Safe Haskell	Safe-Infered

Data.Array.Parallel.Unlifted.Sequential.USegd

Contents

Types
Constructors
Projections
Operations

Description

Segment Descriptors.

See Data.Array.Parallel.Unlifted for how this works.

Synopsis

Types

data USegd Source

Segment descriptor.

Constructors

USegd
Fields usegd_lengths :: !(Vector Int) Length of each segment. usegd_indices :: !(Vector Int) Starting index of each segment. usegd_elements :: !Int Total number of elements in the flat array.

Instances

Eq USegd
Show USegd
PprPhysical USegd

Constructors

mkUSegd Source

Arguments

:: Vector Int	Length of each segment.
-> Vector Int	Starting index of each segment.
-> Int	Total number of elements in the flat array.
-> USegd

O(1). Construct a new segment descriptor.

valid :: USegd -> Bool Source

O(1). Check the internal consistency of a segment descriptor.

As the indices and elemens field can be generated based on the segment lengths, we check the consistency by rebuilding these fields and comparing the rebuilt ones against the originals.

empty :: USegd Source

O(1). Construct an empty segment descriptor, with no elements or segments.

singleton :: Int -> USegd Source

O(1). Construct a singleton segment descriptor. The single segment covers the given number of elements.

fromLengths :: Vector Int -> USegd Source

O(segs). Convert an array of segment lengths into a segment descriptor.

The array contains the length of each segment, and we compute the indices from that.

Projections

length :: USegd -> Int Source

O(1). Yield the overall number of segments.

takeLengths :: USegd -> Vector Int Source

O(1). Yield the lengths of the individual segments.

takeIndices :: USegd -> Vector Int Source

O(1). Yield the segment indices of a segment descriptor.

takeElements :: USegd -> Int Source

O(1). Yield the number of data elements.

getSeg :: USegd -> Int -> (Int, Int)Source

O(1). Get the length and segment index of a segment

Operations

append :: USegd -> USegd -> USegd Source

O(segs). Produce a segment descriptor that describes the result of appending two arrays.

slice Source

Arguments

:: USegd	Source segment descriptor.
-> Int	Index of first segment.
-> Int	Number of segments to slice out.
-> USegd

O(segs) Extract a slice of a segment descriptor, avoiding copying where possible.

We can share the segment lengths with the original segment descriptor, but still need to recompute the starting indices of each. Hence runtime is O(segs) in the number of segments sliced out.

extract Source

Arguments

:: USegd	Source segment desciptor.
-> Int	Undex of the first segment.
-> Int	Number of segments to extract out.
-> USegd

Extract a slice of a segment descriptor, copying everything.

In contrast to slice, this function copies the array of segment lengths as well as recomputing the starting indices of each.