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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_UNIFORM_REAL_DISTRIBUTION_H10#define _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H11 12#include <__config>13#include <__random/generate_canonical.h>14#include <__random/is_valid.h>15#include <iosfwd>16#include <limits>17 18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)19# pragma GCC system_header20#endif21 22_LIBCPP_PUSH_MACROS23#include <__undef_macros>24 25_LIBCPP_BEGIN_NAMESPACE_STD26 27template <class _RealType = double>28class uniform_real_distribution {29 static_assert(__libcpp_random_is_valid_realtype<_RealType>::value,30 "RealType must be a supported floating-point type");31 32public:33 // types34 typedef _RealType result_type;35 36 class param_type {37 result_type __a_;38 result_type __b_;39 40 public:41 typedef uniform_real_distribution distribution_type;42 43 _LIBCPP_HIDE_FROM_ABI explicit param_type(result_type __a = 0, result_type __b = 1) : __a_(__a), __b_(__b) {}44 45 _LIBCPP_HIDE_FROM_ABI result_type a() const { return __a_; }46 _LIBCPP_HIDE_FROM_ABI result_type b() const { return __b_; }47 48 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {49 return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;50 }51 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }52 };53 54private:55 param_type __p_;56 57public:58 // constructors and reset functions59#ifndef _LIBCPP_CXX03_LANG60 _LIBCPP_HIDE_FROM_ABI uniform_real_distribution() : uniform_real_distribution(0) {}61 _LIBCPP_HIDE_FROM_ABI explicit uniform_real_distribution(result_type __a, result_type __b = 1)62 : __p_(param_type(__a, __b)) {}63#else64 _LIBCPP_HIDE_FROM_ABI explicit uniform_real_distribution(result_type __a = 0, result_type __b = 1)65 : __p_(param_type(__a, __b)) {}66#endif67 _LIBCPP_HIDE_FROM_ABI explicit uniform_real_distribution(const param_type& __p) : __p_(__p) {}68 _LIBCPP_HIDE_FROM_ABI void reset() {}69 70 // generating functions71 template <class _URNG>72 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {73 return (*this)(__g, __p_);74 }75 template <class _URNG>76 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);77 78 // property functions79 _LIBCPP_HIDE_FROM_ABI result_type a() const { return __p_.a(); }80 _LIBCPP_HIDE_FROM_ABI result_type b() const { return __p_.b(); }81 82 _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }83 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }84 85 _LIBCPP_HIDE_FROM_ABI result_type min() const { return a(); }86 _LIBCPP_HIDE_FROM_ABI result_type max() const { return b(); }87 88 friend _LIBCPP_HIDE_FROM_ABI bool89 operator==(const uniform_real_distribution& __x, const uniform_real_distribution& __y) {90 return __x.__p_ == __y.__p_;91 }92 friend _LIBCPP_HIDE_FROM_ABI bool93 operator!=(const uniform_real_distribution& __x, const uniform_real_distribution& __y) {94 return !(__x == __y);95 }96};97 98template <class _RealType>99template <class _URNG>100inline typename uniform_real_distribution<_RealType>::result_type101uniform_real_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) {102 static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");103 return (__p.b() - __p.a()) * std::generate_canonical<_RealType, numeric_limits<_RealType>::digits>(__g) + __p.a();104}105 106template <class _CharT, class _Traits, class _RT>107_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&108operator<<(basic_ostream<_CharT, _Traits>& __os, const uniform_real_distribution<_RT>& __x) {109 __save_flags<_CharT, _Traits> __lx(__os);110 typedef basic_ostream<_CharT, _Traits> _OStream;111 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);112 _CharT __sp = __os.widen(' ');113 __os.fill(__sp);114 return __os << __x.a() << __sp << __x.b();115}116 117template <class _CharT, class _Traits, class _RT>118_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&119operator>>(basic_istream<_CharT, _Traits>& __is, uniform_real_distribution<_RT>& __x) {120 typedef uniform_real_distribution<_RT> _Eng;121 typedef typename _Eng::result_type result_type;122 typedef typename _Eng::param_type param_type;123 __save_flags<_CharT, _Traits> __lx(__is);124 typedef basic_istream<_CharT, _Traits> _Istream;125 __is.flags(_Istream::dec | _Istream::skipws);126 result_type __a;127 result_type __b;128 __is >> __a >> __b;129 if (!__is.fail())130 __x.param(param_type(__a, __b));131 return __is;132}133 134_LIBCPP_END_NAMESPACE_STD135 136_LIBCPP_POP_MACROS137 138#endif // _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H139