56fd68e7dd
CCCL (CUDA C++ Core Libraries) provides: - CUB: device/block/warp-level GPU primitives (reduce, scan, sort, topk) - Thrust: high-level parallel algorithms (transform_reduce, sort, scan) - libcudacxx: CUDA C++ standard library (atomics, barriers, memory) - cudax: experimental features (memory resources, allocators) - Tuning policies: per-SM hardware-specific algorithm parameters Competition optimization vectors mapped to CCCL: - Output TPS (83% weight): warp_reduce, block_reduce, device_topk - Input TPS (14% weight): device_scan, block_load, prefetch - Cache TPS (3% weight): prefix caching strategy patterns - Memory (0.9 util): pooled/cached/buddy allocators Source: https://github.com/NVIDIA/cccl (shallow clone, HEAD only) License: Apache-2.0
476 lines
22 KiB
C++
476 lines
22 KiB
C++
// SPDX-FileCopyrightText: Copyright (c) 2008-2013, NVIDIA Corporation. All rights reserved.
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// SPDX-License-Identifier: Apache-2.0
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/*! \file gather.h
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* \brief Irregular copying from a source range
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*/
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#pragma once
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#include <thrust/detail/config.h>
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#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
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# pragma GCC system_header
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#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
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# pragma clang system_header
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#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
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# pragma system_header
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#endif // no system header
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#include <thrust/detail/execution_policy.h>
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THRUST_NAMESPACE_BEGIN
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/*! \addtogroup gathering
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* \ingroup copying
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* \{
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*/
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/*! \p gather copies elements from a source array into a destination range according
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* to a map. For each input iterator \c i in the range <tt>[map_first, map_last)</tt>, the
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* value <tt>input_first[\*i]</tt> is assigned to <tt>*(result + (i - map_first))</tt>.
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* \p RandomAccessIterator must permit random access.
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*
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* The algorithm's execution is parallelized as determined by \p exec.
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*
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* \param exec The execution policy to use for parallelization.
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* \param map_first Beginning of the range of gather locations.
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* \param map_last End of the range of gather locations.
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* \param input_first Beginning of the source range.
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* \param result Beginning of the destination range.
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*
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* \tparam DerivedPolicy The name of the derived execution policy.
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* \tparam InputIterator must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input
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* Iterator</a> and \c InputIterator's \c value_type must be convertible to \c RandomAccessIterator's \c
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* difference_type. \tparam RandomAccessIterator must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/random_access_iterator">Random Access Iterator</a> and \c
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* RandomAccessIterator's \c value_type must be convertible to \c OutputIterator's \c value_type. \tparam OutputIterator
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* must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/output_iterator">Output Iterator</a>.
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*
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* \pre The range <tt>[map_first, map_last)</tt> shall not overlap the range <tt>[result, result + (map_last -
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* map_first))</tt>. \pre The input data shall not overlap the range <tt>[result, result + (map_last - map_first))</tt>.
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*
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* \remark \p gather is the inverse of thrust::scatter.
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*
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* The following code snippet demonstrates how to use \p gather to reorder
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* a range using the \p thrust::device execution policy for parallelization:
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*
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* \code
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* #include <thrust/gather.h>
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* #include <thrust/device_vector.h>
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* #include <thrust/execution_policy.h>
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* ...
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* // mark even indices with a 1; odd indices with a 0
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* int values[10] = {1, 0, 1, 0, 1, 0, 1, 0, 1, 0};
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* thrust::device_vector<int> d_values(values, values + 10);
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*
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* // gather all even indices into the first half of the range
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* // and odd indices to the last half of the range
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* int map[10] = {0, 2, 4, 6, 8, 1, 3, 5, 7, 9};
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* thrust::device_vector<int> d_map(map, map + 10);
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*
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* thrust::device_vector<int> d_output(10);
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* thrust::gather(thrust::device,
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* d_map.begin(), d_map.end(),
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* d_values.begin(),
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* d_output.begin());
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* // d_output is now {1, 1, 1, 1, 1, 0, 0, 0, 0, 0}
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* \endcode
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*
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* \verbatim embed:rst:leading-asterisk
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* .. versionadded:: 2.2.0
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* \endverbatim
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*/
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template <typename DerivedPolicy, typename InputIterator, typename RandomAccessIterator, typename OutputIterator>
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_CCCL_HOST_DEVICE OutputIterator gather(
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const thrust::detail::execution_policy_base<DerivedPolicy>& exec,
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InputIterator map_first,
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InputIterator map_last,
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RandomAccessIterator input_first,
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OutputIterator result);
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/*! \p gather copies elements from a source array into a destination range according
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* to a map. For each input iterator \c i in the range <tt>[map_first, map_last)</tt>, the
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* value <tt>input_first[\*i]</tt> is assigned to <tt>*(result + (i - map_first))</tt>.
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* \p RandomAccessIterator must permit random access.
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*
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* \param map_first Beginning of the range of gather locations.
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* \param map_last End of the range of gather locations.
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* \param input_first Beginning of the source range.
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* \param result Beginning of the destination range.
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*
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* \tparam InputIterator must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input
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* Iterator</a> and \c InputIterator's \c value_type must be convertible to \c RandomAccessIterator's \c
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* difference_type. \tparam RandomAccessIterator must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/random_access_iterator">Random Access Iterator</a> and \c
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* RandomAccessIterator's \c value_type must be convertible to \c OutputIterator's \c value_type. \tparam OutputIterator
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* must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/output_iterator">Output Iterator</a>.
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*
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* \pre The range <tt>[map_first, map_last)</tt> shall not overlap the range <tt>[result, result + (map_last -
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* map_first))</tt>. \pre The input data shall not overlap the range <tt>[result, result + (map_last - map_first))</tt>.
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*
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* \remark \p gather is the inverse of thrust::scatter.
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*
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* The following code snippet demonstrates how to use \p gather to reorder
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* a range.
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*
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* \code
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* #include <thrust/gather.h>
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* #include <thrust/device_vector.h>
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* ...
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* // mark even indices with a 1; odd indices with a 0
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* int values[10] = {1, 0, 1, 0, 1, 0, 1, 0, 1, 0};
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* thrust::device_vector<int> d_values(values, values + 10);
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*
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* // gather all even indices into the first half of the range
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* // and odd indices to the last half of the range
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* int map[10] = {0, 2, 4, 6, 8, 1, 3, 5, 7, 9};
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* thrust::device_vector<int> d_map(map, map + 10);
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*
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* thrust::device_vector<int> d_output(10);
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* thrust::gather(d_map.begin(), d_map.end(),
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* d_values.begin(),
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* d_output.begin());
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* // d_output is now {1, 1, 1, 1, 1, 0, 0, 0, 0, 0}
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* \endcode
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*
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* \verbatim embed:rst:leading-asterisk
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* .. versionadded:: 2.2.0
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* \endverbatim
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*/
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template <typename InputIterator, typename RandomAccessIterator, typename OutputIterator>
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OutputIterator
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gather(InputIterator map_first, InputIterator map_last, RandomAccessIterator input_first, OutputIterator result);
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/*! \p gather_if conditionally copies elements from a source array into a destination
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* range according to a map. For each input iterator \c i in the range <tt>[map_first, map_last)</tt>,
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* such that the value of <tt>\*(stencil + (i - map_first))</tt> is \c true, the value
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* <tt>input_first[\*i]</tt> is assigned to <tt>*(result + (i - map_first))</tt>.
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* \p RandomAccessIterator must permit random access.
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*
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* The algorithm's execution is parallelized as determined by \p exec.
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*
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* \param exec The execution policy to use for parallelization.
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* \param map_first Beginning of the range of gather locations.
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* \param map_last End of the range of gather locations.
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* \param stencil Beginning of the range of predicate values.
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* \param input_first Beginning of the source range.
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* \param result Beginning of the destination range.
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*
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* \tparam DerivedPolicy The name of the derived execution policy.
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* \tparam InputIterator1 must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input
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* Iterator</a> and \c InputIterator1's \c value_type must be convertible to \c RandomAccessIterator's \c
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* difference_type. \tparam InputIterator2 must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator2's \c
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* value_type must be convertible to \c bool. \tparam RandomAccessIterator must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/random_access_iterator">Random Access iterator</a> and \c
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* RandomAccessIterator's \c value_type must be convertible to \c OutputIterator's \c value_type. \tparam OutputIterator
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* must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/output_iterator">Output Iterator</a>.
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*
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* \pre The range <tt>[map_first, map_last)</tt> shall not overlap the range <tt>[result, result + (map_last -
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* map_first))</tt>. \pre The range <tt>[stencil, stencil + (map_last - map_first))</tt> shall not overlap the range
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* <tt>[result, result + (map_last - map_first))</tt>. \pre The input data shall not overlap the range <tt>[result,
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* result + (map_last - map_first))</tt>.
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*
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* \remark \p gather_if is the inverse of \p scatter_if.
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*
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* The following code snippet demonstrates how to use \p gather_if to gather selected values from
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* an input range using the \p thrust::device execution policy:
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*
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* \code
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* #include <thrust/gather.h>
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* #include <thrust/device_vector.h>
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* #include <thrust/execution_policy.h>
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* ...
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*
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* int values[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
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* thrust::device_vector<int> d_values(values, values + 10);
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*
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* // select elements at even-indexed locations
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* int stencil[10] = {1, 0, 1, 0, 1, 0, 1, 0, 1, 0};
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* thrust::device_vector<int> d_stencil(stencil, stencil + 10);
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*
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* // map all even indices into the first half of the range
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* // and odd indices to the last half of the range
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* int map[10] = {0, 2, 4, 6, 8, 1, 3, 5, 7, 9};
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* thrust::device_vector<int> d_map(map, map + 10);
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*
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* thrust::device_vector<int> d_output(10, 7);
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* thrust::gather_if(thrust::device,
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* d_map.begin(), d_map.end(),
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* d_stencil.begin(),
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* d_values.begin(),
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* d_output.begin());
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* // d_output is now {0, 7, 4, 7, 8, 7, 3, 7, 7, 7}
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* \endcode
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*
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* \verbatim embed:rst:leading-asterisk
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* .. versionadded:: 2.2.0
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* \endverbatim
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*/
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template <typename DerivedPolicy,
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typename InputIterator1,
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typename InputIterator2,
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typename RandomAccessIterator,
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typename OutputIterator>
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_CCCL_HOST_DEVICE OutputIterator gather_if(
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const thrust::detail::execution_policy_base<DerivedPolicy>& exec,
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InputIterator1 map_first,
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InputIterator1 map_last,
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InputIterator2 stencil,
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RandomAccessIterator input_first,
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OutputIterator result);
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/*! \p gather_if conditionally copies elements from a source array into a destination
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* range according to a map. For each input iterator \c i in the range <tt>[map_first, map_last)</tt>,
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* such that the value of <tt>\*(stencil + (i - map_first))</tt> is \c true, the value
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* <tt>input_first[\*i]</tt> is assigned to <tt>*(result + (i - map_first))</tt>.
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* \p RandomAccessIterator must permit random access.
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*
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* \param map_first Beginning of the range of gather locations.
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* \param map_last End of the range of gather locations.
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* \param stencil Beginning of the range of predicate values.
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* \param input_first Beginning of the source range.
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* \param result Beginning of the destination range.
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*
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* \tparam InputIterator1 must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input
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* Iterator</a> and \c InputIterator1's \c value_type must be convertible to \c RandomAccessIterator's \c
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* difference_type. \tparam InputIterator2 must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator2's \c
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* value_type must be convertible to \c bool. \tparam RandomAccessIterator must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/random_access_iterator">Random Access iterator</a> and \c
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* RandomAccessIterator's \c value_type must be convertible to \c OutputIterator's \c value_type. \tparam OutputIterator
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* must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/output_iterator">Output Iterator</a>.
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*
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* \pre The range <tt>[map_first, map_last)</tt> shall not overlap the range <tt>[result, result + (map_last -
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* map_first))</tt>. \pre The range <tt>[stencil, stencil + (map_last - map_first))</tt> shall not overlap the range
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* <tt>[result, result + (map_last - map_first))</tt>. \pre The input data shall not overlap the range <tt>[result,
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* result + (map_last - map_first))</tt>.
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*
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* \remark \p gather_if is the inverse of \p scatter_if.
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*
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* The following code snippet demonstrates how to use \p gather_if to gather selected values from
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* an input range.
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*
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* \code
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* #include <thrust/gather.h>
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* #include <thrust/device_vector.h>
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* ...
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*
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* int values[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
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* thrust::device_vector<int> d_values(values, values + 10);
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*
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* // select elements at even-indexed locations
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* int stencil[10] = {1, 0, 1, 0, 1, 0, 1, 0, 1, 0};
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* thrust::device_vector<int> d_stencil(stencil, stencil + 10);
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*
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* // map all even indices into the first half of the range
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* // and odd indices to the last half of the range
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* int map[10] = {0, 2, 4, 6, 8, 1, 3, 5, 7, 9};
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* thrust::device_vector<int> d_map(map, map + 10);
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*
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* thrust::device_vector<int> d_output(10, 7);
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* thrust::gather_if(d_map.begin(), d_map.end(),
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* d_stencil.begin(),
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* d_values.begin(),
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* d_output.begin());
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* // d_output is now {0, 7, 4, 7, 8, 7, 3, 7, 7, 7}
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* \endcode
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*
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* \verbatim embed:rst:leading-asterisk
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* .. versionadded:: 2.2.0
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* \endverbatim
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*/
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template <typename InputIterator1, typename InputIterator2, typename RandomAccessIterator, typename OutputIterator>
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OutputIterator gather_if(
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InputIterator1 map_first,
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InputIterator1 map_last,
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InputIterator2 stencil,
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RandomAccessIterator input_first,
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OutputIterator result);
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/*! \p gather_if conditionally copies elements from a source array into a destination
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* range according to a map. For each input iterator \c i in the range <tt>[map_first, map_last)</tt>
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* such that the value of <tt>pred(\*(stencil + (i - map_first)))</tt> is \c true,
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* the value <tt>input_first[\*i]</tt> is assigned to <tt>*(result + (i - map_first))</tt>.
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* \p RandomAccessIterator must permit random access.
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*
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* The algorithm's execution is parallelized as determined by \p exec.
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*
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* \param exec The execution policy to use for parallelization.
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* \param map_first Beginning of the range of gather locations.
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* \param map_last End of the range of gather locations.
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* \param stencil Beginning of the range of predicate values.
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* \param input_first Beginning of the source range.
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* \param result Beginning of the destination range.
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* \param pred Predicate to apply to the stencil values.
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*
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* \tparam DerivedPolicy The name of the derived execution policy.
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* \tparam InputIterator1 must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input
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* Iterator</a> and \c InputIterator1's \c value_type must be convertible to \c RandomAccessIterator's \c
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* difference_type. \tparam InputIterator2 must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator2's \c
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* value_type must be convertible to \c Predicate's argument type. \tparam RandomAccessIterator must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/random_access_iterator">Random Access iterator</a> and \c
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* RandomAccessIterator's \c value_type must be convertible to \c OutputIterator's \c value_type. \tparam OutputIterator
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* must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/output_iterator">Output Iterator</a>. \tparam
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* Predicate must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/predicate">Predicate</a>.
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*
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* \pre The range <tt>[map_first, map_last)</tt> shall not overlap the range <tt>[result, result + (map_last -
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* map_first))</tt>. \pre The range <tt>[stencil, stencil + (map_last - map_first))</tt> shall not overlap the range
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* <tt>[result, result + (map_last - map_first))</tt>. \pre The input data shall not overlap the range <tt>[result,
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* result + (map_last - map_first))</tt>.
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*
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* \remark \p gather_if is the inverse of \p scatter_if.
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*
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* The following code snippet demonstrates how to use \p gather_if to gather selected values from
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* an input range based on an arbitrary selection function using the \p thrust::device execution policy for
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* parallelization:
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*
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* \code
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* #include <thrust/gather.h>
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* #include <thrust/device_vector.h>
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* #include <thrust/execution_policy.h>
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*
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* struct is_even
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* {
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* __host__ __device__
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* bool operator()(const int x)
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* {
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* return (x % 2) == 0;
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* }
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* };
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* ...
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*
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* int values[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
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* thrust::device_vector<int> d_values(values, values + 10);
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*
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* // we will select an element when our stencil is even
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* int stencil[10] = {0, 3, 4, 1, 4, 1, 2, 7, 8, 9};
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* thrust::device_vector<int> d_stencil(stencil, stencil + 10);
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*
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* // map all even indices into the first half of the range
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* // and odd indices to the last half of the range
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* int map[10] = {0, 2, 4, 6, 8, 1, 3, 5, 7, 9};
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* thrust::device_vector<int> d_map(map, map + 10);
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*
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* thrust::device_vector<int> d_output(10, 7);
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* thrust::gather_if(thrust::device,
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* d_map.begin(), d_map.end(),
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* d_stencil.begin(),
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* d_values.begin(),
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* d_output.begin(),
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* is_even());
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* // d_output is now {0, 7, 4, 7, 8, 7, 3, 7, 7, 7}
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* \endcode
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*
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* \verbatim embed:rst:leading-asterisk
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* .. versionadded:: 2.2.0
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* \endverbatim
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*/
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template <typename DerivedPolicy,
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typename InputIterator1,
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typename InputIterator2,
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typename RandomAccessIterator,
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typename OutputIterator,
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typename Predicate>
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_CCCL_HOST_DEVICE OutputIterator gather_if(
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const thrust::detail::execution_policy_base<DerivedPolicy>& exec,
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InputIterator1 map_first,
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InputIterator1 map_last,
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InputIterator2 stencil,
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RandomAccessIterator input_first,
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OutputIterator result,
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Predicate pred);
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/*! \p gather_if conditionally copies elements from a source array into a destination
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* range according to a map. For each input iterator \c i in the range <tt>[map_first, map_last)</tt>
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* such that the value of <tt>pred(\*(stencil + (i - map_first)))</tt> is \c true,
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* the value <tt>input_first[\*i]</tt> is assigned to <tt>*(result + (i - map_first))</tt>.
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* \p RandomAccessIterator must permit random access.
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*
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* \param map_first Beginning of the range of gather locations.
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* \param map_last End of the range of gather locations.
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* \param stencil Beginning of the range of predicate values.
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* \param input_first Beginning of the source range.
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* \param result Beginning of the destination range.
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* \param pred Predicate to apply to the stencil values.
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*
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* \tparam InputIterator1 must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input
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* Iterator</a> and \c InputIterator1's \c value_type must be convertible to \c RandomAccessIterator's \c
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* difference_type. \tparam InputIterator2 must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/input_iterator">Input Iterator</a> and \c InputIterator2's \c
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* value_type must be convertible to \c Predicate's argument type. \tparam RandomAccessIterator must be a model of <a
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* href="https://en.cppreference.com/w/cpp/iterator/random_access_iterator">Random Access iterator</a> and \c
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* RandomAccessIterator's \c value_type must be convertible to \c OutputIterator's \c value_type. \tparam OutputIterator
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* must be a model of <a href="https://en.cppreference.com/w/cpp/iterator/output_iterator">Output Iterator</a>. \tparam
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* Predicate must be a model of <a href="https://en.cppreference.com/w/cpp/concepts/predicate">Predicate</a>.
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*
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* \pre The range <tt>[map_first, map_last)</tt> shall not overlap the range <tt>[result, result + (map_last -
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* map_first))</tt>. \pre The range <tt>[stencil, stencil + (map_last - map_first))</tt> shall not overlap the range
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* <tt>[result, result + (map_last - map_first))</tt>. \pre The input data shall not overlap the range <tt>[result,
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* result + (map_last - map_first))</tt>.
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*
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* \remark \p gather_if is the inverse of \p scatter_if.
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*
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* The following code snippet demonstrates how to use \p gather_if to gather selected values from
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* an input range based on an arbitrary selection function.
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*
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* \code
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* #include <thrust/gather.h>
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* #include <thrust/device_vector.h>
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*
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* struct is_even
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* {
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* __host__ __device__
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* bool operator()(const int x)
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* {
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* return (x % 2) == 0;
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* }
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* };
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* ...
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*
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* int values[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
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* thrust::device_vector<int> d_values(values, values + 10);
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*
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* // we will select an element when our stencil is even
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* int stencil[10] = {0, 3, 4, 1, 4, 1, 2, 7, 8, 9};
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* thrust::device_vector<int> d_stencil(stencil, stencil + 10);
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*
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* // map all even indices into the first half of the range
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* // and odd indices to the last half of the range
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* int map[10] = {0, 2, 4, 6, 8, 1, 3, 5, 7, 9};
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* thrust::device_vector<int> d_map(map, map + 10);
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*
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* thrust::device_vector<int> d_output(10, 7);
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* thrust::gather_if(d_map.begin(), d_map.end(),
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* d_stencil.begin(),
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* d_values.begin(),
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* d_output.begin(),
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* is_even());
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* // d_output is now {0, 7, 4, 7, 8, 7, 3, 7, 7, 7}
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* \endcode
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*
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* \verbatim embed:rst:leading-asterisk
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* .. versionadded:: 2.2.0
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* \endverbatim
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*/
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template <typename InputIterator1,
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typename InputIterator2,
|
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typename RandomAccessIterator,
|
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typename OutputIterator,
|
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typename Predicate>
|
|
OutputIterator gather_if(
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InputIterator1 map_first,
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InputIterator1 map_last,
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InputIterator2 stencil,
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RandomAccessIterator input_first,
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OutputIterator result,
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Predicate pred);
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/*! \} // gathering
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*/
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THRUST_NAMESPACE_END
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#include <thrust/detail/gather.inl>
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