[mdlug] simple stats from piping numbers into R?

[Robert Citek]

On Tue, Apr 20, 2010 at 8:39 AM, Jonathan Billings <billings at negate.org> wrote:
> On Thu, Apr 15, 2010 at 05:33:35PM -0400, Robert Citek wrote:
>> That works, but I'd prefer to pipe the data in rather than go through
>> the intermediary of a file or a named pipe.
>
> I believe you can refer to "stdin" (I've also seen /dev/stdin) as the
> file in scan:
>
> % cat test.r
> #!/usr/bin/Rscript
>
> num <- scan("stdin",quiet=TRUE)
> summary(num)
>
> % seq 1 100 | ./test.r
>   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
>   1.00   25.75   50.50   50.50   75.25  100.00

Perfect!  Rscript with -e and "stdin" were the trick.   Here's exactly
what I wanted to do:

$ seq 1 1000000 |\
time -p Rscript -e 'summary(read.csv("stdin", head=FALSE))'

       V1
 Min.   :      1
 1st Qu.: 250001
 Median : 500000
 Mean   : 500000
 3rd Qu.: 750000
 Max.   :1000000
real 11.07
user 10.55
sys 0.20

Thanks for all the replies.

Regards,
- Robert