logical {base} | R Documentation |
Create or test for objects of type "logical"
, and the basic
logical ``constants''.
TRUE FALSE T; F logical(length = 0) as.logical(x, ...) is.logical(x)
length |
desired length. |
x |
object to be coerced or tested. |
... |
further arguments passed to or from other methods. |
TRUE
and FALSE
are part of the R language, where
T
and F
are global variables set to these.
All four are logical(1)
vectors.
is.logical
is generic: you can write methods to handle
of specific classes of objects, see InternalMethods.
logical
creates a logical vector of the specified length.
Each element of the vector is equal to FALSE
.
as.logical
attempts to coerce its argument to be of logical
type. For factor
s, this uses the levels
(labels) and not the codes
.
is.logical
returns TRUE
or FALSE
depending on
whether its argument is of logical type or not.