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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CXX03___RANDOM_WEIBULL_DISTRIBUTION_H10#define _LIBCPP___CXX03___RANDOM_WEIBULL_DISTRIBUTION_H11 12#include <__cxx03/__config>13#include <__cxx03/__random/exponential_distribution.h>14#include <__cxx03/__random/is_valid.h>15#include <__cxx03/cmath>16#include <__cxx03/iosfwd>17#include <__cxx03/limits>18 19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)20# pragma GCC system_header21#endif22 23_LIBCPP_PUSH_MACROS24#include <__cxx03/__undef_macros>25 26_LIBCPP_BEGIN_NAMESPACE_STD27 28template <class _RealType = double>29class _LIBCPP_TEMPLATE_VIS weibull_distribution {30 static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,31 "RealType must be a supported floating-point type");32 33public:34 // types35 typedef _RealType result_type;36 37 class _LIBCPP_TEMPLATE_VIS param_type {38 result_type __a_;39 result_type __b_;40 41 public:42 typedef weibull_distribution distribution_type;43 44 _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 1, result_type __b = 1) : __a_(__a), __b_(__b) {}45 46 _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }47 _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }48 49 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {50 return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;51 }52 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }53 };54 55private:56 param_type __p_;57 58public:59 // constructor and reset functions60 _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(result_type __a = 1, result_type __b = 1)61 : __p_(param_type(__a, __b)) {}62 _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(const param_type& __p) : __p_(__p) {}63 _LIBCPP_HIDE_FROM_ABI void reset() {}64 65 // generating functions66 template <class _URNG>67 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {68 return (*this)(__g, __p_);69 }70 template <class _URNG>71 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {72 return __p.b() * std::pow(exponential_distribution<result_type>()(__g), 1 / __p.a());73 }74 75 // property functions76 _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }77 _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }78 79 _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }80 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }81 82 _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }83 _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }84 85 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const weibull_distribution& __x, const weibull_distribution& __y) {86 return __x.__p_ == __y.__p_;87 }88 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const weibull_distribution& __x, const weibull_distribution& __y) {89 return !(__x == __y);90 }91};92 93template <class _CharT, class _Traits, class _RT>94_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&95operator<<(basic_ostream<_CharT, _Traits>& __os, const weibull_distribution<_RT>& __x) {96 __save_flags<_CharT, _Traits> __lx(__os);97 typedef basic_ostream<_CharT, _Traits> _OStream;98 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);99 _CharT __sp = __os.widen(' ');100 __os.fill(__sp);101 __os << __x.a() << __sp << __x.b();102 return __os;103}104 105template <class _CharT, class _Traits, class _RT>106_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&107operator>>(basic_istream<_CharT, _Traits>& __is, weibull_distribution<_RT>& __x) {108 typedef weibull_distribution<_RT> _Eng;109 typedef typename _Eng::result_type result_type;110 typedef typename _Eng::param_type param_type;111 __save_flags<_CharT, _Traits> __lx(__is);112 typedef basic_istream<_CharT, _Traits> _Istream;113 __is.flags(_Istream::dec | _Istream::skipws);114 result_type __a;115 result_type __b;116 __is >> __a >> __b;117 if (!__is.fail())118 __x.param(param_type(__a, __b));119 return __is;120}121 122_LIBCPP_END_NAMESPACE_STD123 124_LIBCPP_POP_MACROS125 126#endif // _LIBCPP___CXX03___RANDOM_WEIBULL_DISTRIBUTION_H127