topic Re: Coding Group Numbers in SAS Programming

Coding Group Numbers

EB1 — Wed, 09 Dec 2015 15:50:04 GMT

Hi all,

I am trying to make a variable 'B' that will code each of the lines of A by group number. I want it to code B=1 for the first group of the first day when when A=1, B=2 for the second group of that day when A=1, etc. I need this counter to restart the next day (and by next participant). Any ideas on how to get this to work? Thank you!

Data I have:

ID Day A
1 1 1
1 1 1
1 1 .
1 1 1
1 1 1
1 1 1
1 1 .
1 2 .
1 2 1
1 2 1
1 2 .
1 2 1
1 2 .
2 1 1
2 1 1
2 1 1
2 1 .
2 1 .
2 1 1
2 1 1
2 2 1
2 2 .
2 2 1

Data I want:

ID Day A B
1 1 1 1
1 1 1 1
1 1 . .
1 1 1 2
1 1 1 2
1 1 1 2
1 1 . .
1 2 . .
1 2 1 1
1 2 1 1
1 2 . .
1 2 1 2
1 2 . .
2 1 1 1
2 1 1 1
2 1 1 1
2 1 . .
2 1 . .
2 1 1 2
2 1 1 2
2 2 1 1
2 2 . .
2 2 1 2

Re: Coding Group Numbers

ballardw — Wed, 09 Dec 2015 16:07:16 GMT

This works for your example. Sort order might be an issue with more complex data.

/* to make a data set of example data to test*/
data have;
   input id day a;
datalines;
1     1       1
1     1       1
1     1        .
1     1       1
1     1       1
1     1       1
1     1        .
1     2        .
1     2       1
1     2       1
1     2        .
1     2       1
1     2        .
2     1       1
2     1       1
2     1       1
2     1        .
2     1        .
2     1       1
2     1       1
2     2       1
2     2       .
2     2       1
;
run;

data want;
   set have;
   by id day notsorted A;
   retain group;
   drop group ;
   if first.day then group=0;
   if first.a and a>0 then group+1;
   if not missing(A) then b=group;
run;

Re: Coding Group Numbers

EB1 — Wed, 09 Dec 2015 16:27:18 GMT

This works perfectly, thank you!