Dimensions of an Object

Description

Retrieve or set the dimension of an object.

Usage

dim(x)
dim(x) <- values

Details

The functions dim and dim<- are generic.

For an array (and hence in particular, for a matrix) they retrieve or set the dim attribute of the object.

dim has a method for data frames, which returns the length of the row.names attribute of x and the length of x (the numbers of ``rows'' and ``columns'').

See Also

ncol, nrow and dimnames.

Examples

x <- 1:12 ; dim(x) <- c(3,4)
x

# simple versions of nrow and ncol could be defined as follows
nrow0 <- function(x) dim(x)[1]
ncol0 <- function(x) dim(x)[2]