topic Re: flag nonidentical values within a group in SAS Health and Life Sciences

flag nonidentical values within a group

wcw2 — Tue, 05 Oct 2021 14:25:48 GMT

I need to do a data check that will flag any numeric values that are not identical to others in a group, see below. The first GROUPNO value of each group will always be correct. Thanks.

OBS GROUPNO FLAG (want)
1 6
2 6
3 6
4 5 x
5 6
6 6
7 6
8 20
9 21 x
10 20
11 20
12 20

Re: flag nonidentical values within a group

FreelanceReinh — Tue, 05 Oct 2021 15:01:44 GMT

Hello @wcw2,

You'll need an additional variable (like variable grp in the example below) designating the groups or some other criterion to tell SAS where a new group begins.

data have;
input grp GROUPNO;
cards;
1 6
1 6
1 6
1 5
1 6
1 6
1 6
2 20
2 21
2 20
2 20
2 20
;

data want(drop=_g1);
set have;
by grp;  /* add NOTSORTED option if needed */
if first.grp then _g1=groupno;
else if groupno ne _g1 then FLAG='x';
retain _g1;
run;

Re: flag nonidentical values within a group

wcw2 — Tue, 05 Oct 2021 15:16:28 GMT

Yes indeed. Thanks so very much!