dim {base}R Documentation

Dimensions of an Object

Description

Retrieve or set the dimension of an object.

Usage

dim(x)
dim(x) <- value

Arguments

x an R object, for example a matrix, array or data frame.
value For the default method, either NULL or a numeric vector which coerced to integer (by truncation).

Details

The functions dim and dim<- are generic.

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”).

Value

For an array (and hence in particular, for a matrix) dim retrieves the dim attribute of the object. It is NULL or a vector of mode integer.

References

Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.

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]

[Package base version 2.1.0 Index]