dimnames {base} | R Documentation |
Retrieve or set the dimnames of an object.
dimnames(x) dimnames(x) <- value
x |
an R object, for example a matrix, array or data frame. |
value |
a possible value for dimnames(x) : see
“Value”. |
The functions dimnames
and dimnames<-
are generic.
For an array
(and hence in particular, for a
matrix
), they retrieve or set the dimnames
attribute (see attributes) of the object. A list
value
can have names, and these will be used to label the
dimensions of the array where appropriate.
For an array/matrix, vector and factor components of value
will
be coerced to character, but no other coercions are done.
Both have methods for data frames. The dimnames of a data frame are
its row.names
and its names
. For the
replacement method each component of value
will be coerced by
as.character
.
The dimnames of a matrix or array can be NULL
or a list of the
same length as dim(x)
. If a list, its components are either
NULL
or a character vector the length of the appropriate
dimension of x
.
For the "data.frame"
method both dimnames must be non-null, and
the rownames must be contain no duplicates nor missing values.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
rownames
, colnames
;
array
, matrix
, data.frame
.
## simple versions of rownames and colnames ## could be defined as follows rownames0 <- function(x) dimnames(x)[[1]] colnames0 <- function(x) dimnames(x)[[2]]