attr {base} | R Documentation |
Get or set specific attributes of an object.
attr(x, which) attr(x, which) <- value
x |
an object whose attributes are to be accessed. |
which |
a character string specifying which attribute is to be accessed. |
value |
an object, the new value of the attribute. |
These functions provide access to a single attribute of an object. The
first form returns the value of the named attribute. The
replacement form causes the named attribute to take the value specified.
The first form first looks for an exact match to which
amongst the
attributes of x
, then a partial match. If no exact match is
found and more than one partial match is found, the result is NULL
.
Note that some attributes (namely class
, comment
,
dim
, dimnames
, names
and tsp
) are treated specially and have restrictions on the
values which can be set.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
# create a 2 by 5 matrix x <- 1:10 attr(x,"dim") <- c(2, 5)