/*
* Copyright 2008-2012 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 transform.h
* \brief Transforms input ranges using a function object
*/
#pragma once
#include <thrust/detail/config.h>
#include <thrust/detail/execution_policy.h>
namespace thrust
{
/*! \addtogroup algorithms
*/
/*! \addtogroup transformations
* \ingroup algorithms
* \{
*/
/*! This version of \p transform applies a unary function to each element
* of an input sequence and stores the result in the corresponding
* position in an output sequence. Specifically, for each iterator
* <tt>i</tt> in the range [\p first, \p last) the operation
* <tt>op(*i)</tt> is performed and the result is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* [\p result, \p result + (\p last - \p first) ). The input and
* output sequences may coincide, resulting in an in-place transformation.
*
* 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 input sequence.
* \param last The end of the input sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \return The end of the output sequence.
*
* \tparam DerivedPolicy The name of the derived execution policy.
* \tparam InputIterator is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator's \c value_type is convertible to \c UnaryFunction's \c argument_type.
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
* \tparam UnaryFunction is a model of <a href="http://www.sgi.com/tech/stl/UnaryFunction.html">Unary Function</a>
* and \c UnaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
*
* \pre \p first may equal \p result, but the range <tt>[first, last)</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform to negate a range in-place
* using the \p thrust::host execution policy for parallelization:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
* #include <thrust/execution_policy.h>
* ...
*
* int data[10] = {-5, 0, 2, -3, 2, 4, 0, -1, 2, 8};
*
* thrust::negate<int> op;
*
* thrust::transform(thrust::host, data, data + 10, data, op); // in-place transformation
*
* // data is now {5, 0, -2, 3, -2, -4, 0, 1, -2, -8};
* \endcode
*
* \see http://www.sgi.com/tech/stl/transform.html
*/
template<typename DerivedPolicy,
typename InputIterator,
typename OutputIterator,
typename UnaryFunction>
OutputIterator transform(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
InputIterator first, InputIterator last,
OutputIterator result,
UnaryFunction op);
/*! This version of \p transform applies a unary function to each element
* of an input sequence and stores the result in the corresponding
* position in an output sequence. Specifically, for each iterator
* <tt>i</tt> in the range [\p first, \p last) the operation
* <tt>op(*i)</tt> is performed and the result is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* [\p result, \p result + (\p last - \p first) ). The input and
* output sequences may coincide, resulting in an in-place transformation.
*
* \param first The beginning of the input sequence.
* \param last The end of the input sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \return The end of the output sequence.
*
* \tparam InputIterator is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator's \c value_type is convertible to \c UnaryFunction's \c argument_type.
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
* \tparam UnaryFunction is a model of <a href="http://www.sgi.com/tech/stl/UnaryFunction.html">Unary Function</a>
* and \c UnaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
*
* \pre \p first may equal \p result, but the range <tt>[first, last)</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
*
* int data[10] = {-5, 0, 2, -3, 2, 4, 0, -1, 2, 8};
*
* thrust::negate<int> op;
*
* thrust::transform(data, data + 10, data, op); // in-place transformation
*
* // data is now {5, 0, -2, 3, -2, -4, 0, 1, -2, -8};
* \endcode
*
* \see http://www.sgi.com/tech/stl/transform.html
*/
template<typename InputIterator,
typename OutputIterator,
typename UnaryFunction>
OutputIterator transform(InputIterator first, InputIterator last,
OutputIterator result,
UnaryFunction op);
/*! This version of \p transform applies a binary function to each pair
* of elements from two input sequences and stores the result in the
* corresponding position in an output sequence. Specifically, for
* each iterator <tt>i</tt> in the range [\p first1, \p last1) and
* <tt>j = first + (i - first1)</tt> in the range [\p first2, \p last2)
* the operation <tt>op(*i,*j)</tt> is performed and the result is
* assigned to <tt>*o</tt>, where <tt>o</tt> is the corresponding
* output iterator in the range [\p result, \p result + (\p last - \p first) ).
* The input and output sequences may coincide, resulting in an
* in-place transformation.
*
* The algorithm's execution is parallelized as determined by \p exec.
*
* \param exec The execution policy to use for parallelization.
* \param first1 The beginning of the first input sequence.
* \param last1 The end of the first input sequence.
* \param first2 The beginning of the second input sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \return The end of the output sequence.
*
* \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>
* and \c InputIterator1's \c value_type is convertible to \c BinaryFunction's \c first_argument_type.
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator2's \c value_type is convertible to \c BinaryFunction's \c second_argument_type.
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
* \tparam BinaryFunction is a model of <a href="http://www.sgi.com/tech/stl/BinaryFunction.html">Binary Function</a>
* and \c BinaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
*
* \pre \p first1 may equal \p result, but the range <tt>[first1, last1)</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
* \pre \p first2 may equal \p result, but the range <tt>[first2, first2 + (last1 - first1))</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform to compute the sum of two
* ranges using the \p thrust::host execution policy for parallelization:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
* #include <thrust/execution_policy.h>
* ...
*
* int input1[6] = {-5, 0, 2, 3, 2, 4};
* int input2[6] = { 3, 6, -2, 1, 2, 3};
* int output[6];
*
* thrust::plus<int> op;
*
* thrust::transform(thrust::host, input1, input1 + 6, input2, output, op);
*
* // output is now {-2, 6, 0, 4, 4, 7};
* \endcode
*
* \see http://www.sgi.com/tech/stl/transform.html
*/
template<typename DerivedPolicy,
typename InputIterator1,
typename InputIterator2,
typename OutputIterator,
typename BinaryFunction>
OutputIterator transform(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2,
OutputIterator result,
BinaryFunction op);
/*! This version of \p transform applies a binary function to each pair
* of elements from two input sequences and stores the result in the
* corresponding position in an output sequence. Specifically, for
* each iterator <tt>i</tt> in the range [\p first1, \p last1) and
* <tt>j = first + (i - first1)</tt> in the range [\p first2, \p last2)
* the operation <tt>op(*i,*j)</tt> is performed and the result is
* assigned to <tt>*o</tt>, where <tt>o</tt> is the corresponding
* output iterator in the range [\p result, \p result + (\p last - \p first) ).
* The input and output sequences may coincide, resulting in an
* in-place transformation.
*
* \param first1 The beginning of the first input sequence.
* \param last1 The end of the first input sequence.
* \param first2 The beginning of the second input sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \return The end of the output sequence.
*
* \tparam InputIterator1 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator1's \c value_type is convertible to \c BinaryFunction's \c first_argument_type.
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator2's \c value_type is convertible to \c BinaryFunction's \c second_argument_type.
* \tparam OutputIterator is a model of <a href="http://www.sgi.com/tech/stl/OutputIterator.html">Output Iterator</a>.
* \tparam BinaryFunction is a model of <a href="http://www.sgi.com/tech/stl/BinaryFunction.html">Binary Function</a>
* and \c BinaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
*
* \pre \p first1 may equal \p result, but the range <tt>[first1, last1)</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
* \pre \p first2 may equal \p result, but the range <tt>[first2, first2 + (last1 - first1))</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
*
* int input1[6] = {-5, 0, 2, 3, 2, 4};
* int input2[6] = { 3, 6, -2, 1, 2, 3};
* int output[6];
*
* thrust::plus<int> op;
*
* thrust::transform(input1, input1 + 6, input2, output, op);
*
* // output is now {-2, 6, 0, 4, 4, 7};
* \endcode
*
* \see http://www.sgi.com/tech/stl/transform.html
*/
template<typename InputIterator1,
typename InputIterator2,
typename OutputIterator,
typename BinaryFunction>
OutputIterator transform(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2,
OutputIterator result,
BinaryFunction op);
/*! This version of \p transform_if conditionally applies a unary function
* to each element of an input sequence and stores the result in the corresponding
* position in an output sequence if the corresponding position in the input sequence
* satifies a predicate. Otherwise, the corresponding position in the
* output sequence is not modified.
*
* Specifically, for each iterator <tt>i</tt> in the range <tt>[first, last)</tt> the
* predicate <tt>pred(*i)</tt> is evaluated. If this predicate
* evaluates to \c true, the result of <tt>op(*i)</tt> is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* <tt>[result, result + (last - first) )</tt>. Otherwise, <tt>op(*i)</tt> is
* not evaluated and no assignment occurs. The input and output sequences may coincide,
* resulting in an in-place transformation.
*
* 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 input sequence.
* \param last The end of the input sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \param pred The predicate operation.
* \return The end of the output sequence.
*
* \tparam DerivedPolicy The name of the derived execution policy.
* \tparam InputIterator is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>,
* and \c InputIterator's \c value_type is convertible to \c Predicate's \c argument_type,
* and \c InputIterator's \c value_type is convertible to \c UnaryFunction's \c argument_type.
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>.
* \tparam UnaryFunction is a model of <a href="http://www.sgi.com/tech/stl/UnaryFunction.html">Unary Function</a>
* and \c UnaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
*
* \pre \p first may equal \p result, but the range <tt>[first, last)</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform_if to negate the odd-valued
* elements of a range using the \p thrust::host execution policy for parallelization:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
* #include <thrust/execution_policy.h>
* ...
*
* int data[10] = {-5, 0, 2, -3, 2, 4, 0, -1, 2, 8};
*
* struct is_odd
* {
* __host__ __device__
* bool operator()(int x)
* {
* return x % 2;
* }
* };
*
* thrust::negate<int> op;
* thrust::identity<int> identity;
*
* // negate odd elements
* thrust::transform_if(thrust::host, data, data + 10, data, op, is_odd()); // in-place transformation
*
* // data is now {5, 0, 2, 3, 2, 4, 0, 1, 2, 8};
* \endcode
*
* \see thrust::transform
*/
template<typename DerivedPolicy,
typename InputIterator,
typename ForwardIterator,
typename UnaryFunction,
typename Predicate>
ForwardIterator transform_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
InputIterator first, InputIterator last,
ForwardIterator result,
UnaryFunction op,
Predicate pred);
/*! This version of \p transform_if conditionally applies a unary function
* to each element of an input sequence and stores the result in the corresponding
* position in an output sequence if the corresponding position in the input sequence
* satifies a predicate. Otherwise, the corresponding position in the
* output sequence is not modified.
*
* Specifically, for each iterator <tt>i</tt> in the range <tt>[first, last)</tt> the
* predicate <tt>pred(*i)</tt> is evaluated. If this predicate
* evaluates to \c true, the result of <tt>op(*i)</tt> is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* <tt>[result, result + (last - first) )</tt>. Otherwise, <tt>op(*i)</tt> is
* not evaluated and no assignment occurs. The input and output sequences may coincide,
* resulting in an in-place transformation.
*
* \param first The beginning of the input sequence.
* \param last The end of the input sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \param pred The predicate operation.
* \return The end of the output sequence.
*
* \tparam InputIterator is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>,
* and \c InputIterator's \c value_type is convertible to \c Predicate's \c argument_type,
* and \c InputIterator's \c value_type is convertible to \c UnaryFunction's \c argument_type.
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>.
* \tparam UnaryFunction is a model of <a href="http://www.sgi.com/tech/stl/UnaryFunction.html">Unary Function</a>
* and \c UnaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
*
* \pre \p first may equal \p result, but the range <tt>[first, last)</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform_if:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
*
* int data[10] = {-5, 0, 2, -3, 2, 4, 0, -1, 2, 8};
*
* struct is_odd
* {
* __host__ __device__
* bool operator()(int x)
* {
* return x % 2;
* }
* };
*
* thrust::negate<int> op;
* thrust::identity<int> identity;
*
* // negate odd elements
* thrust::transform_if(data, data + 10, data, op, is_odd()); // in-place transformation
*
* // data is now {5, 0, 2, 3, 2, 4, 0, 1, 2, 8};
* \endcode
*
* \see thrust::transform
*/
template<typename InputIterator,
typename ForwardIterator,
typename UnaryFunction,
typename Predicate>
ForwardIterator transform_if(InputIterator first, InputIterator last,
ForwardIterator result,
UnaryFunction op,
Predicate pred);
/*! This version of \p transform_if conditionally applies a unary function
* to each element of an input sequence and stores the result in the corresponding
* position in an output sequence if the corresponding position in a stencil sequence
* satisfies a predicate. Otherwise, the corresponding position in the
* output sequence is not modified.
*
* Specifically, for each iterator <tt>i</tt> in the range <tt>[first, last)</tt> the
* predicate <tt>pred(*s)</tt> is evaluated, where <tt>s</tt> is the corresponding input
* iterator in the range <tt>[stencil, stencil + (last - first) )</tt>. If this predicate
* evaluates to \c true, the result of <tt>op(*i)</tt> is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* <tt>[result, result + (last - first) )</tt>. Otherwise, <tt>op(*i)</tt> is
* not evaluated and no assignment occurs. The input and output sequences may coincide,
* resulting in an in-place transformation.
*
* 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 input sequence.
* \param last The end of the input sequence.
* \param stencil The beginning of the stencil sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \param pred The predicate operation.
* \return The end of the output sequence.
*
* \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>
* and \c InputIterator1's \c value_type is convertible to \c UnaryFunction's \c argument_type.
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator2's \c value_type is convertible to \c Predicate's \c argument_type.
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>.
* \tparam UnaryFunction is a model of <a href="http://www.sgi.com/tech/stl/UnaryFunction.html">Unary Function</a>
* and \c UnaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
*
* \pre \p first may equal \p result, but the range <tt>[first, last)</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
* \pre \p stencil may equal \p result, but the range <tt>[stencil, stencil + (last - first))</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform_if using the \p thrust::host
* execution policy for parallelization:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
* #include <thrust/execution_policy.h>
* ...
*
* int data[10] = {-5, 0, 2, -3, 2, 4, 0, -1, 2, 8};
* int stencil[10] = { 1, 0, 1, 0, 1, 0, 1, 0, 1, 0};
*
* thrust::negate<int> op;
* thrust::identity<int> identity;
*
* thrust::transform_if(thrust::host, data, data + 10, stencil, data, op, identity); // in-place transformation
*
* // data is now {5, 0, -2, -3, -2, 4, 0, -1, -2, 8};
* \endcode
*
* \see thrust::transform
*/
template<typename DerivedPolicy,
typename InputIterator1,
typename InputIterator2,
typename ForwardIterator,
typename UnaryFunction,
typename Predicate>
ForwardIterator transform_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
InputIterator1 first, InputIterator1 last,
InputIterator2 stencil,
ForwardIterator result,
UnaryFunction op,
Predicate pred);
/*! This version of \p transform_if conditionally applies a unary function
* to each element of an input sequence and stores the result in the corresponding
* position in an output sequence if the corresponding position in a stencil sequence
* satisfies a predicate. Otherwise, the corresponding position in the
* output sequence is not modified.
*
* Specifically, for each iterator <tt>i</tt> in the range <tt>[first, last)</tt> the
* predicate <tt>pred(*s)</tt> is evaluated, where <tt>s</tt> is the corresponding input
* iterator in the range <tt>[stencil, stencil + (last - first) )</tt>. If this predicate
* evaluates to \c true, the result of <tt>op(*i)</tt> is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* <tt>[result, result + (last - first) )</tt>. Otherwise, <tt>op(*i)</tt> is
* not evaluated and no assignment occurs. The input and output sequences may coincide,
* resulting in an in-place transformation.
*
* \param first The beginning of the input sequence.
* \param last The end of the input sequence.
* \param stencil The beginning of the stencil sequence.
* \param result The beginning of the output sequence.
* \param op The tranformation operation.
* \param pred The predicate operation.
* \return The end of the output sequence.
*
* \tparam InputIterator1 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator1's \c value_type is convertible to \c UnaryFunction's \c argument_type.
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator2's \c value_type is convertible to \c Predicate's \c argument_type.
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>.
* \tparam UnaryFunction is a model of <a href="http://www.sgi.com/tech/stl/UnaryFunction.html">Unary Function</a>
* and \c UnaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
*
* \pre \p first may equal \p result, but the range <tt>[first, last)</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
* \pre \p stencil may equal \p result, but the range <tt>[stencil, stencil + (last - first))</tt> shall not overlap the range <tt>[result, result + (last - first))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform_if:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
*
* int data[10] = {-5, 0, 2, -3, 2, 4, 0, -1, 2, 8};
* int stencil[10] = { 1, 0, 1, 0, 1, 0, 1, 0, 1, 0};
*
* thrust::negate<int> op;
* thrust::identity<int> identity;
*
* thrust::transform_if(data, data + 10, stencil, data, op, identity); // in-place transformation
*
* // data is now {5, 0, -2, -3, -2, 4, 0, -1, -2, 8};
* \endcode
*
* \see thrust::transform
*/
template<typename InputIterator1,
typename InputIterator2,
typename ForwardIterator,
typename UnaryFunction,
typename Predicate>
ForwardIterator transform_if(InputIterator1 first, InputIterator1 last,
InputIterator2 stencil,
ForwardIterator result,
UnaryFunction op,
Predicate pred);
/*! This version of \p transform_if conditionally applies a binary function
* to each pair of elements from two input sequences and stores the result in the corresponding
* position in an output sequence if the corresponding position in a stencil sequence
* satifies a predicate. Otherwise, the corresponding position in the
* output sequence is not modified.
*
* Specifically, for each iterator <tt>i</tt> in the range <tt>[first1, last1)</tt> and
* <tt>j = first2 + (i - first1)</tt> in the range <tt>[first2, first2 + (last1 - first1) )</tt>,
* the predicate <tt>pred(*s)</tt> is evaluated, where <tt>s</tt> is the corresponding input
* iterator in the range <tt>[stencil, stencil + (last1 - first1) )</tt>. If this predicate
* evaluates to \c true, the result of <tt>binary_op(*i,*j)</tt> is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* <tt>[result, result + (last1 - first1) )</tt>. Otherwise, <tt>binary_op(*i,*j)</tt> is
* not evaluated and no assignment occurs. The input and output sequences may coincide,
* resulting in an in-place transformation.
*
* The algorithm's execution is parallelized as determined by \p exec.
*
* \param exec The execution policy to use for parallelization.
* \param first1 The beginning of the first input sequence.
* \param last1 The end of the first input sequence.
* \param first2 The beginning of the second input sequence.
* \param stencil The beginning of the stencil sequence.
* \param result The beginning of the output sequence.
* \param binary_op The transformation operation.
* \param pred The predicate operation.
* \return The end of the output sequence.
*
* \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>
* and \c InputIterator1's \c value_type is convertible to \c BinaryFunction's \c first_argument_type.
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator2's \c value_type is convertible to \c BinaryFunction's \c second_argument_type.
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>.
* \tparam BinaryFunction is a model of <a href="http://www.sgi.com/tech/stl/BinaryFunction.html">Binary Function</a>
* and \c BinaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
*
* \pre \p first1 may equal \p result, but the range <tt>[first1, last1)</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
* \pre \p first2 may equal \p result, but the range <tt>[first2, first2 + (last1 - first1))</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
* \pre \p stencil may equal \p result, but the range <tt>[stencil, stencil + (last1 - first1))</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform_if using the \p thrust::host
* execution policy for parallelization:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
* #include <thrust/execution_policy.h>
* ...
*
* int input1[6] = {-5, 0, 2, 3, 2, 4};
* int input2[6] = { 3, 6, -2, 1, 2, 3};
* int stencil[8] = { 1, 0, 1, 0, 1, 0};
* int output[6];
*
* thrust::plus<int> op;
* thrust::identity<int> identity;
*
* thrust::transform_if(thrust::host, input1, input1 + 6, input2, stencil, output, op, identity);
*
* // output is now {-2, 0, 0, 3, 4, 4};
* \endcode
*
* \see thrust::transform
*/
template<typename DerivedPolicy,
typename InputIterator1,
typename InputIterator2,
typename InputIterator3,
typename ForwardIterator,
typename BinaryFunction,
typename Predicate>
ForwardIterator transform_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec,
InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2,
InputIterator3 stencil,
ForwardIterator result,
BinaryFunction binary_op,
Predicate pred);
/*! This version of \p transform_if conditionally applies a binary function
* to each pair of elements from two input sequences and stores the result in the corresponding
* position in an output sequence if the corresponding position in a stencil sequence
* satifies a predicate. Otherwise, the corresponding position in the
* output sequence is not modified.
*
* Specifically, for each iterator <tt>i</tt> in the range <tt>[first1, last1)</tt> and
* <tt>j = first2 + (i - first1)</tt> in the range <tt>[first2, first2 + (last1 - first1) )</tt>,
* the predicate <tt>pred(*s)</tt> is evaluated, where <tt>s</tt> is the corresponding input
* iterator in the range <tt>[stencil, stencil + (last1 - first1) )</tt>. If this predicate
* evaluates to \c true, the result of <tt>binary_op(*i,*j)</tt> is assigned to <tt>*o</tt>,
* where <tt>o</tt> is the corresponding output iterator in the range
* <tt>[result, result + (last1 - first1) )</tt>. Otherwise, <tt>binary_op(*i,*j)</tt> is
* not evaluated and no assignment occurs. The input and output sequences may coincide,
* resulting in an in-place transformation.
*
* \param first1 The beginning of the first input sequence.
* \param last1 The end of the first input sequence.
* \param first2 The beginning of the second input sequence.
* \param stencil The beginning of the stencil sequence.
* \param result The beginning of the output sequence.
* \param binary_op The transformation operation.
* \param pred The predicate operation.
* \return The end of the output sequence.
*
* \tparam InputIterator1 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator1's \c value_type is convertible to \c BinaryFunction's \c first_argument_type.
* \tparam InputIterator2 is a model of <a href="http://www.sgi.com/tech/stl/InputIterator.html">Input Iterator</a>
* and \c InputIterator2's \c value_type is convertible to \c BinaryFunction's \c second_argument_type.
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>.
* \tparam BinaryFunction is a model of <a href="http://www.sgi.com/tech/stl/BinaryFunction.html">Binary Function</a>
* and \c BinaryFunction's \c result_type is convertible to \c OutputIterator's \c value_type.
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>.
*
* \pre \p first1 may equal \p result, but the range <tt>[first1, last1)</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
* \pre \p first2 may equal \p result, but the range <tt>[first2, first2 + (last1 - first1))</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
* \pre \p stencil may equal \p result, but the range <tt>[stencil, stencil + (last1 - first1))</tt> shall not overlap the range <tt>[result, result + (last1 - first1))</tt> otherwise.
*
* The following code snippet demonstrates how to use \p transform_if:
*
* \code
* #include <thrust/transform.h>
* #include <thrust/functional.h>
*
* int input1[6] = {-5, 0, 2, 3, 2, 4};
* int input2[6] = { 3, 6, -2, 1, 2, 3};
* int stencil[8] = { 1, 0, 1, 0, 1, 0};
* int output[6];
*
* thrust::plus<int> op;
* thrust::identity<int> identity;
*
* thrust::transform_if(input1, input1 + 6, input2, stencil, output, op, identity);
*
* // output is now {-2, 0, 0, 3, 4, 4};
* \endcode
*
* \see thrust::transform
*/
template<typename InputIterator1,
typename InputIterator2,
typename InputIterator3,
typename ForwardIterator,
typename BinaryFunction,
typename Predicate>
ForwardIterator transform_if(InputIterator1 first1, InputIterator1 last1,
InputIterator2 first2,
InputIterator3 stencil,
ForwardIterator result,
BinaryFunction binary_op,
Predicate pred);
/*! \} // end transformations
*/
} // end namespace thrust
#include <thrust/detail/transform.inl>