parallel_transform Function

  • Article

Applies a specified function object to each element in a source range, or to a pair of elements from two source ranges, and copies the return values of the function object into a destination range, in parallel. This functional is semantically equivalent to std::transform.

template <
   typename _Input_iterator1,
   typename _Output_iterator,
   typename _Unary_operator
>
_Output_iterator parallel_transform(
   _Input_iterator1_First1,
   _Input_iterator1_Last1,
   _Output_iterator_Result,
   const _Unary_operator& _Unary_op,
   const auto_partitioner& _Part = auto_partitioner()
);

template <
   typename _Input_iterator1,
   typename _Output_iterator,
   typename _Unary_operator
>
_Output_iterator parallel_transform(
   _Input_iterator1_First1,
   _Input_iterator1_Last1,
   _Output_iterator_Result,
   const _Unary_operator& _Unary_op,
   const static_partitioner& _Part
);

template <
   typename _Input_iterator1,
   typename _Output_iterator,
   typename _Unary_operator
>
_Output_iterator parallel_transform(
   _Input_iterator1_First1,
   _Input_iterator1_Last1,
   _Output_iterator_Result,
   const _Unary_operator& _Unary_op,
   const simple_partitioner& _Part
);

template <
   typename _Input_iterator1,
   typename _Output_iterator,
   typename _Unary_operator
>
_Output_iterator parallel_transform(
   _Input_iterator1_First1,
   _Input_iterator1_Last1,
   _Output_iterator_Result,
   const _Unary_operator& _Unary_op,
   affinity_partitioner& _Part
);

template <
   typename _Input_iterator1,
   typename _Input_iterator2,
   typename _Output_iterator,
   typename _Binary_operator,
   typename _Partitioner
>
_Output_iterator parallel_transform(
   _Input_iterator1_First1,
   _Input_iterator1_Last1,
   _Input_iterator2_First2,
   _Output_iterator_Result,
   const _Binary_operator& _Binary_op,
   _Partitioner&& _Part
);

template <
   typename _Input_iterator1,
   typename _Input_iterator2,
   typename _Output_iterator,
   typename _Binary_operator
>
_Output_iterator parallel_transform(
   _Input_iterator1_First1,
   _Input_iterator1_Last1,
   _Input_iterator2_First2,
   _Output_iterator_Result,
   const _Binary_operator& _Binary_op
);

Parameters

  • _Input_iterator1
    The type of the first or only input iterator.

  • _Output_iterator
    The type of the output iterator.

  • _Unary_operator
    The type of the unary functor to be executed on each element in the input range.

  • _Input_iterator2
    The type of second input iterator.

  • _Binary_operator
    The type of the binary functor executed pairwise on elements from the two source ranges.

  • _Partitioner

  • _First1
    An input iterator addressing the position of the first element in the first or only source range to be operated on.

  • _Last1
    An input iterator addressing the position one past the final element in the first or only source range to be operated on.

  • _Result
    An output iterator addressing the position of the first element in the destination range.

  • _Unary_op
    A user-defined unary function object that is applied to each element in the source range.

  • _Part
    A reference to the partitioner object. The argument can be one of constauto_partitioner&, conststatic_partitioner&, constsimple_partitioner& or affinity_partitioner& If an affinity_partitioner object is used, the reference must be a non-const l-value reference, so that the algorithm can store state for future loops to re-use.

  • _First2
    An input iterator addressing the position of the first element in the second source range to be operated on.

  • _Binary_op
    A user-defined binary function object that is applied pairwise, in a forward order, to the two source ranges.

Return Value

An output iterator addressing the position one past the final element in the destination range that is receiving the output elements transformed by the function object.

Remarks

auto_partitioner will be used for the overloads without an explicit partitioner argument.

For iterators that do not support random access, only auto_partitioner is supported.

The overloads that take the argument _Unary_op transform the input range into the output range by applying the unary functor to each element in the input range. _Unary_op must support the function call operator with signature operator()(T) where T is the value type of the range being iterated over.

The overloads that take the argument _Binary_op transform two input ranges into the output range by applying the binary functor to one element from the first input range and one element from the second input range. _Binary_op must support the function call operator with signature operator()(T, U) where T, U are value types of the two input iterators.

For more information, see Parallel Algorithms.

Requirements

Header: ppl.h

Namespace: concurrency

See Also

Reference

concurrency Namespace