Functional Definition of

Collaboration diagram for Functional Definition of:

Functions
template<typename Tag = tags::binomial, typename Op >
result_of::scan< tags::scan< Tag, tags::inclusive >, Op >	stapl::skeletons::scan (Op &&op)
	A scan skeleton which is specialized based on the tag given.
template<typename Tag = tags::blelloch, typename Op , typename T >
result_of::scan< tags::scan< Tag, tags::exclusive >, Op >	stapl::skeletons::scan (Op &&op, T const &initial_value)
	In an exclusive scan each element in the result is the result of the cumulative operation on all elements before it. More...
template<typename ValueType , typename Tag = tags::binomial, typename Op >
result_of::scan_reduce< ValueType, Tag, tags::inclusive, Op >	stapl::skeletons::scan_reduce (Op &&op)
	This skeleton combines the functionality of inclusive_scan skeleton and reduce_to_locs skeletons. More...
template<typename ValueType , typename Tag = tags::blelloch, typename Op >
result_of::scan_reduce< ValueType, Tag, tags::exclusive, Op >	stapl::skeletons::scan_reduce (Op &&op, ValueType const &initial_value)
	This skeleton combines the functionality of exclusive_scan skeleton and reduce_to_locs skeletons. More...

Detailed Description

Algorithms as Skeletons

Function Documentation

scan()

template<typename Tag = tags::blelloch, typename Op , typename T >

result_of::scan<tags::scan<Tag, tags::exclusive>, Op> stapl::skeletons::scan	(	Op &&	op,
		T const &	initial_value
	)

In an exclusive scan each element in the result is the result of the cumulative operation on all elements before it.

For example, if + is used as the operation, each element in the output is the sum of all elements before it, and the first element is the neutral value. An exclusive scan of [1, 2, 3, 4, ...] would be [0, 1, 3, 6, 10, ...].

Parameters

op	the operation to be used to compute the scan results
initial_value	the value for the first element of the output

Template Parameters

Tag	the type of exclusive scan to be used

Returns

an exclusive scan specified by the Tag

See also

exclusive_scan

scan_reduce() [1/2]

template<typename ValueType , typename Tag = tags::binomial, typename Op >

result_of::scan_reduce<ValueType, Tag, tags::inclusive, Op> stapl::skeletons::scan_reduce

(

Op &&

op

)

This skeleton combines the functionality of inclusive_scan skeleton and reduce_to_locs skeletons.

This skeleton is useful in cases when we both need the result of scan over the inputs and the reduction of input values. It avoids doing an extra iteration over the data.

Parameters

op	the operation to be used to compute the scan results

Template Parameters

Tag	the type of exclusive scan to be used

Returns

an exclusive scan specified by the Tag

See also

inclusive_scan

scan

reduce_to_locs

scan_reduce() [2/2]

template<typename ValueType , typename Tag = tags::blelloch, typename Op >

result_of::scan_reduce<ValueType, Tag, tags::exclusive, Op> stapl::skeletons::scan_reduce	(	Op &&	op,
		ValueType const &	initial_value
	)

This skeleton combines the functionality of exclusive_scan skeleton and reduce_to_locs skeletons.

This skeleton is useful in cases when we both need the result of scan over the inputs and the reduction of input values. It avoids doing an extra iteration over the data.

Parameters

op	the operation to be used to compute the scan results
initial_value	the value for the first element of the output

Template Parameters

Tag	the type of exclusive scan to be used

Returns

an exclusive scan specified by the Tag

See also

exclusive_scan

scan

reduce_to_locs