Date:         Thu, 8 Jan 2004 15:19:46 GMT
Reply-To:     julierog@ix.netcom.com
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Roger Lustig <trovato@VERIZON.NET>
Subject:      Re: Working with dates
Content-Type: text/plain; charset=us-ascii; format=flowed

Dear Jen:
Try this.

data new;
flag=0;                    *** Reset flag for new person;
do until (last.person_id); *** Loop through one person's data;
set old;                   *** Get a record;
by person_id;              *** allow LAST.<var> processing;
if flag=0 then output;     *** If prev. record didn't have the key date,
                            ***  then we can output this one.;
if end='30oct2003'd then flag=1; *** But only the 1st one with key date;
end;                       *** End of loop for one person's data;
run;                       *** Go to top of DATA step to reset flag;

OK?

Roger

Jennifer R Popovic wrote:
> I have a dataset of begin and end dates of an event, multiple events per
> person.  I've pasted an example of one person's data below (sorted by
> begin date).  What I need to do for each person is to make the first obs
> with an END date of 10/30/2003 the last observation for that person. So
> for the person below, the fifth obs would be the last b/c I'd want to
> delete the last three obs.
> I know there must be an easy way to do this, but for some reason can't
> seem to make it work.  Any suggestions?
>
> obs     begin       end
> 1       04/24/2001  04/28/2001
> 2       09/09/2001  12/19/2001
> 3       02/18/2002  03/29/2002
> 4       04/23/2002  04/27/2002
> 5       10/10/2002  10/30/2003
> 6       01/08/2003  01/09/2003
> 7       02/25/2003  10/30/2003
> 8       07/14/2003  10/30/2003
>
> Thanks,
> Jen