Template Function thrust::partition_copy(InputIterator1, InputIterator1, InputIterator2, OutputIterator1, OutputIterator2, Predicate)¶
Function Documentation¶
-
template<typename
InputIterator1
, typenameInputIterator2
, typenameOutputIterator1
, typenameOutputIterator2
, typenamePredicate
>
thrust::pair<OutputIterator1, OutputIterator2>thrust
::
partition_copy
(InputIterator1 first, InputIterator1 last, InputIterator2 stencil, OutputIterator1 out_true, OutputIterator2 out_false, Predicate pred) partition_copy
differs from partition only in that the reordered sequence is written to difference output sequences, rather than in place.partition_copy
copies the elements[first, last)
based on the function objectpred
which is applied to a range of stencil elements. All of the elements whose corresponding stencil element satisfiespred
are copied to the range beginning atout_true
and all the elements whose stencil element fails to satisfy it are copied to the range beginning atout_false
.The following code snippet demonstrates how to use
partition_copy
to separate a sequence into two output sequences of even and odd numbers.- Return
A
pair
p such thatp.first
is the end of the output range beginning atout_true
andp.second
is the end of the output range beginning atout_false
.- Pre
The input ranges shall not overlap with either output range.
- Parameters
first
: The beginning of the sequence to reorder.last
: The end of the sequence to reorder.stencil
: The beginning of the stencil sequence.out_true
: The destination of the resulting sequence of elements which satisfypred
.out_false
: The destination of the resulting sequence of elements which fail to satisfypred
.pred
: A function object which decides to which partition each element of the sequence[first, last)
belongs.
- Template Parameters
InputIterator1
: is a model of Input Iterator, andInputIterator's
value_type
is convertible toOutputIterator1
andOutputIterator2's
value_types
.InputIterator2
: is a model of Input Iterator, andInputIterator2's
value_type
is convertible toPredicate's
argument_type
.OutputIterator1
: is a model of Output Iterator.OutputIterator2
: is a model of Output Iterator.Predicate
: is a model of Predicate.
#include <thrust/partition.h> #include <thrust/functional.h> ... int A[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; int S[] = {0, 1, 0, 1, 0, 1, 0, 1, 0, 1}; int result[10]; const int N = sizeof(A)/sizeof(int); int *evens = result; int *odds = result + 5; thrust::stable_partition_copy(A, A + N, S, evens, odds, thrust::identity<int>()); // A remains {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} // S remains {0, 1, 0, 1, 0, 1, 0, 1, 0, 1} // result is now {2, 4, 6, 8, 10, 1, 3, 5, 7, 9} // evens points to {2, 4, 6, 8, 10} // odds points to {1, 3, 5, 7, 9}
- Note
The relative order of elements in the two reordered sequences is not necessarily the same as it was in the original sequence. A different algorithm, stable_partition_copy, does guarantee to preserve the relative order.
- See
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2569.pdf
- See
stable_partition_copy
- See
partition