| /* | |
| * Copyright 2008-2013 NVIDIA Corporation | |
| * | |
| * Licensed under the Apache License, Version 2.0 (the "License"); | |
| * you may not use this file except in compliance with the License. | |
| * You may obtain a copy of the License at | |
| * | |
| * http://www.apache.org/licenses/LICENSE-2.0 | |
| * | |
| * Unless required by applicable law or agreed to in writing, software | |
| * distributed under the License is distributed on an "AS IS" BASIS, | |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| * See the License for the specific language governing permissions and | |
| * limitations under the License. | |
| */ | |
| /*! \file count.h | |
| * \brief Counting elements in a range | |
| */ | |
| THRUST_NAMESPACE_BEGIN | |
| /*! \addtogroup algorithms | |
| */ | |
| /*! \addtogroup reductions | |
| * \ingroup algorithms | |
| * \{ | |
| */ | |
| /*! \addtogroup counting | |
| * \ingroup reductions | |
| * \{ | |
| */ | |
| /*! \p count finds the number of elements in <tt>[first,last)</tt> that are equal | |
| * to \p value. More precisely, \p count returns the number of iterators \c i in | |
| * <tt>[first, last)</tt> such that <tt>*i == value</tt>. | |
| * | |
| * The algorithm's execution is parallelized as determined by \p exec. | |
| * | |
| * \param exec The execution policy to use for parallelization. | |
| * \param first The beginning of the sequence. | |
| * \param last The end of the sequence. | |
| * \param value The value to be counted. | |
| * \return The number of elements equal to \p value. | |
| * | |
| * \tparam DerivedPolicy The name of the derived execution policy. | |
| * \tparam InputIterator must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator's \c value_type must be a model of must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/equality_comparable">Equality Comparable</a>. | |
| * \tparam EqualityComparable must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/equality_comparable">Equality Comparable</a> and can be compared for equality with \c InputIterator's \c value_type | |
| * | |
| * The following code snippet demonstrates how to use \p count to | |
| * count the number of instances in a range of a value of interest using the \p thrust::device execution policy: | |
| * | |
| * \code | |
| * #include <thrust/count.h> | |
| * #include <thrust/device_vector.h> | |
| * #include <thrust/execution_policy.h> | |
| * ... | |
| * // put 3 1s in a device_vector | |
| * thrust::device_vector<int> vec(5,0); | |
| * vec[1] = 1; | |
| * vec[3] = 1; | |
| * vec[4] = 1; | |
| * | |
| * // count the 1s | |
| * int result = thrust::count(thrust::device, vec.begin(), vec.end(), 1); | |
| * // result == 3 | |
| * \endcode | |
| * | |
| * \see https://en.cppreference.com/w/cpp/algorithm/count | |
| */ | |
| template<typename DerivedPolicy, typename InputIterator, typename EqualityComparable> | |
| __host__ __device__ | |
| typename thrust::iterator_traits<InputIterator>::difference_type | |
| count(const thrust::detail::execution_policy_base<DerivedPolicy> &exec, InputIterator first, InputIterator last, const EqualityComparable& value); | |
| /*! \p count finds the number of elements in <tt>[first,last)</tt> that are equal | |
| * to \p value. More precisely, \p count returns the number of iterators \c i in | |
| * <tt>[first, last)</tt> such that <tt>*i == value</tt>. | |
| * | |
| * \param first The beginning of the sequence. | |
| * \param last The end of the sequence. | |
| * \param value The value to be counted. | |
| * \return The number of elements equal to \p value. | |
| * | |
| * \tparam InputIterator must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator's \c value_type must be a model of must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/equality_comparable">Equality Comparable</a>. | |
| * \tparam EqualityComparable must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/equality_comparable">Equality Comparable</a> and can be compared for equality with \c InputIterator's \c value_type | |
| * | |
| * The following code snippet demonstrates how to use \p count to | |
| * count the number of instances in a range of a value of interest. | |
| * \code | |
| * #include <thrust/count.h> | |
| * #include <thrust/device_vector.h> | |
| * ... | |
| * // put 3 1s in a device_vector | |
| * thrust::device_vector<int> vec(5,0); | |
| * vec[1] = 1; | |
| * vec[3] = 1; | |
| * vec[4] = 1; | |
| * | |
| * // count the 1s | |
| * int result = thrust::count(vec.begin(), vec.end(), 1); | |
| * // result == 3 | |
| * \endcode | |
| * | |
| * \see https://en.cppreference.com/w/cpp/algorithm/count | |
| */ | |
| template <typename InputIterator, typename EqualityComparable> | |
| typename thrust::iterator_traits<InputIterator>::difference_type | |
| count(InputIterator first, InputIterator last, const EqualityComparable& value); | |
| /*! \p count_if finds the number of elements in <tt>[first,last)</tt> for which | |
| * a predicate is \c true. More precisely, \p count_if returns the number of iterators | |
| * \c i in <tt>[first, last)</tt> such that <tt>pred(*i) == true</tt>. | |
| * | |
| * The algorithm's execution is parallelized as determined by \p exec. | |
| * | |
| * \param exec The execution policy to use for parallelization. | |
| * \param first The beginning of the sequence. | |
| * \param last The end of the sequence. | |
| * \param pred The predicate. | |
| * \return The number of elements where \p pred is \c true. | |
| * | |
| * \tparam DerivedPolicy The name of the derived execution policy. | |
| * \tparam InputIterator must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator's \c value_type must be convertible to \c Predicate's \c argument_type. | |
| * \tparam Predicate must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/predicate">Predicate</a>. | |
| * | |
| * The following code snippet demonstrates how to use \p count to | |
| * count the number of odd numbers in a range using the \p thrust::device execution policy: | |
| * | |
| * \code | |
| * #include <thrust/count.h> | |
| * #include <thrust/device_vector.h> | |
| * #include <thrust/execution_policy.h> | |
| * ... | |
| * struct is_odd | |
| * { | |
| * __host__ __device__ | |
| * bool operator()(int &x) | |
| * { | |
| * return x & 1; | |
| * } | |
| * }; | |
| * ... | |
| * // fill a device_vector with even & odd numbers | |
| * thrust::device_vector<int> vec(5); | |
| * vec[0] = 0; | |
| * vec[1] = 1; | |
| * vec[2] = 2; | |
| * vec[3] = 3; | |
| * vec[4] = 4; | |
| * | |
| * // count the odd elements in vec | |
| * int result = thrust::count_if(thrust::device, vec.begin(), vec.end(), is_odd()); | |
| * // result == 2 | |
| * \endcode | |
| * | |
| * \see https://en.cppreference.com/w/cpp/algorithm/count | |
| */ | |
| template<typename DerivedPolicy, typename InputIterator, typename Predicate> | |
| __host__ __device__ | |
| typename thrust::iterator_traits<InputIterator>::difference_type | |
| count_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec, InputIterator first, InputIterator last, Predicate pred); | |
| /*! \p count_if finds the number of elements in <tt>[first,last)</tt> for which | |
| * a predicate is \c true. More precisely, \p count_if returns the number of iterators | |
| * \c i in <tt>[first, last)</tt> such that <tt>pred(*i) == true</tt>. | |
| * | |
| * \param first The beginning of the sequence. | |
| * \param last The end of the sequence. | |
| * \param pred The predicate. | |
| * \return The number of elements where \p pred is \c true. | |
| * | |
| * \tparam InputIterator must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator's \c value_type must be convertible to \c Predicate's \c argument_type. | |
| * \tparam Predicate must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/predicate">Predicate</a>. | |
| * | |
| * The following code snippet demonstrates how to use \p count to | |
| * count the number of odd numbers in a range. | |
| * \code | |
| * #include <thrust/count.h> | |
| * #include <thrust/device_vector.h> | |
| * ... | |
| * struct is_odd | |
| * { | |
| * __host__ __device__ | |
| * bool operator()(int &x) | |
| * { | |
| * return x & 1; | |
| * } | |
| * }; | |
| * ... | |
| * // fill a device_vector with even & odd numbers | |
| * thrust::device_vector<int> vec(5); | |
| * vec[0] = 0; | |
| * vec[1] = 1; | |
| * vec[2] = 2; | |
| * vec[3] = 3; | |
| * vec[4] = 4; | |
| * | |
| * // count the odd elements in vec | |
| * int result = thrust::count_if(vec.begin(), vec.end(), is_odd()); | |
| * // result == 2 | |
| * \endcode | |
| * | |
| * \see https://en.cppreference.com/w/cpp/algorithm/count | |
| */ | |
| template <typename InputIterator, typename Predicate> | |
| typename thrust::iterator_traits<InputIterator>::difference_type | |
| count_if(InputIterator first, InputIterator last, Predicate pred); | |
| /*! \} // end counting | |
| * \} // end reductions | |
| */ | |
| THRUST_NAMESPACE_END | |