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506 lines
21 KiB
506 lines
21 KiB
11 years ago
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/*
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* Copyright 2008-2012 NVIDIA Corporation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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/*! \file copy.h
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* \brief Copies elements from one range to another
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*/
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#pragma once
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#include <thrust/detail/config.h>
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#include <thrust/detail/execution_policy.h>
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namespace thrust
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{
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/*! \addtogroup algorithms
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*/
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/*! \addtogroup copying
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* \ingroup algorithms
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* \{
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*/
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/*! \p copy copies elements from the range [\p first, \p last) to the range
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* [\p result, \p result + (\p last - \p first)). That is, it performs
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* the assignments *\p result = *\p first, *(\p result + \c 1) = *(\p first + \c 1),
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* and so on. Generally, for every integer \c n from \c 0 to \p last - \p first, \p copy
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* performs the assignment *(\p result + \c n) = *(\p first + \c n). Unlike
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* \c std::copy, \p copy offers no guarantee on order of operation. As a result,
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* calling \p copy with overlapping source and destination ranges has undefined
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* behavior.
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*
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* The return value is \p result + (\p last - \p first).
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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 first The beginning of the sequence to copy.
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* \param last The end of the sequence to copy.
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* \param result The destination sequence.
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* \return The end of the destination sequence.
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* \see http://www.sgi.com/tech/stl/copy.html
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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="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a> and \c InputIterator's \c value_type must be convertible to \c OutputIterator's \c value_type.
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* \tparam OutputIterator must be a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
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*
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* \pre \p result may be equal to \p first, but \p result shall not be in the range <tt>[first, last)</tt> otherwise.
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*
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* The following code snippet demonstrates how to use \p copy
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* to copy from one range to another using the \p thrust::device parallelization policy:
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*
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* \code
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* #include <thrust/copy.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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* thrust::device_vector<int> vec0(100);
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* thrust::device_vector<int> vec1(100);
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* ...
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*
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* thrust::copy(thrust::device, vec0.begin(), vec0.end(), vec1.begin());
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*
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* // vec1 is now a copy of vec0
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* \endcode
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*/
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template<typename DerivedPolicy, typename InputIterator, typename OutputIterator>
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OutputIterator copy(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
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InputIterator first,
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InputIterator last,
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OutputIterator result);
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/*! \p copy_n copies elements from the range <tt>[first, first + n)</tt> to the range
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* <tt>[result, result + n)</tt>. That is, it performs the assignments <tt>*result = *first, *(result + 1) = *(first + 1)</tt>,
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* and so on. Generally, for every integer \c i from \c 0 to \c n, \p copy
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* performs the assignment *(\p result + \c i) = *(\p first + \c i). Unlike
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* \c std::copy_n, \p copy_n offers no guarantee on order of operation. As a result,
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* calling \p copy_n with overlapping source and destination ranges has undefined
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* behavior.
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*
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* The return value is \p result + \p n.
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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 first The beginning of the range to copy.
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* \param n The number of elements to copy.
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* \param result The beginning destination range.
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* \return The end 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="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a> and \c InputIterator's \c value_type must be convertible to \c OutputIterator's \c value_type.
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* \tparam Size is an integral type.
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* \tparam OutputIterator must be a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
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*
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* \pre \p result may be equal to \p first, but \p result shall not be in the range <tt>[first, first + n)</tt> otherwise.
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*
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* The following code snippet demonstrates how to use \p copy
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* to copy from one range to another using the \p thrust::device parallelization policy:
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*
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* \code
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* #include <thrust/copy.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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* size_t n = 100;
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* thrust::device_vector<int> vec0(n);
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* thrust::device_vector<int> vec1(n);
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* ...
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* thrust::copy_n(thrust::device, vec0.begin(), n, vec1.begin());
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*
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* // vec1 is now a copy of vec0
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* \endcode
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*
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* \see http://www.sgi.com/tech/stl/copy_n.html
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* \see thrust::copy
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*/
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template<typename DerivedPolicy, typename InputIterator, typename Size, typename OutputIterator>
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OutputIterator copy_n(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
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InputIterator first,
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Size n,
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OutputIterator result);
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/*! \p copy copies elements from the range [\p first, \p last) to the range
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* [\p result, \p result + (\p last - \p first)). That is, it performs
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* the assignments *\p result = *\p first, *(\p result + \c 1) = *(\p first + \c 1),
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* and so on. Generally, for every integer \c n from \c 0 to \p last - \p first, \p copy
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* performs the assignment *(\p result + \c n) = *(\p first + \c n). Unlike
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* \c std::copy, \p copy offers no guarantee on order of operation. As a result,
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* calling \p copy with overlapping source and destination ranges has undefined
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* behavior.
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*
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* The return value is \p result + (\p last - \p first).
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*
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* \param first The beginning of the sequence to copy.
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* \param last The end of the sequence to copy.
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* \param result The destination sequence.
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* \return The end of the destination sequence.
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* \see http://www.sgi.com/tech/stl/copy.html
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*
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* \tparam InputIterator must be a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a> and \c InputIterator's \c value_type must be convertible to \c OutputIterator's \c value_type.
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* \tparam OutputIterator must be a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
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*
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* \pre \p result may be equal to \p first, but \p result shall not be in the range <tt>[first, last)</tt> otherwise.
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*
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* The following code snippet demonstrates how to use \p copy
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* to copy from one range to another.
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*
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* \code
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* #include <thrust/copy.h>
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* #include <thrust/device_vector.h>
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* ...
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*
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* thrust::device_vector<int> vec0(100);
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* thrust::device_vector<int> vec1(100);
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* ...
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*
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* thrust::copy(vec0.begin(), vec0.end(),
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* vec1.begin());
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*
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* // vec1 is now a copy of vec0
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* \endcode
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*/
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template<typename InputIterator, typename OutputIterator>
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OutputIterator copy(InputIterator first,
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InputIterator last,
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OutputIterator result);
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/*! \p copy_n copies elements from the range <tt>[first, first + n)</tt> to the range
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* <tt>[result, result + n)</tt>. That is, it performs the assignments <tt>*result = *first, *(result + 1) = *(first + 1)</tt>,
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* and so on. Generally, for every integer \c i from \c 0 to \c n, \p copy
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* performs the assignment *(\p result + \c i) = *(\p first + \c i). Unlike
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* \c std::copy_n, \p copy_n offers no guarantee on order of operation. As a result,
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* calling \p copy_n with overlapping source and destination ranges has undefined
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* behavior.
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*
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* The return value is \p result + \p n.
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*
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* \param first The beginning of the range to copy.
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* \param n The number of elements to copy.
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* \param result The beginning destination range.
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* \return The end of the destination range.
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*
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* \tparam InputIterator must be a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a> and \c InputIterator's \c value_type must be convertible to \c OutputIterator's \c value_type.
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* \tparam Size is an integral type.
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* \tparam OutputIterator must be a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
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*
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* \pre \p result may be equal to \p first, but \p result shall not be in the range <tt>[first, first + n)</tt> otherwise.
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*
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* The following code snippet demonstrates how to use \p copy
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* to copy from one range to another.
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*
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* \code
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* #include <thrust/copy.h>
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* #include <thrust/device_vector.h>
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* ...
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* size_t n = 100;
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* thrust::device_vector<int> vec0(n);
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* thrust::device_vector<int> vec1(n);
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* ...
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* thrust::copy_n(vec0.begin(), n, vec1.begin());
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*
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* // vec1 is now a copy of vec0
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* \endcode
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*
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* \see http://www.sgi.com/tech/stl/copy_n.html
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* \see thrust::copy
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*/
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template<typename InputIterator, typename Size, typename OutputIterator>
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OutputIterator copy_n(InputIterator first,
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Size n,
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OutputIterator result);
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/*! \} // end copying
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*/
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/*! \addtogroup stream_compaction
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* \{
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*/
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/*! This version of \p copy_if copies elements from the range <tt>[first,last)</tt>
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* to a range beginning at \ presult, except that any element which causes \p pred
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* to be \p pred to be \c false is not copied.
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*
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* More precisely, for every integer \c n such that <tt>0 <= n < last-first</tt>,
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* \p copy_if performs the assignment <tt>*result = *(first+n)</tt> and \p result
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* is advanced one position if <tt>pred(*(first+n))</tt>. Otherwise, no assignment
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* occurs and \p result is not advanced.
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*
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* The algorithm's execution is parallelized as determined by \p system.
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*
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* \param exec The execution policy to use for parallelization.
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* \param first The beginning of the sequence from which to copy.
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* \param last The end of the sequence from which to copy.
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* \param result The beginning of the sequence into which to copy.
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* \param pred The predicate to test on every value of the range <tt>[first, last)</tt>.
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* \return <tt>result + n</tt>, where \c n is equal to the number of times \p pred
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* evaluated to \c true in the range <tt>[first, last)</tt>.
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*
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* \tparam DerivedPolicy The name of the derived execution policy.
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* \tparam InputIterator is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>,
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* and \p InputIterator's \c value_type is convertible to \p Predicate's \c argument_type.
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* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
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* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
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*
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* \pre The ranges <tt>[first, last)</tt> and <tt>[result, result + (last - first))</tt> shall not overlap.
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*
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* The following code snippet demonstrates how to use \p copy_if to perform stream compaction
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* to copy even numbers to an output range using the \p thrust::host parallelization policy:
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*
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* \code
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* #include <thrust/copy.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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* const int N = 6;
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* int V[N] = {-2, 0, -1, 0, 1, 2};
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* int result[4];
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*
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* thrust::copy_if(thrust::host, V, V + N, result, is_even());
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*
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* // V remains {-2, 0, -1, 0, 1, 2}
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* // result is now {-2, 0, 0, 2}
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* \endcode
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*
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* \see \c remove_copy_if
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*/
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template<typename DerivedPolicy, typename InputIterator, typename OutputIterator, typename Predicate>
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OutputIterator copy_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
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InputIterator first,
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InputIterator last,
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OutputIterator result,
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Predicate pred);
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/*! This version of \p copy_if copies elements from the range <tt>[first,last)</tt>
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* to a range beginning at \ presult, except that any element which causes \p pred
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* to be \p pred to be \c false is not copied.
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*
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* More precisely, for every integer \c n such that <tt>0 <= n < last-first</tt>,
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* \p copy_if performs the assignment <tt>*result = *(first+n)</tt> and \p result
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* is advanced one position if <tt>pred(*(first+n))</tt>. Otherwise, no assignment
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* occurs and \p result is not advanced.
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*
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* \param first The beginning of the sequence from which to copy.
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* \param last The end of the sequence from which to copy.
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* \param result The beginning of the sequence into which to copy.
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* \param pred The predicate to test on every value of the range <tt>[first, last)</tt>.
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* \return <tt>result + n</tt>, where \c n is equal to the number of times \p pred
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* evaluated to \c true in the range <tt>[first, last)</tt>.
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*
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* \tparam InputIterator is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>,
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* and \p InputIterator's \c value_type is convertible to \p Predicate's \c argument_type.
|
||
|
|
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
|
||
|
|
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
|
||
|
|
*
|
||
|
|
* \pre The ranges <tt>[first, last)</tt> and <tt>[result, result + (last - first))</tt> shall not overlap.
|
||
|
|
*
|
||
|
|
* The following code snippet demonstrates how to use \p copy_if to perform stream compaction
|
||
|
|
* to copy even numbers to an output range.
|
||
|
|
*
|
||
|
|
* \code
|
||
|
|
* #include <thrust/copy.h>
|
||
|
|
* ...
|
||
|
|
* struct is_even
|
||
|
|
* {
|
||
|
|
* __host__ __device__
|
||
|
|
* bool operator()(const int x)
|
||
|
|
* {
|
||
|
|
* return (x % 2) == 0;
|
||
|
|
* }
|
||
|
|
* };
|
||
|
|
* ...
|
||
|
|
* const int N = 6;
|
||
|
|
* int V[N] = {-2, 0, -1, 0, 1, 2};
|
||
|
|
* int result[4];
|
||
|
|
*
|
||
|
|
* thrust::copy_if(V, V + N, result, is_even());
|
||
|
|
*
|
||
|
|
* // V remains {-2, 0, -1, 0, 1, 2}
|
||
|
|
* // result is now {-2, 0, 0, 2}
|
||
|
|
* \endcode
|
||
|
|
*
|
||
|
|
* \see \c remove_copy_if
|
||
|
|
*/
|
||
|
|
template<typename InputIterator,
|
||
|
|
typename OutputIterator,
|
||
|
|
typename Predicate>
|
||
|
|
OutputIterator copy_if(InputIterator first,
|
||
|
|
InputIterator last,
|
||
|
|
OutputIterator result,
|
||
|
|
Predicate pred);
|
||
|
|
|
||
|
|
|
||
|
|
/*! This version of \p copy_if copies elements from the range <tt>[first,last)</tt>
|
||
|
|
* to a range beginning at \p result, except that any element whose corresponding stencil
|
||
|
|
* element causes \p pred to be \c false is not copied.
|
||
|
|
*
|
||
|
|
* More precisely, for every integer \c n such that <tt>0 <= n < last-first</tt>,
|
||
|
|
* \p copy_if performs the assignment <tt>*result = *(first+n)</tt> and \p result
|
||
|
|
* is advanced one position if <tt>pred(*(stencil+n))</tt>. Otherwise, no assignment
|
||
|
|
* occurs and \p result is not advanced.
|
||
|
|
*
|
||
|
|
* 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 from which to copy.
|
||
|
|
* \param last The end of the sequence from which to copy.
|
||
|
|
* \param stencil The beginning of the stencil sequence.
|
||
|
|
* \param result The beginning of the sequence into which to copy.
|
||
|
|
* \param pred The predicate to test on every value of the range <tt>[stencil, stencil + (last-first))</tt>.
|
||
|
|
* \return <tt>result + n</tt>, where \c n is equal to the number of times \p pred
|
||
|
|
* evaluated to \c true in the range <tt>[stencil, stencil + (last-first))</tt>.
|
||
|
|
*
|
||
|
|
* \tparam DerivedPolicy The name of the derived execution policy.
|
||
|
|
* \tparam InputIterator1 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>.
|
||
|
|
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>,
|
||
|
|
* and \p InputIterator2's \c value_type is convertible to \p Predicate's \c argument_type.
|
||
|
|
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator">Output Iterator</a>.
|
||
|
|
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
|
||
|
|
*
|
||
|
|
* \pre The ranges <tt>[first, last)</tt> and <tt>[result, result + (last - first))</tt> shall not overlap.
|
||
|
|
* \pre The ranges <tt>[stencil, stencil + (last - first))</tt> and <tt>[result, result + (last - first))</tt> shall not overlap.
|
||
|
|
*
|
||
|
|
* The following code snippet demonstrates how to use \p copy_if to perform stream compaction
|
||
|
|
* to copy numbers to an output range when corresponding stencil elements are even using the \p thrust::host execution policy:
|
||
|
|
*
|
||
|
|
* \code
|
||
|
|
* #include <thrust/copy.h>
|
||
|
|
* #include <thrust/execution_policy.h>
|
||
|
|
* ...
|
||
|
|
* struct is_even
|
||
|
|
* {
|
||
|
|
* __host__ __device__
|
||
|
|
* bool operator()(const int x)
|
||
|
|
* {
|
||
|
|
* return (x % 2) == 0;
|
||
|
|
* }
|
||
|
|
* };
|
||
|
|
* ...
|
||
|
|
* int N = 6;
|
||
|
|
* int data[N] = { 0, 1, 2, 3, 4, 5};
|
||
|
|
* int stencil[N] = {-2, 0, -1, 0, 1, 2};
|
||
|
|
* int result[4];
|
||
|
|
*
|
||
|
|
* thrust::copy_if(thrust::host, data, data + N, stencil, result, is_even());
|
||
|
|
*
|
||
|
|
* // data remains = { 0, 1, 2, 3, 4, 5};
|
||
|
|
* // stencil remains = {-2, 0, -1, 0, 1, 2};
|
||
|
|
* // result is now { 0, 1, 3, 5}
|
||
|
|
* \endcode
|
||
|
|
*
|
||
|
|
* \see \c remove_copy_if
|
||
|
|
*/
|
||
|
|
template<typename DerivedPolicy, typename InputIterator1, typename InputIterator2, typename OutputIterator, typename Predicate>
|
||
|
|
OutputIterator copy_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
|
||
|
|
InputIterator1 first,
|
||
|
|
InputIterator1 last,
|
||
|
|
InputIterator2 stencil,
|
||
|
|
OutputIterator result,
|
||
|
|
Predicate pred);
|
||
|
|
|
||
|
|
|
||
|
|
/*! This version of \p copy_if copies elements from the range <tt>[first,last)</tt>
|
||
|
|
* to a range beginning at \p result, except that any element whose corresponding stencil
|
||
|
|
* element causes \p pred to be \c false is not copied.
|
||
|
|
*
|
||
|
|
* More precisely, for every integer \c n such that <tt>0 <= n < last-first</tt>,
|
||
|
|
* \p copy_if performs the assignment <tt>*result = *(first+n)</tt> and \p result
|
||
|
|
* is advanced one position if <tt>pred(*(stencil+n))</tt>. Otherwise, no assignment
|
||
|
|
* occurs and \p result is not advanced.
|
||
|
|
*
|
||
|
|
* \param first The beginning of the sequence from which to copy.
|
||
|
|
* \param last The end of the sequence from which to copy.
|
||
|
|
* \param stencil The beginning of the stencil sequence.
|
||
|
|
* \param result The beginning of the sequence into which to copy.
|
||
|
|
* \param pred The predicate to test on every value of the range <tt>[stencil, stencil + (last-first))</tt>.
|
||
|
|
* \return <tt>result + n</tt>, where \c n is equal to the number of times \p pred
|
||
|
|
* evaluated to \c true in the range <tt>[stencil, stencil + (last-first))</tt>.
|
||
|
|
*
|
||
|
|
* \tparam InputIterator1 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>.
|
||
|
|
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>,
|
||
|
|
* and \p InputIterator2's \c value_type is convertible to \p Predicate's \c argument_type.
|
||
|
|
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator">Output Iterator</a>.
|
||
|
|
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
|
||
|
|
*
|
||
|
|
* \pre The ranges <tt>[first, last)</tt> and <tt>[result, result + (last - first))</tt> shall not overlap.
|
||
|
|
* \pre The ranges <tt>[stencil, stencil + (last - first))</tt> and <tt>[result, result + (last - first))</tt> shall not overlap.
|
||
|
|
*
|
||
|
|
* The following code snippet demonstrates how to use \p copy_if to perform stream compaction
|
||
|
|
* to copy numbers to an output range when corresponding stencil elements are even:
|
||
|
|
*
|
||
|
|
* \code
|
||
|
|
* #include <thrust/copy.h>
|
||
|
|
* ...
|
||
|
|
* struct is_even
|
||
|
|
* {
|
||
|
|
* __host__ __device__
|
||
|
|
* bool operator()(const int x)
|
||
|
|
* {
|
||
|
|
* return (x % 2) == 0;
|
||
|
|
* }
|
||
|
|
* };
|
||
|
|
* ...
|
||
|
|
* int N = 6;
|
||
|
|
* int data[N] = { 0, 1, 2, 3, 4, 5};
|
||
|
|
* int stencil[N] = {-2, 0, -1, 0, 1, 2};
|
||
|
|
* int result[4];
|
||
|
|
*
|
||
|
|
* thrust::copy_if(data, data + N, stencil, result, is_even());
|
||
|
|
*
|
||
|
|
* // data remains = { 0, 1, 2, 3, 4, 5};
|
||
|
|
* // stencil remains = {-2, 0, -1, 0, 1, 2};
|
||
|
|
* // result is now { 0, 1, 3, 5}
|
||
|
|
* \endcode
|
||
|
|
*
|
||
|
|
* \see \c remove_copy_if
|
||
|
|
*/
|
||
|
|
template<typename InputIterator1,
|
||
|
|
typename InputIterator2,
|
||
|
|
typename OutputIterator,
|
||
|
|
typename Predicate>
|
||
|
|
OutputIterator copy_if(InputIterator1 first,
|
||
|
|
InputIterator1 last,
|
||
|
|
InputIterator2 stencil,
|
||
|
|
OutputIterator result,
|
||
|
|
Predicate pred);
|
||
|
|
|
||
|
|
/*! \} // end stream_compaction
|
||
|
|
*/
|
||
|
|
|
||
|
|
} // end namespace thrust
|
||
|
|
|
||
|
|
#include <thrust/detail/copy.h>
|
||
|
|
#include <thrust/detail/copy_if.h>
|
||
|
|
|