| assign {base} | R Documentation |
Assign a value to a name in an environment.
assign(x, value, pos = -1, envir = as.environment(pos),
inherits = FALSE, immediate = TRUE)
x |
a variable name (given as a quoted string in the function call). |
value |
a value to be assigned to x. |
pos |
where to do the assignment. By default, assigns into the current environment. See the details for other possibilities. |
envir |
the environment to use. See the details section. |
inherits |
should the enclosing frames of the environment be inspected? |
immediate |
an ignored compatibility feature. |
The pos argument can specify the environment in which to assign
the object in any of several ways:
as an integer (the position in the search list); as
the character string name of an element in the search list; or as an
environment (including using sys.frame to
access the currently active function calls).
The envir argument is an alternative way to specify an
environment, but is primarily there for back compatibility.
assign does not dispatch assignment methods, so it cannot be
used to set elements of vectors, names, attributes, etc.
Note that assignment to an attached list or data frame changes the
attached copy and not the original object: see attach.
This function is invoked for its side effect, which is assigning
value to the variable x. If no envir is
specified, then the assignment takes place in the currently active
environment.
If inherits is TRUE, enclosing environments of the supplied
environment are searched until the variable x is encountered.
The value is then assigned in the environment in which the variable is
encountered. If the symbol is not encountered then assignment takes
place in the user's workspace (the global environment).
If inherits is FALSE, assignment takes place in the
initial frame of envir.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
<-,
get,
exists,
environment.
for(i in 1:6) { #-- Create objects 'r1', 'r2', ... 'r6' --
nam <- paste("r",i, sep=".")
assign(nam, 1:i)
}
ls(pat="^r..$")
##-- Global assignment within a function:
myf <- function(x) {
innerf <- function(x) assign("Global.res", x^2, env = .GlobalEnv)
innerf(x+1)
}
myf(3)
Global.res # 16
a <- 1:4
assign("a[1]", 2)
a[1] == 2 #FALSE
get("a[1]") == 2 #TRUE