indexByRow: Translates matrix indices by rows into indices by columns

In matrixStats: Methods that apply to rows and columns of a matrix

Description

Translates matrix indices by rows into indices by columns.

Usage

 ## S3 method for class 'matrix'
indexByRow(x, idxs=NULL, ...)

Arguments

x	A matrix.
idxs	A vector of indices. If NULL, all indices are returned.
...	Not use.

Value

Returns an integer vector of indices.

Author(s)

Henrik Bengtsson

Examples

 x <- matrix(NA, nrow=5, ncol=4)
 y <- t(x)
 idxs <- seq(along=x)

 # Assign by columns
 x[idxs] <- idxs
 print(x)

 # Assign by rows
 y[indexByRow(y, idxs)] <- idxs
 print(y)

 stopifnot(x == t(y))

matrixStats documentation built on May 2, 2019, 4:52 p.m.