| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP___RANDOM_FISHER_F_DISTRIBUTION_H |
| #define _LIBCPP___RANDOM_FISHER_F_DISTRIBUTION_H |
| |
| #include <__config> |
| #include <__random/gamma_distribution.h> |
| #include <iosfwd> |
| #include <limits> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| #pragma GCC system_header |
| #endif |
| |
| _LIBCPP_PUSH_MACROS |
| #include <__undef_macros> |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| template<class _RealType = double> |
| class _LIBCPP_TEMPLATE_VIS fisher_f_distribution |
| { |
| public: |
| // types |
| typedef _RealType result_type; |
| |
| class _LIBCPP_TEMPLATE_VIS param_type |
| { |
| result_type __m_; |
| result_type __n_; |
| public: |
| typedef fisher_f_distribution distribution_type; |
| |
| _LIBCPP_INLINE_VISIBILITY |
| explicit param_type(result_type __m = 1, result_type __n = 1) |
| : __m_(__m), __n_(__n) {} |
| |
| _LIBCPP_INLINE_VISIBILITY |
| result_type m() const {return __m_;} |
| _LIBCPP_INLINE_VISIBILITY |
| result_type n() const {return __n_;} |
| |
| friend _LIBCPP_INLINE_VISIBILITY |
| bool operator==(const param_type& __x, const param_type& __y) |
| {return __x.__m_ == __y.__m_ && __x.__n_ == __y.__n_;} |
| friend _LIBCPP_INLINE_VISIBILITY |
| bool operator!=(const param_type& __x, const param_type& __y) |
| {return !(__x == __y);} |
| }; |
| |
| private: |
| param_type __p_; |
| |
| public: |
| // constructor and reset functions |
| #ifndef _LIBCPP_CXX03_LANG |
| _LIBCPP_INLINE_VISIBILITY |
| fisher_f_distribution() : fisher_f_distribution(1) {} |
| _LIBCPP_INLINE_VISIBILITY |
| explicit fisher_f_distribution(result_type __m, result_type __n = 1) |
| : __p_(param_type(__m, __n)) {} |
| #else |
| _LIBCPP_INLINE_VISIBILITY |
| explicit fisher_f_distribution(result_type __m = 1, result_type __n = 1) |
| : __p_(param_type(__m, __n)) {} |
| #endif |
| _LIBCPP_INLINE_VISIBILITY |
| explicit fisher_f_distribution(const param_type& __p) |
| : __p_(__p) {} |
| _LIBCPP_INLINE_VISIBILITY |
| void reset() {} |
| |
| // generating functions |
| template<class _URNG> |
| _LIBCPP_INLINE_VISIBILITY |
| result_type operator()(_URNG& __g) |
| {return (*this)(__g, __p_);} |
| template<class _URNG> result_type operator()(_URNG& __g, const param_type& __p); |
| |
| // property functions |
| _LIBCPP_INLINE_VISIBILITY |
| result_type m() const {return __p_.m();} |
| _LIBCPP_INLINE_VISIBILITY |
| result_type n() const {return __p_.n();} |
| |
| _LIBCPP_INLINE_VISIBILITY |
| param_type param() const {return __p_;} |
| _LIBCPP_INLINE_VISIBILITY |
| void param(const param_type& __p) {__p_ = __p;} |
| |
| _LIBCPP_INLINE_VISIBILITY |
| result_type min() const {return 0;} |
| _LIBCPP_INLINE_VISIBILITY |
| result_type max() const {return numeric_limits<result_type>::infinity();} |
| |
| friend _LIBCPP_INLINE_VISIBILITY |
| bool operator==(const fisher_f_distribution& __x, |
| const fisher_f_distribution& __y) |
| {return __x.__p_ == __y.__p_;} |
| friend _LIBCPP_INLINE_VISIBILITY |
| bool operator!=(const fisher_f_distribution& __x, |
| const fisher_f_distribution& __y) |
| {return !(__x == __y);} |
| }; |
| |
| template <class _RealType> |
| template<class _URNG> |
| _RealType |
| fisher_f_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) |
| { |
| gamma_distribution<result_type> __gdm(__p.m() * result_type(.5)); |
| gamma_distribution<result_type> __gdn(__p.n() * result_type(.5)); |
| return __p.n() * __gdm(__g) / (__p.m() * __gdn(__g)); |
| } |
| |
| template <class _CharT, class _Traits, class _RT> |
| basic_ostream<_CharT, _Traits>& |
| operator<<(basic_ostream<_CharT, _Traits>& __os, |
| const fisher_f_distribution<_RT>& __x) |
| { |
| __save_flags<_CharT, _Traits> __lx(__os); |
| typedef basic_ostream<_CharT, _Traits> _OStream; |
| __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | |
| _OStream::scientific); |
| _CharT __sp = __os.widen(' '); |
| __os.fill(__sp); |
| __os << __x.m() << __sp << __x.n(); |
| return __os; |
| } |
| |
| template <class _CharT, class _Traits, class _RT> |
| basic_istream<_CharT, _Traits>& |
| operator>>(basic_istream<_CharT, _Traits>& __is, |
| fisher_f_distribution<_RT>& __x) |
| { |
| typedef fisher_f_distribution<_RT> _Eng; |
| typedef typename _Eng::result_type result_type; |
| typedef typename _Eng::param_type param_type; |
| __save_flags<_CharT, _Traits> __lx(__is); |
| typedef basic_istream<_CharT, _Traits> _Istream; |
| __is.flags(_Istream::dec | _Istream::skipws); |
| result_type __m; |
| result_type __n; |
| __is >> __m >> __n; |
| if (!__is.fail()) |
| __x.param(param_type(__m, __n)); |
| return __is; |
| } |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| _LIBCPP_POP_MACROS |
| |
| #endif // _LIBCPP___RANDOM_FISHER_F_DISTRIBUTION_H |