xref: /freebsd-src/contrib/llvm-project/libcxx/include/__random/bernoulli_distribution.h (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
14824e7fdSDimitry Andric //===----------------------------------------------------------------------===//
24824e7fdSDimitry Andric //
34824e7fdSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
44824e7fdSDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
54824e7fdSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
64824e7fdSDimitry Andric //
74824e7fdSDimitry Andric //===----------------------------------------------------------------------===//
84824e7fdSDimitry Andric 
94824e7fdSDimitry Andric #ifndef _LIBCPP___RANDOM_BERNOULLI_DISTRIBUTION_H
104824e7fdSDimitry Andric #define _LIBCPP___RANDOM_BERNOULLI_DISTRIBUTION_H
114824e7fdSDimitry Andric 
124824e7fdSDimitry Andric #include <__config>
1381ad6265SDimitry Andric #include <__random/is_valid.h>
144824e7fdSDimitry Andric #include <__random/uniform_real_distribution.h>
154824e7fdSDimitry Andric #include <iosfwd>
164824e7fdSDimitry Andric 
174824e7fdSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
184824e7fdSDimitry Andric #  pragma GCC system_header
194824e7fdSDimitry Andric #endif
204824e7fdSDimitry Andric 
214824e7fdSDimitry Andric _LIBCPP_PUSH_MACROS
224824e7fdSDimitry Andric #include <__undef_macros>
234824e7fdSDimitry Andric 
244824e7fdSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
254824e7fdSDimitry Andric 
264824e7fdSDimitry Andric class _LIBCPP_TEMPLATE_VIS bernoulli_distribution
274824e7fdSDimitry Andric {
284824e7fdSDimitry Andric public:
294824e7fdSDimitry Andric     // types
304824e7fdSDimitry Andric     typedef bool result_type;
314824e7fdSDimitry Andric 
324824e7fdSDimitry Andric     class _LIBCPP_TEMPLATE_VIS param_type
334824e7fdSDimitry Andric     {
344824e7fdSDimitry Andric         double __p_;
354824e7fdSDimitry Andric     public:
364824e7fdSDimitry Andric         typedef bernoulli_distribution distribution_type;
374824e7fdSDimitry Andric 
384824e7fdSDimitry Andric         _LIBCPP_INLINE_VISIBILITY
394824e7fdSDimitry Andric         explicit param_type(double __p = 0.5) : __p_(__p) {}
404824e7fdSDimitry Andric 
414824e7fdSDimitry Andric         _LIBCPP_INLINE_VISIBILITY
424824e7fdSDimitry Andric         double p() const {return __p_;}
434824e7fdSDimitry Andric 
444824e7fdSDimitry Andric         friend _LIBCPP_INLINE_VISIBILITY
454824e7fdSDimitry Andric             bool operator==(const param_type& __x, const param_type& __y)
464824e7fdSDimitry Andric             {return __x.__p_ == __y.__p_;}
474824e7fdSDimitry Andric         friend _LIBCPP_INLINE_VISIBILITY
484824e7fdSDimitry Andric             bool operator!=(const param_type& __x, const param_type& __y)
494824e7fdSDimitry Andric             {return !(__x == __y);}
504824e7fdSDimitry Andric     };
514824e7fdSDimitry Andric 
524824e7fdSDimitry Andric private:
534824e7fdSDimitry Andric     param_type __p_;
544824e7fdSDimitry Andric 
554824e7fdSDimitry Andric public:
564824e7fdSDimitry Andric     // constructors and reset functions
574824e7fdSDimitry Andric #ifndef _LIBCPP_CXX03_LANG
584824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
594824e7fdSDimitry Andric     bernoulli_distribution() : bernoulli_distribution(0.5) {}
604824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
614824e7fdSDimitry Andric     explicit bernoulli_distribution(double __p) : __p_(param_type(__p)) {}
624824e7fdSDimitry Andric #else
634824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
644824e7fdSDimitry Andric     explicit bernoulli_distribution(double __p = 0.5) : __p_(param_type(__p)) {}
654824e7fdSDimitry Andric #endif
664824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
674824e7fdSDimitry Andric     explicit bernoulli_distribution(const param_type& __p) : __p_(__p) {}
684824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
694824e7fdSDimitry Andric     void reset() {}
704824e7fdSDimitry Andric 
714824e7fdSDimitry Andric     // generating functions
724824e7fdSDimitry Andric     template<class _URNG>
734824e7fdSDimitry Andric         _LIBCPP_INLINE_VISIBILITY
744824e7fdSDimitry Andric         result_type operator()(_URNG& __g)
754824e7fdSDimitry Andric         {return (*this)(__g, __p_);}
764824e7fdSDimitry Andric     template<class _URNG> _LIBCPP_INLINE_VISIBILITY result_type operator()(_URNG& __g, const param_type& __p);
774824e7fdSDimitry Andric 
784824e7fdSDimitry Andric     // property functions
794824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
804824e7fdSDimitry Andric     double p() const {return __p_.p();}
814824e7fdSDimitry Andric 
824824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
834824e7fdSDimitry Andric     param_type param() const {return __p_;}
844824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
854824e7fdSDimitry Andric     void param(const param_type& __p) {__p_ = __p;}
864824e7fdSDimitry Andric 
874824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
884824e7fdSDimitry Andric     result_type min() const {return false;}
894824e7fdSDimitry Andric     _LIBCPP_INLINE_VISIBILITY
904824e7fdSDimitry Andric     result_type max() const {return true;}
914824e7fdSDimitry Andric 
924824e7fdSDimitry Andric     friend _LIBCPP_INLINE_VISIBILITY
934824e7fdSDimitry Andric         bool operator==(const bernoulli_distribution& __x,
944824e7fdSDimitry Andric                         const bernoulli_distribution& __y)
954824e7fdSDimitry Andric         {return __x.__p_ == __y.__p_;}
964824e7fdSDimitry Andric     friend _LIBCPP_INLINE_VISIBILITY
974824e7fdSDimitry Andric         bool operator!=(const bernoulli_distribution& __x,
984824e7fdSDimitry Andric                         const bernoulli_distribution& __y)
994824e7fdSDimitry Andric         {return !(__x == __y);}
1004824e7fdSDimitry Andric };
1014824e7fdSDimitry Andric 
1024824e7fdSDimitry Andric template<class _URNG>
1034824e7fdSDimitry Andric inline
1044824e7fdSDimitry Andric bernoulli_distribution::result_type
1054824e7fdSDimitry Andric bernoulli_distribution::operator()(_URNG& __g, const param_type& __p)
1064824e7fdSDimitry Andric {
10781ad6265SDimitry Andric     static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");
1084824e7fdSDimitry Andric     uniform_real_distribution<double> __gen;
1094824e7fdSDimitry Andric     return __gen(__g) < __p.p();
1104824e7fdSDimitry Andric }
1114824e7fdSDimitry Andric 
1124824e7fdSDimitry Andric template <class _CharT, class _Traits>
113*bdd1243dSDimitry Andric _LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&
1144824e7fdSDimitry Andric operator<<(basic_ostream<_CharT, _Traits>& __os, const bernoulli_distribution& __x)
1154824e7fdSDimitry Andric {
1164824e7fdSDimitry Andric     __save_flags<_CharT, _Traits> __lx(__os);
1174824e7fdSDimitry Andric     typedef basic_ostream<_CharT, _Traits> _OStream;
1184824e7fdSDimitry Andric     __os.flags(_OStream::dec | _OStream::left | _OStream::fixed |
1194824e7fdSDimitry Andric                _OStream::scientific);
1204824e7fdSDimitry Andric     _CharT __sp = __os.widen(' ');
1214824e7fdSDimitry Andric     __os.fill(__sp);
1224824e7fdSDimitry Andric     return __os << __x.p();
1234824e7fdSDimitry Andric }
1244824e7fdSDimitry Andric 
1254824e7fdSDimitry Andric template <class _CharT, class _Traits>
126*bdd1243dSDimitry Andric _LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&
1274824e7fdSDimitry Andric operator>>(basic_istream<_CharT, _Traits>& __is, bernoulli_distribution& __x)
1284824e7fdSDimitry Andric {
1294824e7fdSDimitry Andric     typedef bernoulli_distribution _Eng;
1304824e7fdSDimitry Andric     typedef typename _Eng::param_type param_type;
1314824e7fdSDimitry Andric     __save_flags<_CharT, _Traits> __lx(__is);
1324824e7fdSDimitry Andric     typedef basic_istream<_CharT, _Traits> _Istream;
1334824e7fdSDimitry Andric     __is.flags(_Istream::dec | _Istream::skipws);
1344824e7fdSDimitry Andric     double __p;
1354824e7fdSDimitry Andric     __is >> __p;
1364824e7fdSDimitry Andric     if (!__is.fail())
1374824e7fdSDimitry Andric         __x.param(param_type(__p));
1384824e7fdSDimitry Andric     return __is;
1394824e7fdSDimitry Andric }
1404824e7fdSDimitry Andric 
1414824e7fdSDimitry Andric _LIBCPP_END_NAMESPACE_STD
1424824e7fdSDimitry Andric 
1434824e7fdSDimitry Andric _LIBCPP_POP_MACROS
1444824e7fdSDimitry Andric 
1454824e7fdSDimitry Andric #endif // _LIBCPP___RANDOM_BERNOULLI_DISTRIBUTION_H
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