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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___RANDOM_WEIBULL_DISTRIBUTION_H10#define _LIBCPP___RANDOM_WEIBULL_DISTRIBUTION_H11 12#include <__config>13#include <__random/exponential_distribution.h>14#include <__random/is_valid.h>15#include <cmath>16#include <iosfwd>17#include <limits>18 19#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)20# pragma GCC system_header21#endif22 23_LIBCPP_PUSH_MACROS24#include <__undef_macros>25 26_LIBCPP_BEGIN_NAMESPACE_STD27 28template <class _RealType = double>29class 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 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#ifndef _LIBCPP_CXX03_LANG61 _LIBCPP_HIDE_FROM_ABI weibull_distribution() : weibull_distribution(1) {}62 _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(result_type __a, result_type __b = 1)63 : __p_(param_type(__a, __b)) {}64#else65 _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(result_type __a = 1, result_type __b = 1)66 : __p_(param_type(__a, __b)) {}67#endif68 _LIBCPP_HIDE_FROM_ABI explicit weibull_distribution(const param_type& __p) : __p_(__p) {}69 _LIBCPP_HIDE_FROM_ABI void reset() {}70 71 // generating functions72 template <class _URNG>73 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {74 return (*this)(__g, __p_);75 }76 template <class _URNG>77 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {78 return __p.b() * std::pow(exponential_distribution<result_type>()(__g), 1 / __p.a());79 }80 81 // property functions82 _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }83 _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }84 85 _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }86 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }87 88 _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }89 _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }90 91 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const weibull_distribution& __x, const weibull_distribution& __y) {92 return __x.__p_ == __y.__p_;93 }94 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const weibull_distribution& __x, const weibull_distribution& __y) {95 return !(__x == __y);96 }97};98 99template <class _CharT, class _Traits, class _RT>100_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&101operator<<(basic_ostream<_CharT, _Traits>& __os, const weibull_distribution<_RT>& __x) {102 __save_flags<_CharT, _Traits> __lx(__os);103 typedef basic_ostream<_CharT, _Traits> _OStream;104 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);105 _CharT __sp = __os.widen(' ');106 __os.fill(__sp);107 __os << __x.a() << __sp << __x.b();108 return __os;109}110 111template <class _CharT, class _Traits, class _RT>112_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&113operator>>(basic_istream<_CharT, _Traits>& __is, weibull_distribution<_RT>& __x) {114 typedef weibull_distribution<_RT> _Eng;115 typedef typename _Eng::result_type result_type;116 typedef typename _Eng::param_type param_type;117 __save_flags<_CharT, _Traits> __lx(__is);118 typedef basic_istream<_CharT, _Traits> _Istream;119 __is.flags(_Istream::dec | _Istream::skipws);120 result_type __a;121 result_type __b;122 __is >> __a >> __b;123 if (!__is.fail())124 __x.param(param_type(__a, __b));125 return __is;126}127 128_LIBCPP_END_NAMESPACE_STD129 130_LIBCPP_POP_MACROS131 132#endif // _LIBCPP___RANDOM_WEIBULL_DISTRIBUTION_H133