futile.matrix (version 1.2.2)

futile.matrix-package: A collection of matrix manipulation functions

Description

This is a sub package of the futile collection of R libraries. It provides various convenience functions for examining data within matrices as well as some optimized functions for reading matrices in various formats.

Details

Package:

futile.matrix

Type:

Package

Version:

1.2.2

Date:

2014-05-06

License:

LGPL-3

LazyLoad:

yes

Matrices are a widely used data type in R, which provides many fine language features and built-in functions for working with them. As matrices grow in size, they become harder to work with, not from a language perspective, but from an introspection perspective. Using the subsetting functions is typically the approach used to extract subsets of data from a matrix, but complex constructions leave code unreadable as well as fragile. The futile.matrix package addresses this issue by providing subsetting functions to access data in a readable way that is (hopefully) consistent with R idioms. It also provides functions for growing matrices in defined ways.

While R is strong in manipulating matrices, getting matrices into R can at times be a challenge. Large (but not huge) matrices can be slow to load, so futile.matrix provides some functions that speed up the reading process. The implementation provides routines for reading both dense matrices and sparse matrices (in CSR, CSC, and triplet forms). Note that this does not attempt to replace packages like bigmemory, which deals with matrices orders of magnitude larger.

See Also

select, expand, read.matrix

Examples

library(datasets)
select(swiss, "Rive")
select(swiss, col.pat='^E')
select(swiss, "Rive", '^E') <- -1

dimnames <- list( c(rownames(swiss), 'Zermat', 'Zurich', 'Geneva'),
  c(colnames(swiss), 'Age','Hair.Color') )
my.swiss <- expand(swiss, dimnames)