[R] Sprintf to call data frame from environment

David Winsemius dwinsemius at comcast.net
Tue May 24 23:39:37 CEST 2016

> On May 24, 2016, at 2:01 PM, Beatriz <aguitatierra at hotmail.com> wrote:
> In my environment I have a data frame called Samples_1.txt.
> From this data frame I need to get variable V1.  My code doesn't work. Thanks!
> 	$V1
> Note: I need to do it in this way because I have the code into a for loop.

You are treating this as if R were a macro processor, which it's not. The only function that lets you pull in a data-object from the store of named objects using a character vector is `get`, so perhaps:

get( sprintf("Samples_%s.txt", 1) )$V1

And if you were considering the next step of hoping to pass a computed item to `$`, then forget that as well, and learn to use `[`.


David Winsemius
Alameda, CA, USA

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