Date:         Tue, 27 Oct 2009 06:49:01 -0400
Reply-To:     Daniel Fernandez <fdezdan@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Daniel Fernandez <fdezdan@GMAIL.COM>
Subject:      Re: Hospital attendance
Comments: To: Donald Harrison <donald.will.harrison@GMAIL.COM>

here my code:

data have;
input PAT_ID $  month1 month2 month3;
cards;
1 0 1 2
2 1 1 2
3 2 0 1
4 0 0 3
5 3 0 0
6 0 0 2
7 0 2 0
8 0 2 2
;;
run;

* I understand what you need is the sum of months result at the first month
with data
different than zero value;
data need;
set have ;
array monz(3) month1 - month3;
do y=1 to 3;
 if monz(y) NE 0 then
monz(y)=sum(of month:); else monz(y)=.;
end;
if (month3 > month2 and (month2 NE . OR month1 NE .)) then month3=.;
if (month2 > month1 and (month1 NE .)) then month2=.;
drop y;
run;


I hope it is helpful.
Daniel Fernandez.
Terrassa Hospital- Barcelona.