topic Re: adding group number, use retain? or do loop? in SAS Programming

adding group number, use retain? or do loop?

Ken_oy — Tue, 19 Nov 2013 22:16:11 GMT

I want to add a group number to the first dataset (see the second one). Does anyone know how?

I cannot use sort because some categories have the same name. I can only determine the group by the existing data order.

Thanks!

dataset 1:

dataset 2:

a 1

b 2

c 3

d 4

b 5

Peter_C — Tue, 19 Nov 2013 22:29:44 GMT

set statement referring to a single dataset allows the by statement to use the NOTSORTED option

ballardw — Tue, 19 Nov 2013 22:29:53 GMT

If the two datasets have the exact same number of records then this may work:

data new;

set dataset1;

set dataset2;

run;

Reeza — Tue, 19 Nov 2013 22:32:08 GMT

Use the NOTSORTED option of by groups with a retain statement:

data want;

set have;

by id notsorted;

retain group 0;

if first.id then group=group+1;

run;

Peter_C — Tue, 19 Nov 2013 22:39:12 GMT

A simple version would be

data ds2 ;

set ds1 ;

by id notsorted ;

group_no + first.id ;

run ;

Ken_oy — Wed, 20 Nov 2013 15:01:32 GMT

I make my own version too, thank you all for the ideas!

data want;

set test;

retain group 0;

if lag( id ) ne id then group +1;

run;