29 #ifndef _GLIBCXX_EXPERIMENTAL_ALGORITHM 30 #define _GLIBCXX_EXPERIMENTAL_ALGORITHM 1 32 #pragma GCC system_header 34 #if __cplusplus <= 201103L 42 namespace std _GLIBCXX_VISIBILITY(default)
44 namespace experimental
46 inline namespace fundamentals_v1
48 _GLIBCXX_BEGIN_NAMESPACE_VERSION
50 template<
typename _ForwardIterator,
typename _Searcher>
51 inline _ForwardIterator
52 search(_ForwardIterator __first, _ForwardIterator __last,
53 const _Searcher& __searcher)
54 {
return __searcher(__first, __last); }
56 #define __cpp_lib_experimental_sample 201402 59 template<
typename _InputIterator,
typename _RandomAccessIterator,
60 typename _Size,
typename _UniformRandomNumberGenerator>
64 _Size __n, _UniformRandomNumberGenerator&& __g)
67 using __param_type =
typename __distrib_type::param_type;
69 _Size __sample_sz = 0;
70 while (__first != __last && __sample_sz != __n)
72 __out[__sample_sz++] = *__first;
75 for (
auto __pop_sz = __sample_sz; __first != __last;
76 ++__first, (void)++__pop_sz)
78 const auto __k = __d(__g, __param_type{0, __pop_sz});
80 __out[__k] = *__first;
82 return __out + __sample_sz;
86 template<
typename _ForwardIterator,
typename _OutputIterator,
typename _Cat,
87 typename _Size,
typename _UniformRandomNumberGenerator>
89 __sample(_ForwardIterator __first, _ForwardIterator __last,
91 _OutputIterator __out, _Cat,
92 _Size __n, _UniformRandomNumberGenerator&& __g)
95 using __param_type =
typename __distrib_type::param_type;
98 for (__n =
std::min(__n, __unsampled_sz); __n != 0; ++__first)
99 if (__d(__g, __param_type{0, --__unsampled_sz}) < __n)
108 template<
typename _PopulationIterator,
typename _SampleIterator,
109 typename _Distance,
typename _UniformRandomNumberGenerator>
111 sample(_PopulationIterator __first, _PopulationIterator __last,
112 _SampleIterator __out, _Distance __n,
113 _UniformRandomNumberGenerator&& __g)
115 using __pop_cat =
typename 116 std::iterator_traits<_PopulationIterator>::iterator_category;
117 using __samp_cat =
typename 118 std::iterator_traits<_SampleIterator>::iterator_category;
121 __or_<is_convertible<__pop_cat, forward_iterator_tag>,
122 is_convertible<__samp_cat, random_access_iterator_tag>>::value,
123 "output range must use a RandomAccessIterator when input range" 124 " does not meet the ForwardIterator requirements");
127 "sample size must be an integer type");
129 typename iterator_traits<_PopulationIterator>::difference_type __d = __n;
130 return std::experimental::__sample(
131 __first, __last, __pop_cat{}, __out, __samp_cat{},
132 __d, std::forward<_UniformRandomNumberGenerator>(__g));
135 _GLIBCXX_END_NAMESPACE_VERSION
142 #endif // _GLIBCXX_EXPERIMENTAL_ALGORITHM Random-access iterators support a superset of bidirectional iterator operations.
iterator_traits< _InputIterator >::difference_type distance(_InputIterator __first, _InputIterator __last)
A generalization of pointer arithmetic.
_RandomAccessIterator __sample(_InputIterator __first, _InputIterator __last, input_iterator_tag, _RandomAccessIterator __out, random_access_iterator_tag, _Size __n, _UniformRandomNumberGenerator &&__g)
Reservoir sampling algorithm.
_GLIBCXX14_CONSTEXPR const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Uniform discrete distribution for random numbers.
ISO C++ entities toplevel namespace is std.
_SampleIterator sample(_PopulationIterator __first, _PopulationIterator __last, _SampleIterator __out, _Distance __n, _UniformRandomNumberGenerator &&__g)
Take a random sample from a population.
Forward iterators support a superset of input iterator operations.