org/licenses/>. |
|
/** |
* @file tr1/random.h |
* This is an internal header file, included by other library headers. |
* Do not attempt to use it directly. @headername{tr1/random} |
*/ |
|
#ifndef _GLIBCXX_TR1_RANDOM_H |
#define _GLIBCXX_TR1_RANDOM_H 1 |
|
#pragma GCC system_header |
|
namespace std _GLIBCXX_VISIBILITY(default) |
{ |
namespace tr1 |
{ |
// [5.1] Random number generation |
|
/** |
* @addtogroup tr1_random Random Number Generation |
* A facility for generating random numbers on selected distributions. |
* @{ |
*/ |
|
/* |
* Implementation-space details. |
*/ |
namespace __detail |
{ |
_GLIBCXX_BEGIN_NAMESPACE_VERSION |
|
template<typename _UIntType, int __w, |
bool = __w < std::numeric_limits<_UIntType>::digits> |
struct _Shift |
{ static const _UIntType __value = 0; }; |
|
template<typename _UIntType, int __w> |
struct _Shift<_UIntType, __w, true> |
{ static const _UIntType __value = _UIntType(1) << __w; }; |
|
template<typename _Tp, _Tp __a, _Tp __c, _Tp __m, bool> |
struct _Mod; |
|
// Dispatch based on modulus value to prevent divide-by-zero compile-time |
// errors when m == 0. |
template<typename _Tp, _Tp __a, _Tp __c, _Tp __m> |
inline _Tp |
__mod(_Tp __x) |
{ return _Mod<_Tp, __a, __c, __m, __m == 0>::__calc(__x); } |
|
typedef __gnu_cxx::__conditional_type<(sizeof(unsigned) == 4), |
unsigned, unsigned long>::__type _UInt32Type; |
|
/* |
* An adaptor class for converting the output of any Generator into |
* the input for a specific Distribution. |
*/ |
template<typename _Engine, typename _Distribution> |
struct _Adaptor |
{ |
typedef typename remove_reference<_Engine>::type _BEngine; |
typedef typename _BEngine::result_type _Engine_result_type; |
typedef typename _Distribution::input_type result_type; |
|
public: |
_Adaptor(const _Engine& __g) |
: _M_g(__g) { } |
|
result_type |
min() const |
{ |
result_type __return_value; |
if (is_integral<_Engine_result_type>::value |
&& is_integral<result_type>::value) |
__return_value = _M_g.min(); |
else |
__return_value = result_type(0); |
return __return_value; |
} |
|
result_type |
max() const |
{ |
result_type __return_value; |
if (is_integral<_Engine_result_type>::value |
&& is_integral<result_type>::value) |
__return_value = _M_g.max(); |
else if (!is_integral<result_type>::value) |
__return_value = result_type(1); |
else |
__return_value = std::numeric_limits<result_type>::max() - 1; |
return __return_value; |
} |
|
/* |
* Converts a value generated by the adapted random number generator |
* into a value in the input domain for the dependent random number |
* distribution. |
* |
* Because the type traits are compile time constants only the |
* appropriate clause of the if statements will actually be emitted |
* by the compiler. |
*/ |
result_type |
operator()() |
{ |
result_type __return_value; |
if (is_integral<_Engine_result_type>::value |
&& is_integral<result_type>::value) |
__return_value = _M_g(); |
else if (!is_integral<_Engine_result_type>::value |
&& !is_integral<result_type>::value) |
__return_value = result_type(_M_g() - _M_g.min()) |
/ result_type(_M_g.max() - _M_g.min()); |
else if (is_integral<_Engine_result_type>::value |
&& !is_integral<result_type>::value) |
__return_value = result_type(_M_g() - _M_g.min()) |
/ result_type(_M_g.max() - _M_g.min() + result_type(1)); |
else |
__return_value = (((_M_g() - _M_g.min()) |
/ (_M_g.max() - _M_g.min())) |
* std::numeric_limits<result_type>::max()); |
return __return_value; |
} |
|
private: |
_Engine _M_g; |
}; |
|
// Specialization for _Engine*. |
template<typename _Engine, typename _Distribution> |
struct _Adaptor<_Engine*, _Distribution> |
{ |
typedef typename _Engine::result_type _Engine_result_type; |
typedef typename _Distribution::input_type result_type; |
|
public: |
_Adaptor(_Engine* __g) |
: _M_g(__g) { } |
|
result_type |
min() const |
{ |
result_type __return_value; |
if (is_integral<_Engine_result_type>::value |
&& is_integral<result_type>::value) |
__return_value = _M_g->min(); |
else |
__return_value = result_type(0); |
return __return_value; |
} |
|
result_type |
max() const |
{ |
result_type __return_value; |
if (is_integral<_Engine_result_type>::value |
&& is_integral<result_type>::value) |
__return_value = _M_g->max(); |
else if (!is_integral<result_type>::value) |
__return_value = result_type(1); |
else |
__return_value = std::numeric_limits<result_type>::max() - 1; |
return __return_value; |
} |
|
result_type |
operator()() |
{ |
result_type __return_value; |
if (is_integral<_Engine_result_type>::value |
&& is_integral<result_type>::value) |
__return_value = (*_M_g)(); |
else if (!is_integral<_Engine_result_type>::value |
&& !is_integral<result_type>::value) |
__return_value = result_type((*_M_g)() - _M_g->min()) |
/ result_type(_M_g->max() - _M_g->min()); |
else if (is_integral<_Engine_result_type>::value |
&& !is_integral<result_type>::value) |
__return_value = result_type((*_M_g)() - _M_g->min()) |
/ result_type(_M_g->max() - _M_g->min() + result_type(1)); |
else |
__return_value = ((((*_M_g)() - _M_g->min()) |
/ (_M_g->max() - _M_g->min())) |
* std::numeric_limits<result_type>::max()); |
return __return_value; |
} |
|
private: |
_Engine* _M_g; |
}; |
|
_GLIBCXX_END_NAMESPACE_VERSION |
} // namespace __detail |
|
_GLIBCXX_BEGIN_NAMESPACE_VERSION |
|
/** |
* Produces random numbers on a given distribution function using a |
* non-uniform random number generation engine. |
* |
* @todo the engine_value_type needs to be studied more carefully. |
*/ |
template<typename _Engine, typename _Dist> |
class variate_generator |
{ |
// Concept requirements. |
__glibcxx_class_requires(_Engine, _CopyConstructibleConcept) |
// __glibcxx_class_requires(_Engine, _EngineConcept) |
// __glibcxx_class_requires(_Dist, _EngineConcept) |
|
public: |
typedef _Engine engine_type; |
typedef __detail::_Adaptor<_Engine, _Dist> engine_value_type; |
typedef _Dist distribution_type; |
typedef typename _Dist::result_type result_type; |
|
// tr1:5.1.1 table 5.1 requirement |
typedef typename __gnu_cxx::__enable_if< |
is_arithmetic<result_type>::value, result_type>::__type _IsValidType; |
|
/** |
* Constructs a variate generator with the uniform random number |
* generator @p __eng for the random distribution @p __dist. |
* |
* @throws Any exceptions which may thrown by the copy constructors of |
* the @p _Engine or @p _Dist objects. |
*/ |
variate_generator(engine_type __eng, distribution_type __dist) |
: _M_engine(__eng), _M_dist(__dist) { } |
|
/** |
* Gets the next generated value on the distribution. |
*/ |
result_type |
operator()() |
{ return _M_dist(_M_engine); } |
|
/** |
* WTF? |
*/ |
template<typename _Tp> |
result_type |
operator()(_Tp __value) |
{ return _M_dist(_M_engine, __value); } |
|
/** |
* Gets a reference to the underlying uniform random number generator |
* object. |
*/ |
engine_value_type& |
engine() |
{ return _M_engine; } |
|
/** |
* Gets a const reference to the underlying uniform random number |
* generator object. |
*/ |
const engine_value_type& |
engine() const |
{ return _M_engine; } |
|
/** |
* Gets a reference to the underlying random distribution. |
*/ |
distribution_type& |
distribution() |
{ return _M_dist; } |
|
/** |
* Gets a const reference to the underlying random distribution. |
*/ |
const distribution_type& |
distribution() const |
{ return _M_dist; } |
|
/** |
* Gets the closed lower bound of the distribution interval. |
*/ |
result_type |
min() const |
{ return this->distribution().min(); } |
|
/** |
* Gets the closed upper bound of the distribution interval. |
*/ |
result_type |
max() const |
{ return this->distribution().max(); } |
|
private: |
engine_value_type _M_engine; |
distribution_type _M_dist; |
}; |
|
|
/** |
* @addtogroup tr1_random_generators Random Number Generators |
* @ingroup tr1_random |
* |
* These classes define objects which provide random or pseudorandom |
* numbers, either from a discrete or a continuous interval. The |
* random number generator supplied as a part of this library are |
* all uniform random number generators which provide a sequence of |
* random number uniformly distributed over their range. |
* |
* A number generator is a function object with an operator() that |
* takes zero arguments and returns a number. |
* |
* A compliant random number generator must satisfy the following |
* requirements. <table border=1 cellpadding=10 cellspacing=0> |
* <caption align=top>Random Number Generator Requirements</caption> |
* <tr><td>To be documented.</td></tr> </table> |
* |
* @{ |
*/ |
|
/** |
* @brief A model of a linear congruential random number generator. |
* |
* A random number generator that produces pseudorandom numbers using the |
* linear function @f$x_{i+1}\leftarrow(ax_{i} + c) \bmod m @f$. |
* |
* The template parameter @p _UIntType must be an unsigned integral type |
* large enough to store values up to (__m-1). If the template parameter |
* @p __m is 0, the modulus @p __m used is |
* std::numeric_limits<_UIntType>::max() plus 1. Otherwise, the template |
* parameters @p __a and @p __c must be less than @p __m. |
* |
* The size of the state is @f$ 1 @f$. |
*/ |
template<class _UIntType, _UIntType __a, _UIntType __c, _UIntType __m> |
class linear_congruential |
{ |
__glibcxx_class_requires(_UIntType, _UnsignedIntegerConcept) |
// __glibcpp_class_requires(__a < __m && __c < __m) |
|
public: |
/** The type of the generated random value. */ |
typedef _UIntType result_type; |
|
/** The multiplier. */ |
static const _UIntType multiplier = __a; |
/** An increment. */ |
static const _UIntType increment = __c; |
/** The modulus. */ |
static const _UIntType modulus = __m; |
|
/** |
* Constructs a %linear_congruential random number generator engine with |
* seed @p __s. The default seed value is 1. |
* |
* @param __s The initial seed value. |
*/ |
explicit |
linear_congruential(unsigned long __x0 = 1) |
{ this->seed(__x0); } |
|
/** |
* Constructs a %linear_congruential random number generator engine |
* seeded from the generator function @p __g. |
* |
* @param __g The seed generator function. |
*/ |
template<class _Gen> |
linear_congruential(_Gen& __g) |
{ this->seed(__g); } |
|
/** |
* Reseeds the %linear_congruential random number generator engine |
* sequence to the seed @g __s. |
* |
* @param __s The new seed. |
*/ |
void |
seed(unsigned long __s = 1); |
|
/** |
* Reseeds the %linear_congruential random number generator engine |
* sequence using values from the generator function @p __g. |
* |
* @param __g the seed generator function. |
*/ |
template<class _Gen> |
void |
seed(_Gen& __g) |
{ seed(__g, typename is_fundamental<_Gen>::type()); } |
|
/** |
* Gets the smallest possible value in the output range. |
* |
* The minimum depends on the @p __c parameter: if it is zero, the |
* minimum generated must be > 0, otherwise 0 is allowed. |
*/ |
result_type |
min() const |
{ return (__detail::__mod<_UIntType, 1, 0, __m>(__c) == 0) ? 1 : 0; } |
|
/** |
* Gets the largest possible value in the output range. |
*/ |
result_type |
max() const |
{ return __m - 1; } |
|
/** |
* Gets the next random number in the sequence. |
*/ |
result_type |
operator()(); |
|
/** |
* Compares two linear congruential random number generator |
* objects of the same type for equality. |
* |
* @param __lhs A linear congruential random number generator object. |
* @param __rhs Another linear congruential random number generator obj. |
* |
* @returns true if the two objects are equal, false otherwise. |
*/ |
friend bool |
operator==(const linear_congruential& __lhs, |
const linear_congruential& __rhs) |
{ return __lhs._M_x == __rhs._M_x; } |
|
/** |
* Compares two linear congruential random number generator |
* objects of the same type for inequality. |
* |
* @param __lhs A linear congruential random number generator object. |
* @param __rhs Another linear congruential random number generator obj. |
* |
* @returns true if the two objects are not equal, false otherwise. |
*/ |
friend bool |
operator!=(const linear_congruential& __lhs, |
const linear_congruential& __rhs) |
{ return !(__lhs == __rhs); } |
|
/** |
* Writes the textual representation of the state x(i) of x to @p __os. |
* |
* @param __os The output stream. |
* @param __lcr A % linear_congruential random number generator. |
* @returns __os. |
*/ |
template<class _UIntType1, _UIntType1 __a1, _UIntType1 __c1, |
_UIntType1 __m1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const linear_congruential<_UIntType1, __a1, __c1, |
__m1>& __lcr); |
|
/** |
* Sets the state of the engine by reading its textual |
* representation from @p __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 |
* @p __is. |
* |
* @param __is The input stream. |
* @param __lcr A % linear_congruential random number generator. |
* @returns __is. |
*/ |
template<class _UIntType1, _UIntType1 __a1, _UIntType1 __c1, |
_UIntType1 __m1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
linear_congruential<_UIntType1, __a1, __c1, __m1>& __lcr); |
|
private: |
template<class _Gen> |
void |
seed(_Gen& __g, true_type) |
{ return seed(static_cast<unsigned long>(__g)); } |
|
template<class _Gen> |
void |
seed(_Gen& __g, false_type); |
|
_UIntType _M_x; |
}; |
|
/** |
* The classic Minimum Standard rand0 of Lewis, Goodman, and Miller. |
*/ |
typedef linear_congruential<unsigned long, 16807, 0, 2147483647> minstd_rand0; |
|
/** |
* An alternative LCR (Lehmer Generator function) . |
*/ |
typedef linear_congruential<unsigned long, 48271, 0, 2147483647> minstd_rand; |
|
|
/** |
* A generalized feedback shift register discrete random number generator. |
* |
* This algorithm avoids multiplication and division and is designed to be |
* friendly to a pipelined architecture. If the parameters are chosen |
* correctly, this generator will produce numbers with a very long period and |
* fairly good apparent entropy, although still not cryptographically strong. |
* |
* The best way to use this generator is with the predefined mt19937 class. |
* |
* This algorithm was originally invented by Makoto Matsumoto and |
* Takuji Nishimura. |
* |
* @var word_size The number of bits in each element of the state vector. |
* @var state_size The degree of recursion. |
* @var shift_size The period parameter. |
* @var mask_bits The separation point bit index. |
* @var parameter_a The last row of the twist matrix. |
* @var output_u The first right-shift tempering matrix parameter. |
* @var output_s The first left-shift tempering matrix parameter. |
* @var output_b The first left-shift tempering matrix mask. |
* @var output_t The second left-shift tempering matrix parameter. |
* @var output_c The second left-shift tempering matrix mask. |
* @var output_l The second right-shift tempering matrix parameter. |
*/ |
template<class _UIntType, int __w, int __n, int __m, int __r, |
_UIntType __a, int __u, int __s, _UIntType __b, int __t, |
_UIntType __c, int __l> |
class mersenne_twister |
{ |
__glibcxx_class_requires(_UIntType, _UnsignedIntegerConcept) |
|
public: |
// types |
typedef _UIntType result_type; |
|
// parameter values |
static const int word_size = __w; |
static const int state_size = __n; |
static const int shift_size = __m; |
static const int mask_bits = __r; |
static const _UIntType parameter_a = __a; |
static const int output_u = __u; |
static const int output_s = __s; |
static const _UIntType output_b = __b; |
static const int output_t = __t; |
static const _UIntType output_c = __c; |
static const int output_l = __l; |
|
// constructors and member function |
mersenne_twister() |
{ seed(); } |
|
explicit |
mersenne_twister(unsigned long __value) |
{ seed(__value); } |
|
template<class _Gen> |
mersenne_twister(_Gen& __g) |
{ seed(__g); } |
|
void |
seed() |
{ seed(5489UL); } |
|
void |
seed(unsigned long __value); |
|
template<class _Gen> |
void |
seed(_Gen& __g) |
{ seed(__g, typename is_fundamental<_Gen>::type()); } |
|
result_type |
min() const |
{ return 0; }; |
|
result_type |
max() const |
{ return __detail::_Shift<_UIntType, __w>::__value - 1; } |
|
result_type |
operator()(); |
|
/** |
* Compares two % mersenne_twister random number generator objects of |
* the same type for equality. |
* |
* @param __lhs A % mersenne_twister random number generator object. |
* @param __rhs Another % mersenne_twister random number generator |
* object. |
* |
* @returns true if the two objects are equal, false otherwise. |
*/ |
friend bool |
operator==(const mersenne_twister& __lhs, |
const mersenne_twister& __rhs) |
{ return std::equal(__lhs._M_x, __lhs._M_x + state_size, __rhs._M_x); } |
|
/** |
* Compares two % mersenne_twister random number generator objects of |
* the same type for inequality. |
* |
* @param __lhs A % mersenne_twister random number generator object. |
* @param __rhs Another % mersenne_twister random number generator |
* object. |
* |
* @returns true if the two objects are not equal, false otherwise. |
*/ |
friend bool |
operator!=(const mersenne_twister& __lhs, |
const mersenne_twister& __rhs) |
{ return !(__lhs == __rhs); } |
|
/** |
* Inserts the current state of a % mersenne_twister random number |
* generator engine @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A % mersenne_twister random number generator engine. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<class _UIntType1, int __w1, int __n1, int __m1, int __r1, |
_UIntType1 __a1, int __u1, int __s1, _UIntType1 __b1, int __t1, |
_UIntType1 __c1, int __l1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const mersenne_twister<_UIntType1, __w1, __n1, __m1, __r1, |
__a1, __u1, __s1, __b1, __t1, __c1, __l1>& __x); |
|
/** |
* Extracts the current state of a % mersenne_twister random number |
* generator engine @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A % mersenne_twister random number generator engine. |
* |
* @returns The input stream with the state of @p __x extracted or in |
* an error state. |
*/ |
template<class _UIntType1, int __w1, int __n1, int __m1, int __r1, |
_UIntType1 __a1, int __u1, int __s1, _UIntType1 __b1, int __t1, |
_UIntType1 __c1, int __l1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
mersenne_twister<_UIntType1, __w1, __n1, __m1, __r1, |
__a1, __u1, __s1, __b1, __t1, __c1, __l1>& __x); |
|
private: |
template<class _Gen> |
void |
seed(_Gen& __g, true_type) |
{ return seed(static_cast<unsigned long>(__g)); } |
|
template<class _Gen> |
void |
seed(_Gen& __g, false_type); |
|
_UIntType _M_x[state_size]; |
int _M_p; |
}; |
|
/** |
* The classic Mersenne Twister. |
* |
* Reference: |
* M. Matsumoto and T. Nishimura, Mersenne Twister: A 623-Dimensionally |
* Equidistributed Uniform Pseudo-Random Number Generator, ACM Transactions |
* on Modeling and Computer Simulation, Vol. 8, No. 1, January 1998, pp 3-30. |
*/ |
typedef mersenne_twister< |
unsigned long, 32, 624, 397, 31, |
0x9908b0dful, 11, 7, |
0x9d2c5680ul, 15, |
0xefc60000ul, 18 |
> mt19937; |
|
|
/** |
* @brief The Marsaglia-Zaman generator. |
* |
* This is a model of a Generalized Fibonacci discrete random number |
* generator, sometimes referred to as the SWC generator. |
* |
* A discrete random number generator that produces pseudorandom |
* numbers using @f$x_{i}\leftarrow(x_{i - s} - x_{i - r} - |
* carry_{i-1}) \bmod m @f$. |
* |
* The size of the state is @f$ r @f$ |
* and the maximum period of the generator is @f$ m^r - m^s -1 @f$. |
* |
* N1688[4.13] says <em>the template parameter _IntType shall denote |
* an integral type large enough to store values up to m</em>. |
* |
* @var _M_x The state of the generator. This is a ring buffer. |
* @var _M_carry The carry. |
* @var _M_p Current index of x(i - r). |
*/ |
template<typename _IntType, _IntType __m, int __s, int __r> |
class subtract_with_carry |
{ |
__glibcxx_class_requires(_IntType, _IntegerConcept) |
|
public: |
/** The type of the generated random value. */ |
typedef _IntType result_type; |
|
// parameter values |
static const _IntType modulus = __m; |
static const int long_lag = __r; |
static const int short_lag = __s; |
|
/** |
* Constructs a default-initialized % subtract_with_carry random number |
* generator. |
*/ |
subtract_with_carry() |
{ this->seed(); } |
|
/** |
* Constructs an explicitly seeded % subtract_with_carry random number |
* generator. |
*/ |
explicit |
subtract_with_carry(unsigned long __value) |
{ this->seed(__value); } |
|
/** |
* Constructs a %subtract_with_carry random number generator engine |
* seeded from the generator function @p __g. |
* |
* @param __g The seed generator function. |
*/ |
template<class _Gen> |
subtract_with_carry(_Gen& __g) |
{ this->seed(__g); } |
|
/** |
* Seeds the initial state @f$ x_0 @f$ of the random number generator. |
* |
* N1688[4.19] modifies this as follows. If @p __value == 0, |
* sets value to 19780503. In any case, with a linear |
* congruential generator lcg(i) having parameters @f$ m_{lcg} = |
* 2147483563, a_{lcg} = 40014, c_{lcg} = 0, and lcg(0) = value |
* @f$, sets @f$ x_{-r} \dots x_{-1} @f$ to @f$ lcg(1) \bmod m |
* \dots lcg(r) \bmod m @f$ respectively. If @f$ x_{-1} = 0 @f$ |
* set carry to 1, otherwise sets carry to 0. |
*/ |
void |
seed(unsigned long __value = 19780503); |
|
/** |
* Seeds the initial state @f$ x_0 @f$ of the % subtract_with_carry |
* random number generator. |
*/ |
template<class _Gen> |
void |
seed(_Gen& __g) |
{ seed(__g, typename is_fundamental<_Gen>::type()); } |
|
/** |
* Gets the inclusive minimum value of the range of random integers |
* returned by this generator. |
*/ |
result_type |
min() const |
{ return 0; } |
|
/** |
* Gets the inclusive maximum value of the range of random integers |
* returned by this generator. |
*/ |
result_type |
max() const |
{ return this->modulus - 1; } |
|
/** |
* Gets the next random number in the sequence. |
*/ |
result_type |
operator()(); |
|
/** |
* Compares two % subtract_with_carry random number generator objects of |
* the same type for equality. |
* |
* @param __lhs A % subtract_with_carry random number generator object. |
* @param __rhs Another % subtract_with_carry random number generator |
* object. |
* |
* @returns true if the two objects are equal, false otherwise. |
*/ |
friend bool |
operator==(const subtract_with_carry& __lhs, |
const subtract_with_carry& __rhs) |
{ return std::equal(__lhs._M_x, __lhs._M_x + long_lag, __rhs._M_x); } |
|
/** |
* Compares two % subtract_with_carry random number generator objects of |
* the same type for inequality. |
* |
* @param __lhs A % subtract_with_carry random number generator object. |
* @param __rhs Another % subtract_with_carry random number generator |
* object. |
* |
* @returns true if the two objects are not equal, false otherwise. |
*/ |
friend bool |
operator!=(const subtract_with_carry& __lhs, |
const subtract_with_carry& __rhs) |
{ return !(__lhs == __rhs); } |
|
/** |
* Inserts the current state of a % subtract_with_carry random number |
* generator engine @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A % subtract_with_carry random number generator engine. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _IntType1, _IntType1 __m1, int __s1, int __r1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const subtract_with_carry<_IntType1, __m1, __s1, |
__r1>& __x); |
|
/** |
* Extracts the current state of a % subtract_with_carry random number |
* generator engine @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A % subtract_with_carry random number generator engine. |
* |
* @returns The input stream with the state of @p __x extracted or in |
* an error state. |
*/ |
template<typename _IntType1, _IntType1 __m1, int __s1, int __r1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
subtract_with_carry<_IntType1, __m1, __s1, __r1>& __x); |
|
private: |
template<class _Gen> |
void |
seed(_Gen& __g, true_type) |
{ return seed(static_cast<unsigned long>(__g)); } |
|
template<class _Gen> |
void |
seed(_Gen& __g, false_type); |
|
typedef typename __gnu_cxx::__add_unsigned<_IntType>::__type _UIntType; |
|
_UIntType _M_x[long_lag]; |
_UIntType _M_carry; |
int _M_p; |
}; |
|
|
/** |
* @brief The Marsaglia-Zaman generator (floats version). |
* |
* @var _M_x The state of the generator. This is a ring buffer. |
* @var _M_carry The carry. |
* @var _M_p Current index of x(i - r). |
* @var _M_npows Precomputed negative powers of 2. |
*/ |
template<typename _RealType, int __w, int __s, int __r> |
class subtract_with_carry_01 |
{ |
public: |
/** The type of the generated random value. */ |
typedef _RealType result_type; |
|
// parameter values |
static const int word_size = __w; |
static const int long_lag = __r; |
static const int short_lag = __s; |
|
/** |
* Constructs a default-initialized % subtract_with_carry_01 random |
* number generator. |
*/ |
subtract_with_carry_01() |
{ |
this->seed(); |
_M_initialize_npows(); |
} |
|
/** |
* Constructs an explicitly seeded % subtract_with_carry_01 random number |
* generator. |
*/ |
explicit |
subtract_with_carry_01(unsigned long __value) |
{ |
this->seed(__value); |
_M_initialize_npows(); |
} |
|
/** |
* Constructs a % subtract_with_carry_01 random number generator engine |
* seeded from the generator function @p __g. |
* |
* @param __g The seed generator function. |
*/ |
template<class _Gen> |
subtract_with_carry_01(_Gen& __g) |
{ |
this->seed(__g); |
_M_initialize_npows(); |
} |
|
/** |
* Seeds the initial state @f$ x_0 @f$ of the random number generator. |
*/ |
void |
seed(unsigned long __value = 19780503); |
|
/** |
* Seeds the initial state @f$ x_0 @f$ of the % subtract_with_carry_01 |
* random number generator. |
*/ |
template<class _Gen> |
void |
seed(_Gen& __g) |
{ seed(__g, typename is_fundamental<_Gen>::type()); } |
|
/** |
* Gets the minimum value of the range of random floats |
* returned by this generator. |
*/ |
result_type |
min() const |
{ return 0.0; } |
|
/** |
* Gets the maximum value of the range of random floats |
* returned by this generator. |
*/ |
result_type |
max() const |
{ return 1.0; } |
|
/** |
* Gets the next random number in the sequence. |
*/ |
result_type |
operator()(); |
|
/** |
* Compares two % subtract_with_carry_01 random number generator objects |
* of the same type for equality. |
* |
* @param __lhs A % subtract_with_carry_01 random number |
* generator object. |
* @param __rhs Another % subtract_with_carry_01 random number generator |
* object. |
* |
* @returns true if the two objects are equal, false otherwise. |
*/ |
friend bool |
operator==(const subtract_with_carry_01& __lhs, |
const subtract_with_carry_01& __rhs) |
{ |
for (int __i = 0; __i < long_lag; ++__i) |
if (!std::equal(__lhs._M_x[__i], __lhs._M_x[__i] + __n, |
__rhs._M_x[__i])) |
return false; |
return true; |
} |
|
/** |
* Compares two % subtract_with_carry_01 random number generator objects |
* of the same type for inequality. |
* |
* @param __lhs A % subtract_with_carry_01 random number |
* generator object. |
* |
* @param __rhs Another % subtract_with_carry_01 random number generator |
* object. |
* |
* @returns true if the two objects are not equal, false otherwise. |
*/ |
friend bool |
operator!=(const subtract_with_carry_01& __lhs, |
const subtract_with_carry_01& __rhs) |
{ return !(__lhs == __rhs); } |
|
/** |
* Inserts the current state of a % subtract_with_carry_01 random number |
* generator engine @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A % subtract_with_carry_01 random number generator engine. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _RealType1, int __w1, int __s1, int __r1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const subtract_with_carry_01<_RealType1, __w1, __s1, |
__r1>& __x); |
|
/** |
* Extracts the current state of a % subtract_with_carry_01 random number |
* generator engine @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A % subtract_with_carry_01 random number generator engine. |
* |
* @returns The input stream with the state of @p __x extracted or in |
* an error state. |
*/ |
template<typename _RealType1, int __w1, int __s1, int __r1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
subtract_with_carry_01<_RealType1, __w1, __s1, __r1>& __x); |
|
private: |
template<class _Gen> |
void |
seed(_Gen& __g, true_type) |
{ return seed(static_cast<unsigned long>(__g)); } |
|
template<class _Gen> |
void |
seed(_Gen& __g, false_type); |
|
void |
_M_initialize_npows(); |
|
static const int __n = (__w + 31) / 32; |
|
typedef __detail::_UInt32Type _UInt32Type; |
_UInt32Type _M_x[long_lag][__n]; |
_RealType _M_npows[__n]; |
_UInt32Type _M_carry; |
int _M_p; |
}; |
|
typedef subtract_with_carry_01<float, 24, 10, 24> ranlux_base_01; |
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS |
// 508. Bad parameters for ranlux64_base_01. |
typedef subtract_with_carry_01<double, 48, 5, 12> ranlux64_base_01; |
|
|
/** |
* Produces random numbers from some base engine by discarding blocks of |
* data. |
* |
* 0 <= @p __r <= @p __p |
*/ |
template<class _UniformRandomNumberGenerator, int __p, int __r> |
class discard_block |
{ |
// __glibcxx_class_requires(typename base_type::result_type, |
// ArithmeticTypeConcept) |
|
public: |
/** The type of the underlying generator engine. */ |
typedef _UniformRandomNumberGenerator base_type; |
/** The type of the generated random value. */ |
typedef typename base_type::result_type result_type; |
|
// parameter values |
static const int block_size = __p; |
static const int used_block = __r; |
|
/** |
* Constructs a default %discard_block engine. |
* |
* The underlying engine is default constructed as well. |
*/ |
discard_block() |
: _M_n(0) { } |
|
/** |
* Copy constructs a %discard_block engine. |
* |
* Copies an existing base class random number generator. |
* @param rng An existing (base class) engine object. |
*/ |
explicit |
discard_block(const base_type& __rng) |
: _M_b(__rng), _M_n(0) { } |
|
/** |
* Seed constructs a %discard_block engine. |
* |
* Constructs the underlying generator engine seeded with @p __s. |
* @param __s A seed value for the base class engine. |
*/ |
explicit |
discard_block(unsigned long __s) |
: _M_b(__s), _M_n(0) { } |
|
/** |
* Generator construct a %discard_block engine. |
* |
* @param __g A seed generator function. |
*/ |
template<class _Gen> |
discard_block(_Gen& __g) |
: _M_b(__g), _M_n(0) { } |
|
/** |
* Reseeds the %discard_block object with the default seed for the |
* underlying base class generator engine. |
*/ |
void seed() |
{ |
_M_b.seed(); |
_M_n = 0; |
} |
|
/** |
* Reseeds the %discard_block object with the given seed generator |
* function. |
* @param __g A seed generator function. |
*/ |
template<class _Gen> |
void seed(_Gen& __g) |
{ |
_M_b.seed(__g); |
_M_n = 0; |
} |
|
/** |
* Gets a const reference to the underlying generator engine object. |
*/ |
const base_type& |
base() const |
{ return _M_b; } |
|
/** |
* Gets the minimum value in the generated random number range. |
*/ |
result_type |
min() const |
{ return _M_b.min(); } |
|
/** |
* Gets the maximum value in the generated random number range. |
*/ |
result_type |
max() const |
{ return _M_b.max(); } |
|
/** |
* Gets the next value in the generated random number sequence. |
*/ |
result_type |
operator()(); |
|
/** |
* Compares two %discard_block random number generator objects of |
* the same type for equality. |
* |
* @param __lhs A %discard_block random number generator object. |
* @param __rhs Another %discard_block random number generator |
* object. |
* |
* @returns true if the two objects are equal, false otherwise. |
*/ |
friend bool |
operator==(const discard_block& __lhs, const discard_block& __rhs) |
{ return (__lhs._M_b == __rhs._M_b) && (__lhs._M_n == __rhs._M_n); } |
|
/** |
* Compares two %discard_block random number generator objects of |
* the same type for inequality. |
* |
* @param __lhs A %discard_block random number generator object. |
* @param __rhs Another %discard_block random number generator |
* object. |
* |
* @returns true if the two objects are not equal, false otherwise. |
*/ |
friend bool |
operator!=(const discard_block& __lhs, const discard_block& __rhs) |
{ return !(__lhs == __rhs); } |
|
/** |
* Inserts the current state of a %discard_block random number |
* generator engine @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %discard_block random number generator engine. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<class _UniformRandomNumberGenerator1, int __p1, int __r1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const discard_block<_UniformRandomNumberGenerator1, |
__p1, __r1>& __x); |
|
/** |
* Extracts the current state of a % subtract_with_carry random number |
* generator engine @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %discard_block random number generator engine. |
* |
* @returns The input stream with the state of @p __x extracted or in |
* an error state. |
*/ |
template<class _UniformRandomNumberGenerator1, int __p1, int __r1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
discard_block<_UniformRandomNumberGenerator1, |
__p1, __r1>& __x); |
|
private: |
base_type _M_b; |
int _M_n; |
}; |
|
|
/** |
* James's luxury-level-3 integer adaptation of Luescher's generator. |
*/ |
typedef discard_block< |
subtract_with_carry<unsigned long, (1UL << 24), 10, 24>, |
223, |
24 |
> ranlux3; |
|
/** |
* James's luxury-level-4 integer adaptation of Luescher's generator. |
*/ |
typedef discard_block< |
subtract_with_carry<unsigned long, (1UL << 24), 10, 24>, |
389, |
24 |
> ranlux4; |
|
typedef discard_block< |
subtract_with_carry_01<float, 24, 10, 24>, |
223, |
24 |
> ranlux3_01; |
|
typedef discard_block< |
subtract_with_carry_01<float, 24, 10, 24>, |
389, |
24 |
> ranlux4_01; |
|
|
/** |
* A random number generator adaptor class that combines two random number |
* generator engines into a single output sequence. |
*/ |
template<class _UniformRandomNumberGenerator1, int __s1, |
class _UniformRandomNumberGenerator2, int __s2> |
class xor_combine |
{ |
// __glibcxx_class_requires(typename _UniformRandomNumberGenerator1:: |
// result_type, ArithmeticTypeConcept) |
// __glibcxx_class_requires(typename _UniformRandomNumberGenerator2:: |
// result_type, ArithmeticTypeConcept) |
|
public: |
/** The type of the first underlying generator engine. */ |
typedef _UniformRandomNumberGenerator1 base1_type; |
/** The type of the second underlying generator engine. */ |
typedef _UniformRandomNumberGenerator2 base2_type; |
|
private: |
typedef typename base1_type::result_type _Result_type1; |
typedef typename base2_type::result_type _Result_type2; |
|
public: |
/** The type of the generated random value. */ |
typedef typename __gnu_cxx::__conditional_type<(sizeof(_Result_type1) |
> sizeof(_Result_type2)), |
_Result_type1, _Result_type2>::__type result_type; |
|
// parameter values |
static const int shift1 = __s1; |
static const int shift2 = __s2; |
|
// constructors and member function |
xor_combine() |
: _M_b1(), _M_b2() |
{ _M_initialize_max(); } |
|
xor_combine(const base1_type& __rng1, const base2_type& __rng2) |
: _M_b1(__rng1), _M_b2(__rng2) |
{ _M_initialize_max(); } |
|
xor_combine(unsigned long __s) |
: _M_b1(__s), _M_b2(__s + 1) |
{ _M_initialize_max(); } |
|
template<class _Gen> |
xor_combine(_Gen& __g) |
: _M_b1(__g), _M_b2(__g) |
{ _M_initialize_max(); } |
|
void |
seed() |
{ |
_M_b1.seed(); |
_M_b2.seed(); |
} |
|
template<class _Gen> |
void |
seed(_Gen& __g) |
{ |
_M_b1.seed(__g); |
_M_b2.seed(__g); |
} |
|
const base1_type& |
base1() const |
{ return _M_b1; } |
|
const base2_type& |
base2() const |
{ return _M_b2; } |
|
result_type |
min() const |
{ return 0; } |
|
result_type |
max() const |
{ return _M_max; } |
|
/** |
* Gets the next random number in the sequence. |
*/ |
// NB: Not exactly the TR1 formula, per N2079 instead. |
result_type |
operator()() |
{ |
return ((result_type(_M_b1() - _M_b1.min()) << shift1) |
^ (result_type(_M_b2() - _M_b2.min()) << shift2)); |
} |
|
/** |
* Compares two %xor_combine random number generator objects of |
* the same type for equality. |
* |
* @param __lhs A %xor_combine random number generator object. |
* @param __rhs Another %xor_combine random number generator |
* object. |
* |
* @returns true if the two objects are equal, false otherwise. |
*/ |
friend bool |
operator==(const xor_combine& __lhs, const xor_combine& __rhs) |
{ |
return (__lhs.base1() == __rhs.base1()) |
&& (__lhs.base2() == __rhs.base2()); |
} |
|
/** |
* Compares two %xor_combine random number generator objects of |
* the same type for inequality. |
* |
* @param __lhs A %xor_combine random number generator object. |
* @param __rhs Another %xor_combine random number generator |
* object. |
* |
* @returns true if the two objects are not equal, false otherwise. |
*/ |
friend bool |
operator!=(const xor_combine& __lhs, const xor_combine& __rhs) |
{ return !(__lhs == __rhs); } |
|
/** |
* Inserts the current state of a %xor_combine random number |
* generator engine @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %xor_combine random number generator engine. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<class _UniformRandomNumberGenerator11, int __s11, |
class _UniformRandomNumberGenerator21, int __s21, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const xor_combine<_UniformRandomNumberGenerator11, __s11, |
_UniformRandomNumberGenerator21, __s21>& __x); |
|
/** |
* Extracts the current state of a %xor_combine random number |
* generator engine @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %xor_combine random number generator engine. |
* |
* @returns The input stream with the state of @p __x extracted or in |
* an error state. |
*/ |
template<class _UniformRandomNumberGenerator11, int __s11, |
class _UniformRandomNumberGenerator21, int __s21, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
xor_combine<_UniformRandomNumberGenerator11, __s11, |
_UniformRandomNumberGenerator21, __s21>& __x); |
|
private: |
void |
_M_initialize_max(); |
|
result_type |
_M_initialize_max_aux(result_type, result_type, int); |
|
base1_type _M_b1; |
base2_type _M_b2; |
result_type _M_max; |
}; |
|
|
/** |
* A standard interface to a platform-specific non-deterministic |
* random number generator (if any are available). |
*/ |
class random_device |
{ |
public: |
// types |
typedef unsigned int result_type; |
|
// constructors, destructors and member functions |
|
#ifdef _GLIBCXX_USE_RANDOM_TR1 |
|
explicit |
random_device(const std::string& __token = "/dev/urandom") |
{ |
if ((__token != "/dev/urandom" && __token != "/dev/random") |
|| !(_M_file = std::fopen(__token.c_str(), "rb"))) |
std::__throw_runtime_error(__N("random_device::" |
"random_device(const std::string&)")); |
} |
|
~random_device() |
{ std::fclose(_M_file); } |
|
#else |
|
explicit |
random_device(const std::string& __token = "mt19937") |
: _M_mt(_M_strtoul(__token)) { } |
|
private: |
static unsigned long |
_M_strtoul(const std::string& __str) |
{ |
unsigned long __ret = 5489UL; |
if (__str != "mt19937") |
{ |
const char* __nptr = __str.c_str(); |
char* __endptr; |
__ret = std::strtoul(__nptr, &__endptr, 0); |
if (*__nptr == '\0' || *__endptr != '\0') |
std::__throw_runtime_error(__N("random_device::_M_strtoul" |
"(const std::string&)")); |
} |
return __ret; |
} |
|
public: |
|
#endif |
|
result_type |
min() const |
{ return std::numeric_limits<result_type>::min(); } |
|
result_type |
max() const |
{ return std::numeric_limits<result_type>::max(); } |
|
double |
entropy() const |
{ return 0.0; } |
|
result_type |
operator()() |
{ |
#ifdef _GLIBCXX_USE_RANDOM_TR1 |
result_type __ret; |
std::fread(reinterpret_cast<void*>(&__ret), sizeof(result_type), |
1, _M_file); |
return __ret; |
#else |
return _M_mt(); |
#endif |
} |
|
private: |
random_device(const random_device&); |
void operator=(const random_device&); |
|
#ifdef _GLIBCXX_USE_RANDOM_TR1 |
FILE* _M_file; |
#else |
mt19937 _M_mt; |
#endif |
}; |
|
/* @} */ // group tr1_random_generators |
|
/** |
* @addtogroup tr1_random_distributions Random Number Distributions |
* @ingroup tr1_random |
* @{ |
*/ |
|
/** |
* @addtogroup tr1_random_distributions_discrete Discrete Distributions |
* @ingroup tr1_random_distributions |
* @{ |
*/ |
|
/** |
* @brief Uniform discrete distribution for random numbers. |
* A discrete random distribution on the range @f$[min, max]@f$ with equal |
* probability throughout the range. |
*/ |
template<typename _IntType = int> |
class uniform_int |
{ |
__glibcxx_class_requires(_IntType, _IntegerConcept) |
|
public: |
/** The type of the parameters of the distribution. */ |
typedef _IntType input_type; |
/** The type of the range of the distribution. */ |
typedef _IntType result_type; |
|
public: |
/** |
* Constructs a uniform distribution object. |
*/ |
explicit |
uniform_int(_IntType __min = 0, _IntType __max = 9) |
: _M_min(__min), _M_max(__max) |
{ |
_GLIBCXX_DEBUG_ASSERT(_M_min <= _M_max); |
} |
|
/** |
* Gets the inclusive lower bound of the distribution range. |
*/ |
result_type |
min() const |
{ return _M_min; } |
|
/** |
* Gets the inclusive upper bound of the distribution range. |
*/ |
result_type |
max() const |
{ return _M_max; } |
|
/** |
* Resets the distribution state. |
* |
* Does nothing for the uniform integer distribution. |
*/ |
void |
reset() { } |
|
/** |
* Gets a uniformly distributed random number in the range |
* @f$(min, max)@f$. |
*/ |
template<typename _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng) |
{ |
typedef typename _UniformRandomNumberGenerator::result_type |
_UResult_type; |
return _M_call(__urng, _M_min, _M_max, |
typename is_integral<_UResult_type>::type()); |
} |
|
/** |
* Gets a uniform random number in the range @f$[0, n)@f$. |
* |
* This function is aimed at use with std::random_shuffle. |
*/ |
template<typename _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng, result_type __n) |
{ |
typedef typename _UniformRandomNumberGenerator::result_type |
_UResult_type; |
return _M_call(__urng, 0, __n - 1, |
typename is_integral<_UResult_type>::type()); |
} |
|
/** |
* Inserts a %uniform_int random number distribution @p __x into the |
* output stream @p os. |
* |
* @param __os An output stream. |
* @param __x A %uniform_int random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _IntType1, typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const uniform_int<_IntType1>& __x); |
|
/** |
* Extracts a %uniform_int random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %uniform_int random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _IntType1, typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
uniform_int<_IntType1>& __x); |
|
private: |
template<typename _UniformRandomNumberGenerator> |
result_type |
_M_call(_UniformRandomNumberGenerator& __urng, |
result_type __min, result_type __max, true_type); |
|
template<typename _UniformRandomNumberGenerator> |
result_type |
_M_call(_UniformRandomNumberGenerator& __urng, |
result_type __min, result_type __max, false_type) |
{ |
return result_type((__urng() - __urng.min()) |
/ (__urng.max() - __urng.min()) |
* (__max - __min + 1)) + __min; |
} |
|
_IntType _M_min; |
_IntType _M_max; |
}; |
|
|
/** |
* @brief A Bernoulli random number distribution. |
* |
* Generates a sequence of true and false values with likelihood @f$ p @f$ |
* that true will come up and @f$ (1 - p) @f$ that false will appear. |
*/ |
class bernoulli_distribution |
{ |
public: |
typedef int input_type; |
typedef bool result_type; |
|
public: |
/** |
* Constructs a Bernoulli distribution with likelihood @p p. |
* |
* @param __p [IN] The likelihood of a true result being returned. Must |
* be in the interval @f$ [0, 1] @f$. |
*/ |
explicit |
bernoulli_distribution(double __p = 0.5) |
: _M_p(__p) |
{ |
_GLIBCXX_DEBUG_ASSERT((_M_p >= 0.0) && (_M_p <= 1.0)); |
} |
|
/** |
* Gets the @p p parameter of the distribution. |
*/ |
double |
p() const |
{ return _M_p; } |
|
/** |
* Resets the distribution state. |
* |
* Does nothing for a Bernoulli distribution. |
*/ |
void |
reset() { } |
|
/** |
* Gets the next value in the Bernoullian sequence. |
*/ |
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng) |
{ |
if ((__urng() - __urng.min()) < _M_p * (__urng.max() - __urng.min())) |
return true; |
return false; |
} |
|
/** |
* Inserts a %bernoulli_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %bernoulli_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const bernoulli_distribution& __x); |
|
/** |
* Extracts a %bernoulli_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %bernoulli_distribution random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
bernoulli_distribution& __x) |
{ return __is >> __x._M_p; } |
|
private: |
double _M_p; |
}; |
|
|
/** |
* @brief A discrete geometric random number distribution. |
* |
* The formula for the geometric probability mass function is |
* @f$ p(i) = (1 - p)p^{i-1} @f$ where @f$ p @f$ is the parameter of the |
* distribution. |
*/ |
template<typename _IntType = int, typename _RealType = double> |
class geometric_distribution |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _IntType result_type; |
|
// constructors and member function |
explicit |
geometric_distribution(const _RealType& __p = _RealType(0.5)) |
: _M_p(__p) |
{ |
_GLIBCXX_DEBUG_ASSERT((_M_p > 0.0) && (_M_p < 1.0)); |
_M_initialize(); |
} |
|
/** |
* Gets the distribution parameter @p p. |
*/ |
_RealType |
p() const |
{ return _M_p; } |
|
void |
reset() { } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng); |
|
/** |
* Inserts a %geometric_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %geometric_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _IntType1, typename _RealType1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const geometric_distribution<_IntType1, _RealType1>& __x); |
|
/** |
* Extracts a %geometric_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %geometric_distribution random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
geometric_distribution& __x) |
{ |
__is >> __x._M_p; |
__x._M_initialize(); |
return __is; |
} |
|
private: |
void |
_M_initialize() |
{ _M_log_p = std::log(_M_p); } |
|
_RealType _M_p; |
_RealType _M_log_p; |
}; |
|
|
template<typename _RealType> |
class normal_distribution; |
|
/** |
* @brief A discrete Poisson random number distribution. |
* |
* The formula for the Poisson probability mass function is |
* @f$ p(i) = \frac{mean^i}{i!} e^{-mean} @f$ where @f$ mean @f$ is the |
* parameter of the distribution. |
*/ |
template<typename _IntType = int, typename _RealType = double> |
class poisson_distribution |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _IntType result_type; |
|
// constructors and member function |
explicit |
poisson_distribution(const _RealType& __mean = _RealType(1)) |
: _M_mean(__mean), _M_nd() |
{ |
_GLIBCXX_DEBUG_ASSERT(_M_mean > 0.0); |
_M_initialize(); |
} |
|
/** |
* Gets the distribution parameter @p mean. |
*/ |
_RealType |
mean() const |
{ return _M_mean; } |
|
void |
reset() |
{ _M_nd.reset(); } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng); |
|
/** |
* Inserts a %poisson_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %poisson_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _IntType1, typename _RealType1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const poisson_distribution<_IntType1, _RealType1>& __x); |
|
/** |
* Extracts a %poisson_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %poisson_distribution random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _IntType1, typename _RealType1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
poisson_distribution<_IntType1, _RealType1>& __x); |
|
private: |
void |
_M_initialize(); |
|
// NB: Unused when _GLIBCXX_USE_C99_MATH_TR1 is undefined. |
normal_distribution<_RealType> _M_nd; |
|
_RealType _M_mean; |
|
// Hosts either log(mean) or the threshold of the simple method. |
_RealType _M_lm_thr; |
#if _GLIBCXX_USE_C99_MATH_TR1 |
_RealType _M_lfm, _M_sm, _M_d, _M_scx, _M_1cx, _M_c2b, _M_cb; |
#endif |
}; |
|
|
/** |
* @brief A discrete binomial random number distribution. |
* |
* The formula for the binomial probability mass function is |
* @f$ p(i) = \binom{n}{i} p^i (1 - p)^{t - i} @f$ where @f$ t @f$ |
* and @f$ p @f$ are the parameters of the distribution. |
*/ |
template<typename _IntType = int, typename _RealType = double> |
class binomial_distribution |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _IntType result_type; |
|
// constructors and member function |
explicit |
binomial_distribution(_IntType __t = 1, |
const _RealType& __p = _RealType(0.5)) |
: _M_t(__t), _M_p(__p), _M_nd() |
{ |
_GLIBCXX_DEBUG_ASSERT((_M_t >= 0) && (_M_p >= 0.0) && (_M_p <= 1.0)); |
_M_initialize(); |
} |
|
/** |
* Gets the distribution @p t parameter. |
*/ |
_IntType |
t() const |
{ return _M_t; } |
|
/** |
* Gets the distribution @p p parameter. |
*/ |
_RealType |
p() const |
{ return _M_p; } |
|
void |
reset() |
{ _M_nd.reset(); } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng); |
|
/** |
* Inserts a %binomial_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %binomial_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _IntType1, typename _RealType1, |
typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const binomial_distribution<_IntType1, _RealType1>& __x); |
|
/** |
* Extracts a %binomial_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %binomial_distribution random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _IntType1, typename _RealType1, |
typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
binomial_distribution<_IntType1, _RealType1>& __x); |
|
private: |
void |
_M_initialize(); |
|
template<class _UniformRandomNumberGenerator> |
result_type |
_M_waiting(_UniformRandomNumberGenerator& __urng, _IntType __t); |
|
// NB: Unused when _GLIBCXX_USE_C99_MATH_TR1 is undefined. |
normal_distribution<_RealType> _M_nd; |
|
_RealType _M_q; |
#if _GLIBCXX_USE_C99_MATH_TR1 |
_RealType _M_d1, _M_d2, _M_s1, _M_s2, _M_c, |
_M_a1, _M_a123, _M_s, _M_lf, _M_lp1p; |
#endif |
_RealType _M_p; |
_IntType _M_t; |
|
bool _M_easy; |
}; |
|
/* @} */ // group tr1_random_distributions_discrete |
|
/** |
* @addtogroup tr1_random_distributions_continuous Continuous Distributions |
* @ingroup tr1_random_distributions |
* @{ |
*/ |
|
/** |
* @brief Uniform continuous distribution for random numbers. |
* |
* A continuous random distribution on the range [min, max) with equal |
* probability throughout the range. The URNG should be real-valued and |
* deliver number in the range [0, 1). |
*/ |
template<typename _RealType = double> |
class uniform_real |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _RealType result_type; |
|
public: |
/** |
* Constructs a uniform_real object. |
* |
* @param __min [IN] The lower bound of the distribution. |
* @param __max [IN] The upper bound of the distribution. |
*/ |
explicit |
uniform_real(_RealType __min = _RealType(0), |
_RealType __max = _RealType(1)) |
: _M_min(__min), _M_max(__max) |
{ |
_GLIBCXX_DEBUG_ASSERT(_M_min <= _M_max); |
} |
|
result_type |
min() const |
{ return _M_min; } |
|
result_type |
max() const |
{ return _M_max; } |
|
void |
reset() { } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng) |
{ return (__urng() * (_M_max - _M_min)) + _M_min; } |
|
/** |
* Inserts a %uniform_real random number distribution @p __x into the |
* output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %uniform_real random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _RealType1, typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const uniform_real<_RealType1>& __x); |
|
/** |
* Extracts a %uniform_real random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %uniform_real random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _RealType1, typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
uniform_real<_RealType1>& __x); |
|
private: |
_RealType _M_min; |
_RealType _M_max; |
}; |
|
|
/** |
* @brief An exponential continuous distribution for random numbers. |
* |
* The formula for the exponential probability mass function is |
* @f$ p(x) = \lambda e^{-\lambda x} @f$. |
* |
* <table border=1 cellpadding=10 cellspacing=0> |
* <caption align=top>Distribution Statistics</caption> |
* <tr><td>Mean</td><td>@f$ \frac{1}{\lambda} @f$</td></tr> |
* <tr><td>Median</td><td>@f$ \frac{\ln 2}{\lambda} @f$</td></tr> |
* <tr><td>Mode</td><td>@f$ zero @f$</td></tr> |
* <tr><td>Range</td><td>@f$[0, \infty]@f$</td></tr> |
* <tr><td>Standard Deviation</td><td>@f$ \frac{1}{\lambda} @f$</td></tr> |
* </table> |
*/ |
template<typename _RealType = double> |
class exponential_distribution |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _RealType result_type; |
|
public: |
/** |
* Constructs an exponential distribution with inverse scale parameter |
* @f$ \lambda @f$. |
*/ |
explicit |
exponential_distribution(const result_type& __lambda = result_type(1)) |
: _M_lambda(__lambda) |
{ |
_GLIBCXX_DEBUG_ASSERT(_M_lambda > 0); |
} |
|
/** |
* Gets the inverse scale parameter of the distribution. |
*/ |
_RealType |
lambda() const |
{ return _M_lambda; } |
|
/** |
* Resets the distribution. |
* |
* Has no effect on exponential distributions. |
*/ |
void |
reset() { } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng) |
{ return -std::log(__urng()) / _M_lambda; } |
|
/** |
* Inserts a %exponential_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %exponential_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _RealType1, typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const exponential_distribution<_RealType1>& __x); |
|
/** |
* Extracts a %exponential_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %exponential_distribution random number |
* generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
exponential_distribution& __x) |
{ return __is >> __x._M_lambda; } |
|
private: |
result_type _M_lambda; |
}; |
|
|
/** |
* @brief A normal continuous distribution for random numbers. |
* |
* The formula for the normal probability mass function is |
* @f$ p(x) = \frac{1}{\sigma \sqrt{2 \pi}} |
* e^{- \frac{{x - mean}^ {2}}{2 \sigma ^ {2}} } @f$. |
*/ |
template<typename _RealType = double> |
class normal_distribution |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _RealType result_type; |
|
public: |
/** |
* Constructs a normal distribution with parameters @f$ mean @f$ and |
* @f$ \sigma @f$. |
*/ |
explicit |
normal_distribution(const result_type& __mean = result_type(0), |
const result_type& __sigma = result_type(1)) |
: _M_mean(__mean), _M_sigma(__sigma), _M_saved_available(false) |
{ |
_GLIBCXX_DEBUG_ASSERT(_M_sigma > 0); |
} |
|
/** |
* Gets the mean of the distribution. |
*/ |
_RealType |
mean() const |
{ return _M_mean; } |
|
/** |
* Gets the @f$ \sigma @f$ of the distribution. |
*/ |
_RealType |
sigma() const |
{ return _M_sigma; } |
|
/** |
* Resets the distribution. |
*/ |
void |
reset() |
{ _M_saved_available = false; } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng); |
|
/** |
* Inserts a %normal_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %normal_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _RealType1, typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const normal_distribution<_RealType1>& __x); |
|
/** |
* Extracts a %normal_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %normal_distribution random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _RealType1, typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
normal_distribution<_RealType1>& __x); |
|
private: |
result_type _M_mean; |
result_type _M_sigma; |
result_type _M_saved; |
bool _M_saved_available; |
}; |
|
|
/** |
* @brief A gamma continuous distribution for random numbers. |
* |
* The formula for the gamma probability mass function is |
* @f$ p(x) = \frac{1}{\Gamma(\alpha)} x^{\alpha - 1} e^{-x} @f$. |
*/ |
template<typename _RealType = double> |
class gamma_distribution |
{ |
public: |
// types |
typedef _RealType input_type; |
typedef _RealType result_type; |
|
public: |
/** |
* Constructs a gamma distribution with parameters @f$ \alpha @f$. |
*/ |
explicit |
gamma_distribution(const result_type& __alpha_val = result_type(1)) |
: _M_alpha(__alpha_val) |
{ |
_GLIBCXX_DEBUG_ASSERT(_M_alpha > 0); |
_M_initialize(); |
} |
|
/** |
* Gets the @f$ \alpha @f$ of the distribution. |
*/ |
_RealType |
alpha() const |
{ return _M_alpha; } |
|
/** |
* Resets the distribution. |
*/ |
void |
reset() { } |
|
template<class _UniformRandomNumberGenerator> |
result_type |
operator()(_UniformRandomNumberGenerator& __urng); |
|
/** |
* Inserts a %gamma_distribution random number distribution |
* @p __x into the output stream @p __os. |
* |
* @param __os An output stream. |
* @param __x A %gamma_distribution random number distribution. |
* |
* @returns The output stream with the state of @p __x inserted or in |
* an error state. |
*/ |
template<typename _RealType1, typename _CharT, typename _Traits> |
friend std::basic_ostream<_CharT, _Traits>& |
operator<<(std::basic_ostream<_CharT, _Traits>& __os, |
const gamma_distribution<_RealType1>& __x); |
|
/** |
* Extracts a %gamma_distribution random number distribution |
* @p __x from the input stream @p __is. |
* |
* @param __is An input stream. |
* @param __x A %gamma_distribution random number generator engine. |
* |
* @returns The input stream with @p __x extracted or in an error state. |
*/ |
template<typename _CharT, typename _Traits> |
friend std::basic_istream<_CharT, _Traits>& |
operator>>(std::basic_istream<_CharT, _Traits>& __is, |
gamma_distribution& __x) |
{ |
__is >> __x._M_alpha; |
__x._M_initialize(); |
return __is; |
} |
|
private: |
void |
_M_initialize(); |
|
result_type _M_alpha; |
|
// Hosts either lambda of GB or d of modified Vaduva's. |
result_type _M_l_d; |
}; |
|
/* @} */ // group tr1_random_distributions_continuous |
/* @} */ // group tr1_random_distributions |
/* @} */ // group tr1_random |
_GLIBCXX_END_NAMESPACE_VERSION |
} |
} |
|
#endif // _GLIBCXX_TR1_RANDOM_H |