chunked-class: Chunked Vectors, Arrays, and Lists

In kuwisdelu/matter: Scientific computing for out-of-memory signals and images

Chunked Vectors, Arrays, and Lists

Description

The chunked class implements chunked wrappers for vectors, arrays, and lists for parallel iteration.

Usage

## Instance creation
chunked_vec(x, nchunks = NA,
    depends = NULL, drop= FALSE)

chunked_mat(x, margin, nchunks = NA,
    depends = NULL, drop= FALSE)

chunked_list(..., nchunks = NA,
    depends = NULL, drop= FALSE)

## Additional methods documented below

Arguments

x, ...	The data to be chunked. If multiple objects are passed via ..., then they are all recycled to the same length.
nchunks	The number of chunks to use. If NA (the default), this is taken from getOption("matter.default.nchunks"). For IO-bound operations, using fewer chunks will often be faster, but use more memory.
margin	Which array margin should be chunked.
depends	A list with length equal to the extent of X. Each element of depends should give a vector of indices which correspond to other elements of X on which each computation depends. These elements are passed to FUN. For time efficiency, no attempt is made to verify these indices are valid.
drop	The value passed to drop when subsetting the chunks.

Value

An object derived from class chunked.

Slots

data:

The data.

index:

The chunk indices.

drop:

The value passed to drop when subsetting the chunks.

margin:

The array margin for the chunks.

Creating Objects

chunked_vec, chunked_mat and chunked_list instances can be created through chunked_vec(), chunked_mat(), and chunked_list(), respectively.

Methods

Standard generic methods:

length(x):

Get number of chunks.

lengths(x):

Get chunk sizes for each chunk.

x[i, ...]:

Get chunks.

x[[i]]:

Get a single chunk.

Author(s)

Kylie A. Bemis

See Also

chunkApply

Examples

x <- matrix(runif(200), nrow=10, ncol=20)

y <- chunked_mat(x, margin=2, nchunks=5)
print(y)

kuwisdelu/matter documentation built on July 16, 2024, 1:28 p.m.