Trying to have first observation within a group (name AND ID) carry down

[KPCklebspn]

Dataset looks like this -

Name  ID  flag1. 

AJ      1     1

AJ      1     .

AJ      1     .

AJ      2     .

How do I make dataset looks like this -

Name  ID  flag1.  varWant

AJ      1     1         1

AJ      1     .          1

AJ      1     .          1

AJ      2     .          .

Thanks!

[KPCklebspn]

To clarify - I want the first obs for flag within a group (name AND ID) to carry down

[Astounding · Accepted solution]

As long as your data set is sorted by Name and ID:

data want;

set have;

by name id;

if first.id or flag1 > . then varWant = flag;

retain varWant;

run;