On Apr 22, 2009, at 3:42 PM, Bronagh Grimes wrote:
> Hi there,
> I am interested in converting SAS code to R & I wondered if anyone had
> any quick R code/tips for the following piece of test SAS code?
>
> Any feedback greatly appreciated.
>
> data A1;
> set A1;
> count + 1;
> by subject_id;
> if first.subject_id then count = 1;
> run;
There were several solution offered a couple of months back to the
challenge of replicating the features of the SAS _N_ construct. At
least that is my memory of how it looks in SAS. You probably have the
right books to consult for that question to construct a proper search:
http://search.r-project.org/nmz.html
David Winsemius, MD
Heritage Laboratories
West Hartford, CT