368faacac7
This commit reverts5aaefa51(and also partly7f285f48e7andb6d75682f9, which were related to the original commit). As landed,5aaefa51had 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
|