| dim {base} | R Documentation |
Retrieve or set the dimension of an object.
dim(x) dim(x) <- value
x |
an R object, for example a matrix, array or data frame. |
value |
For the default method, either NULL or
a numeric vector, which is coerced to integer (by truncation). |
The functions dim and dim<- are generic.
dim has a method for data.frames, which returns
the lengths of the row.names attribute of x and
of x (as the numbers of rows and columns respectitvely).
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.
The replacement method changes the "dim" attribute (provided the
new value is compatible) and removes any "dimnames" and
"names" attributes.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
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]