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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_LOGNORMAL_DISTRIBUTION_H10#define _LIBCPP___RANDOM_LOGNORMAL_DISTRIBUTION_H11 12#include <__config>13#include <__random/is_valid.h>14#include <__random/normal_distribution.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 lognormal_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 __m_;39 result_type __s_;40 41 public:42 typedef lognormal_distribution distribution_type;43 44 _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __m = 0, result_type __s = 1) : __m_(__m), __s_(__s) {}45 46 _LIBCPP_HIDE_FROM_ABI result_type m() const { return __m_; }47 _LIBCPP_HIDE_FROM_ABI result_type s() const { return __s_; }48 49 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {50 return __x.__m_ == __y.__m_ && __x.__s_ == __y.__s_;51 }52 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }53 };54 55private:56 normal_distribution<result_type> __nd_;57 58public:59 // constructor and reset functions60#ifndef _LIBCPP_CXX03_LANG61 _LIBCPP_HIDE_FROM_ABI lognormal_distribution() : lognormal_distribution(0) {}62 _LIBCPP_HIDE_FROM_ABI explicit lognormal_distribution(result_type __m, result_type __s = 1) : __nd_(__m, __s) {}63#else64 _LIBCPP_HIDE_FROM_ABI explicit lognormal_distribution(result_type __m = 0, result_type __s = 1) : __nd_(__m, __s) {}65#endif66 _LIBCPP_HIDE_FROM_ABI explicit lognormal_distribution(const param_type& __p) : __nd_(__p.m(), __p.s()) {}67 _LIBCPP_HIDE_FROM_ABI void reset() { __nd_.reset(); }68 69 // generating functions70 template <class _URNG>71 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {72 return std::exp(__nd_(__g));73 }74 75 template <class _URNG>76 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {77 typename normal_distribution<result_type>::param_type __pn(__p.m(), __p.s());78 return std::exp(__nd_(__g, __pn));79 }80 81 // property functions82 _LIBCPP_HIDE_FROM_ABI result_type m() const { return __nd_.mean(); }83 _LIBCPP_HIDE_FROM_ABI result_type s() const { return __nd_.stddev(); }84 85 _LIBCPP_HIDE_FROM_ABI param_type param() const { return param_type(__nd_.mean(), __nd_.stddev()); }86 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) {87 typename normal_distribution<result_type>::param_type __pn(__p.m(), __p.s());88 __nd_.param(__pn);89 }90 91 _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }92 _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::infinity(); }93 94 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const lognormal_distribution& __x, const lognormal_distribution& __y) {95 return __x.__nd_ == __y.__nd_;96 }97 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const lognormal_distribution& __x, const lognormal_distribution& __y) {98 return !(__x == __y);99 }100 101 template <class _CharT, class _Traits, class _RT>102 friend basic_ostream<_CharT, _Traits>&103 operator<<(basic_ostream<_CharT, _Traits>& __os, const lognormal_distribution<_RT>& __x);104 105 template <class _CharT, class _Traits, class _RT>106 friend basic_istream<_CharT, _Traits>&107 operator>>(basic_istream<_CharT, _Traits>& __is, lognormal_distribution<_RT>& __x);108};109 110template <class _CharT, class _Traits, class _RT>111inline _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&112operator<<(basic_ostream<_CharT, _Traits>& __os, const lognormal_distribution<_RT>& __x) {113 return __os << __x.__nd_;114}115 116template <class _CharT, class _Traits, class _RT>117inline _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&118operator>>(basic_istream<_CharT, _Traits>& __is, lognormal_distribution<_RT>& __x) {119 return __is >> __x.__nd_;120}121 122_LIBCPP_END_NAMESPACE_STD123 124_LIBCPP_POP_MACROS125 126#endif // _LIBCPP___RANDOM_LOGNORMAL_DISTRIBUTION_H127