| vector {base} | R Documentation |
vector produces a vector of the given length and mode.
as.vector, a generic, attempts to coerce its argument into a
vector of mode mode (the default is to coerce to whichever mode
is most convenient).
is.vector returns TRUE if x is a vector (of mode
logical, integer, real, complex, character, raw or list if not
specified) or expression and FALSE otherwise.
vector(mode = "logical", length = 0) as.vector(x, mode = "any") is.vector(x, mode = "any")
mode |
A character string giving an atomic mode or "list",
or (not for vector) "any". |
length |
A non-negative integer specifying the desired length. |
x |
An object. |
The atomic modes are "logical", "integer", "numeric",
"complex", "character" and "raw".
is.vector returns FALSE if x has any attributes
except names. (This is incompatible with S.) On the other hand,
as.vector removes all attributes including names for
results of atomic mode.
Note that factors are not vectors; is.vector returns
FALSE and as.vector converts to a character vector for
mode = "any".
For vector, a vector of the given length and mode. Logical
vector elements are initialized to FALSE, numeric vector
elements to 0, character vector elements to "", raw
vector elements to nul bytes and list elements to NULL.
All attributes are removed from the answer if it is of an atomic mode.
as.vector and is.vector are quite distinct from the
meaning of the formal class "vector" in the methods
package, and hence as(x, "vector") and
is(x, "vector").
modes of "symbol", "pairlist" and
"expression" are allowed but have long been undocumented.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
c, is.numeric, is.list, etc.
df <- data.frame(x=1:3, y=5:7) ## Not run: ## Error: as.vector(data.frame(x=1:3, y=5:7), mode="numeric") ## End(Not run) x <- c(a = 1, b = 2) is.vector(x) as.vector(x) all.equal(x, as.vector(x)) ## FALSE ###-- All the following are TRUE: is.list(df) ! is.vector(df) ! is.vector(df, mode="list") is.vector(list(), mode="list") is.vector(NULL, mode="NULL")