assign(x, value, pos = -1, envir = sys.frame(sys.parent()),
inherits = FALSE, immediate = TRUE)
x <- value
x <<- value
value -> x
value ->> x
x
| a variable name (given as a quoted string). |
value
|
a value to be assigned to x.
|
pos
|
an index into the search list which determines which
environment the assignment is to take place in. A character string may
also be used. The environment
can also be specified directly with envir.
|
envir
|
the environment in which to assign. The
default is the environment where the call to assign takes place.
|
inherits
| should the enclosing frames of the environment be inspected? |
immediate
| an ignored compatibility feature. |
value to the variable x. If no envir is
specified, then the assignment takes place in the currently active
environment.
If inherits is TRUE, parents 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 global environment.
If inherits is FALSE, assignment takes place in the
initial frame of envir.
The arrow forms of assignment provide shortcut ways to carry out
assignment. The <- and -> forms carry out assignment
in the local environment frame, while the <<- and ->>
forms cause a search to made through the environment for an existing
definition of the variable being assigned. If such a variable is
found then its value is redefined, otherwise assignment takes place
globally.
Note that the action of <<- and ->> differs from
that in the S language, but is useful in conjunction with the
scoping rules of R.
get, 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