[R] Any concept of 'by reference' or 'address of' in R?

[Don MacQueen]

I wouldn't assume R is making a copy; it depends on what you're doing 
with the dataframe.

I'd suggest using Rprof to find out where the cpu time is being 
spent. If you can adapt your problem to use all numbers or all 
characters then you can store the data in a matrix instead of a data 
frame, and potentially speed things up. (That advice is based on my 
own experience from a fairly large number of years ago, so it's 
possible that developments in R since then could negate the advice.)

-Don

At 4:38 PM -0700 9/18/09, Mark Knecht wrote:
>Hi,
>    Is there a way to pass the address of a data.frame through a set of
>functions in R? I've got some code which is slowing down I think
>because my data.frames are getting much larger - now approaching 1
>million rows by 50-100 columns - and my functions - originally written
>for much smaller data elements are sampling these data.frames a couple
>of layers down.
>
>    Before I rewrite them to do the sampling at the top level if there
>was a way to pass the address of the data.frame instead of the a copy
>of the whole thing then I suspect that would speed things up
>significantly.
>
>Thanks,
>Mark
>
>______________________________________________
>R-help at r-project.org mailing list
>https://*stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide http://*www.*R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.


-- 
--------------------------------------
Don MacQueen
Environmental Protection Department
Lawrence Livermore National Laboratory
Livermore, CA, USA
925-423-1062