368faacac7
This commit reverts 5aaefa51 (and also partly 7f285f48e77 and b6d75682f9, which were related to the original commit). As landed, 5aaefa51 had unintended consequences on some downstream bots and didn't have proper coverage upstream due to a few subtle things. Implementing this is something we should do in libc++, however we'll first need to address a few issues listed in https://reviews.llvm.org/D106124#3349710. Differential Revision: https://reviews.llvm.org/D120683
145 lines
4.4 KiB
C++
145 lines
4.4 KiB
C++
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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_CHI_SQUARED_DISTRIBUTION_H
|
|
#define _LIBCPP___RANDOM_CHI_SQUARED_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 chi_squared_distribution
|
|
{
|
|
public:
|
|
// types
|
|
typedef _RealType result_type;
|
|
|
|
class _LIBCPP_TEMPLATE_VIS param_type
|
|
{
|
|
result_type __n_;
|
|
public:
|
|
typedef chi_squared_distribution distribution_type;
|
|
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
explicit param_type(result_type __n = 1) : __n_(__n) {}
|
|
|
|
_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.__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
|
|
chi_squared_distribution() : chi_squared_distribution(1) {}
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
explicit chi_squared_distribution(result_type __n)
|
|
: __p_(param_type(__n)) {}
|
|
#else
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
explicit chi_squared_distribution(result_type __n = 1)
|
|
: __p_(param_type(__n)) {}
|
|
#endif
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
explicit chi_squared_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>
|
|
_LIBCPP_INLINE_VISIBILITY
|
|
result_type operator()(_URNG& __g, const param_type& __p)
|
|
{return gamma_distribution<result_type>(__p.n() / 2, 2)(__g);}
|
|
|
|
// property functions
|
|
_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 chi_squared_distribution& __x,
|
|
const chi_squared_distribution& __y)
|
|
{return __x.__p_ == __y.__p_;}
|
|
friend _LIBCPP_INLINE_VISIBILITY
|
|
bool operator!=(const chi_squared_distribution& __x,
|
|
const chi_squared_distribution& __y)
|
|
{return !(__x == __y);}
|
|
};
|
|
|
|
template <class _CharT, class _Traits, class _RT>
|
|
basic_ostream<_CharT, _Traits>&
|
|
operator<<(basic_ostream<_CharT, _Traits>& __os,
|
|
const chi_squared_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);
|
|
__os << __x.n();
|
|
return __os;
|
|
}
|
|
|
|
template <class _CharT, class _Traits, class _RT>
|
|
basic_istream<_CharT, _Traits>&
|
|
operator>>(basic_istream<_CharT, _Traits>& __is,
|
|
chi_squared_distribution<_RT>& __x)
|
|
{
|
|
typedef chi_squared_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 __n;
|
|
__is >> __n;
|
|
if (!__is.fail())
|
|
__x.param(param_type(__n));
|
|
return __is;
|
|
}
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
_LIBCPP_POP_MACROS
|
|
|
|
#endif // _LIBCPP___RANDOM_CHI_SQUARED_DISTRIBUTION_H
|