expandAsMatrix: expandAsMatrix

In edgeR: Empirical Analysis of Digital Gene Expression Data in R

Description

Expand scalar or vector to a matrix.

Usage

expandAsMatrix(x, dim=NULL, byrow=TRUE)

Arguments

x	scalar, vector, matrix or CompressedMatrix.
dim	integer vector of length 2 specifying the required dimensions of the output matrix.
byrow	logical scalar specifying if matrix should be filled by columns or rows for a vector x.

Details

This function expands a scalar, row/column vector or CompressedMatrix to be a matrix of dimensions dim. It is used internally in edgeR to convert offsets, weights and other values to a matrix for consistent handling. If dim is NULL, the function is equivalent to calling as.matrix(x).

If x is a vector, its length must match one of the output dimensions. The matrix will then be filled by repeating the matrix across the matching dimension. For example, if length(x)==dim[1], the matrix will be filled such that each row contains x. If both dimensions match, filling is determined by byrow, with filling by rows as the default.

If x CompressedMatrix object, the size of any non-repeated dimensions must be consistent with corresponding output dimension. The byrow argument will be ignored as the repeat specifications will dictate how expansion should be performed. See ?CompressedMatrix for more details.

Value

Numeric matrix of dimension dim.

Author(s)

Gordon Smyth

Examples

expandAsMatrix(1:3,c(4,3))
expandAsMatrix(1:4,c(4,3))

Example output

Loading required package: limma
     [,1] [,2] [,3]
[1,]    1    2    3
[2,]    1    2    3
[3,]    1    2    3
[4,]    1    2    3
     [,1] [,2] [,3]
[1,]    1    1    1
[2,]    2    2    2
[3,]    3    3    3
[4,]    4    4    4

edgeR documentation built on Jan. 16, 2021, 2:03 a.m.