[R] Sprintf to call data frame from environment

Jim Lemon drjimlemon at gmail.com
Wed May 25 00:39:17 CEST 2016

Hi Beatriz,
I'll guess that you have a number of files with names like this:


Each one can be read with a function like read.table and will return a
data frame with default names (V1, V2, ...). You then want to extract
the first element (column) of the data frame. If I'm correct, try

# nfiles is the number of files you want to read
for(i in 1:nfiles) {
 # you will probably have to add the appropriate arguments to read.table

The list V1s should contain the first columns of all the data frames read.


On Wed, May 25, 2016 at 7:01 AM, 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!
>         sprintf("Samples_%s.txt", 1)$V1
> Note: I need to do it in this way because I have the code into a for loop.
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