[R] call object from character?

[Greg Snow]

Almost always when people ask this question (it and its answer are FAQ
7.21) it is because they want to do things the wrong way (just don't
know there is a better way).

The better way is to put the variables that you want to access in this
way into a list, then you can easily access the objects in the list by
name (or position, or all of them, etc.):

mylist <- list(a=12)
call_A <- 'a'
mylist[[call_A]]

Adding more objects to the list is easier than creating new data
objects in the global environment, and if you want to do something
with all those objects (copy, delete, rename, etc.) then you have 1
list to work with rather than a bunch of separate objects.  If you
want to do the same operation on all the objects (the common follow-up
question) then if they are in a list you can use lapply, sapply, or
vapply and it is much simpler than looping and getting.

On Wed, Apr 18, 2012 at 8:25 PM, chuck.01 <CharlieTheBrown77 at gmail.com> wrote:
> Let say I have an object (I hope my terminology is correct) a
> a <- 12
>> a
> [1] 12
>
> And "a" has been assigned the number 12, or whatever
> And lets say I have a character "call_A"
> call_A <- "a"
>>call_A
> [1] "a"
>
> What is the function "F" that allows this to happen:
>> F( call_A )
> [1] 12
>
>
> --
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> Sent from the R help mailing list archive at Nabble.com.
>
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-- 
Gregory (Greg) L. Snow Ph.D.
538280 at gmail.com