Template Function thrust::exclusive_scan(InputIterator, InputIterator, OutputIterator, T)¶
Function Documentation¶
-
template<typename
InputIterator
, typenameOutputIterator
, typenameT
>
OutputIteratorthrust
::
exclusive_scan
(InputIterator first, InputIterator last, OutputIterator result, T init) exclusive_scan
computes an exclusive prefix sum operation. The term ‘exclusive’ means that each result does not include the corresponding input operand in the partial sum. More precisely,init
is assigned to*result
and the sum ofinit
and*first
is assigned to*(result + 1)
, and so on. This version ofexclusive_scan
assumes plus as the associative operator but requires an initial valueinit
. When the input and output sequences are the same, the scan is performed in-place.The following code snippet demonstrates how to use
exclusive_scan
- Return
The end of the output sequence.
- Pre
first
may equalresult
but the range[first, last)
and the range[result, result + (last - first))
shall not overlap otherwise.- Parameters
first
: The beginning of the input sequence.last
: The end of the input sequence.result
: The beginning of the output sequence.init
: The initial value.
- Template Parameters
InputIterator
: is a model of Input Iterator andInputIterator's
value_type
is convertible toOutputIterator's
value_type
.OutputIterator
: is a model of Output Iterator, and ifx
andy
are objects ofOutputIterator's
value_type
, thenx + y
is defined.T
: is convertible toOutputIterator's
value_type
.
#include <thrust/scan.h> int data[6] = {1, 0, 2, 2, 1, 3}; thrust::exclusive_scan(data, data + 6, data, 4); // in-place scan // data is now {4, 5, 5, 7, 9, 10}