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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H 10 #define _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H 11 12 #include <__config> 13 #include <__random/generate_canonical.h> 14 #include <__random/is_valid.h> 15 #include <iosfwd> 16 #include <limits> 17 #include <type_traits> 18 19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 20 # pragma GCC system_header 21 #endif 22 23 _LIBCPP_PUSH_MACROS 24 #include <__undef_macros> 25 26 _LIBCPP_BEGIN_NAMESPACE_STD 27 28 template<class _RealType = double> 29 class _LIBCPP_TEMPLATE_VIS uniform_real_distribution 30 { 31 public: 32 // types 33 typedef _RealType result_type; 34 35 class _LIBCPP_TEMPLATE_VIS param_type 36 { 37 result_type __a_; 38 result_type __b_; 39 public: 40 typedef uniform_real_distribution distribution_type; 41 42 _LIBCPP_INLINE_VISIBILITY 43 explicit param_type(result_type __a = 0, 44 result_type __b = 1) 45 : __a_(__a), __b_(__b) {} 46 47 _LIBCPP_INLINE_VISIBILITY 48 result_type a() const {return __a_;} 49 _LIBCPP_INLINE_VISIBILITY 50 result_type b() const {return __b_;} 51 52 friend _LIBCPP_INLINE_VISIBILITY 53 bool operator==(const param_type& __x, const param_type& __y) 54 {return __x.__a_ == __y.__a_ && __x.__b_ == __y.__b_;} 55 friend _LIBCPP_INLINE_VISIBILITY 56 bool operator!=(const param_type& __x, const param_type& __y) 57 {return !(__x == __y);} 58 }; 59 60 private: 61 param_type __p_; 62 63 public: 64 // constructors and reset functions 65 #ifndef _LIBCPP_CXX03_LANG 66 _LIBCPP_INLINE_VISIBILITY 67 uniform_real_distribution() : uniform_real_distribution(0) {} 68 explicit uniform_real_distribution(result_type __a, result_type __b = 1) 69 : __p_(param_type(__a, __b)) {} 70 #else 71 _LIBCPP_INLINE_VISIBILITY 72 explicit uniform_real_distribution(result_type __a = 0, result_type __b = 1) 73 : __p_(param_type(__a, __b)) {} 74 #endif 75 _LIBCPP_INLINE_VISIBILITY 76 explicit uniform_real_distribution(const param_type& __p) : __p_(__p) {} 77 _LIBCPP_INLINE_VISIBILITY 78 void reset() {} 79 80 // generating functions 81 template<class _URNG> 82 _LIBCPP_INLINE_VISIBILITY 83 result_type operator()(_URNG& __g) 84 {return (*this)(__g, __p_);} 85 template<class _URNG> _LIBCPP_INLINE_VISIBILITY result_type operator()(_URNG& __g, const param_type& __p); 86 87 // property functions 88 _LIBCPP_INLINE_VISIBILITY 89 result_type a() const {return __p_.a();} 90 _LIBCPP_INLINE_VISIBILITY 91 result_type b() const {return __p_.b();} 92 93 _LIBCPP_INLINE_VISIBILITY 94 param_type param() const {return __p_;} 95 _LIBCPP_INLINE_VISIBILITY 96 void param(const param_type& __p) {__p_ = __p;} 97 98 _LIBCPP_INLINE_VISIBILITY 99 result_type min() const {return a();} 100 _LIBCPP_INLINE_VISIBILITY 101 result_type max() const {return b();} 102 103 friend _LIBCPP_INLINE_VISIBILITY 104 bool operator==(const uniform_real_distribution& __x, 105 const uniform_real_distribution& __y) 106 {return __x.__p_ == __y.__p_;} 107 friend _LIBCPP_INLINE_VISIBILITY 108 bool operator!=(const uniform_real_distribution& __x, 109 const uniform_real_distribution& __y) 110 {return !(__x == __y);} 111 }; 112 113 template<class _RealType> 114 template<class _URNG> 115 inline 116 typename uniform_real_distribution<_RealType>::result_type 117 uniform_real_distribution<_RealType>::operator()(_URNG& __g, const param_type& __p) 118 { 119 static_assert(__libcpp_random_is_valid_urng<_URNG>::value, ""); 120 return (__p.b() - __p.a()) 121 * _VSTD::generate_canonical<_RealType, numeric_limits<_RealType>::digits>(__g) 122 + __p.a(); 123 } 124 125 template <class _CharT, class _Traits, class _RT> 126 _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>& 127 operator<<(basic_ostream<_CharT, _Traits>& __os, 128 const uniform_real_distribution<_RT>& __x) 129 { 130 __save_flags<_CharT, _Traits> __lx(__os); 131 typedef basic_ostream<_CharT, _Traits> _OStream; 132 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | 133 _OStream::scientific); 134 _CharT __sp = __os.widen(' '); 135 __os.fill(__sp); 136 return __os << __x.a() << __sp << __x.b(); 137 } 138 139 template <class _CharT, class _Traits, class _RT> 140 _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>& 141 operator>>(basic_istream<_CharT, _Traits>& __is, 142 uniform_real_distribution<_RT>& __x) 143 { 144 typedef uniform_real_distribution<_RT> _Eng; 145 typedef typename _Eng::result_type result_type; 146 typedef typename _Eng::param_type param_type; 147 __save_flags<_CharT, _Traits> __lx(__is); 148 typedef basic_istream<_CharT, _Traits> _Istream; 149 __is.flags(_Istream::dec | _Istream::skipws); 150 result_type __a; 151 result_type __b; 152 __is >> __a >> __b; 153 if (!__is.fail()) 154 __x.param(param_type(__a, __b)); 155 return __is; 156 } 157 158 _LIBCPP_END_NAMESPACE_STD 159 160 _LIBCPP_POP_MACROS 161 162 #endif // _LIBCPP___RANDOM_UNIFORM_REAL_DISTRIBUTION_H 163