topic Flag set to 1 in SAS Programming

Flag set to 1

SASPhile — Wed, 04 Oct 2017 20:07:04 GMT

subjectid term
1001
1001
1001 lost
1002 screen
1002 random
1002
1003 screen
1003 random
1003 lost
how to set flag to 1 for the below condition?
if a subject has multiple records and only one record is not null then flag should set to 1
in this case 1001 can have flag 1.

Re: Flag set to 1

Reeza — Wed, 04 Oct 2017 20:17:04 GMT

Run a proc freq or means on the data by ID to get the number of missing. Merge data back in and create flag.

Re: Flag set to 1

Astounding — Wed, 04 Oct 2017 21:19:27 GMT

Since you didn't give all the details about when FLAG should be 1 (all 1001 observations, just the non-null one, just the last one?), I'll do it in the easiest possible way. FLAG will be 1 on the last observation for a SubjectID, if there is only one non-null value.

This assumes your data set is already in order by SubjectID:

data want;

set have;

by subjectID;

if first.subjectID then non_null=0;

if term > ' ' then non_null + 1;

if last.subjectID=1 and first.subjectID=0 and non_null = 1 then flag=1;

drop non_null;

run;

****************************************

EDITED: Revised so the non-null value gets flagged (not as easy, of course):

data want;

n_recs=0;

non_null=0;

do until (last.subjectID);

set have;

by subjectID;

n_recs + 1;

if term > ' ' then non_null + 1;

end;

do until (last.subjectID);

set have;

by subjectID;

if term > ' ' and non_null=1 and n_recs > 1 then flag=1;

else flag=.;

output;

end;

drop n_recs non_null;

run;

Re: Flag set to 1

SASPhile — Wed, 04 Oct 2017 20:59:25 GMT

not just the last record, the non null value.

if 1001 has a value in the second record and first and last records are null, then the non null record has to have a flag

Re: Flag set to 1

Reeza — Wed, 04 Oct 2017 21:10:22 GMT

Show it.

@SASPhile wrote:

not just the last record, the non null value.

if 1001 has a value in the second record and first and last records are null, then the non null record has to have a flag

Re: Flag set to 1

SASPhile — Wed, 04 Oct 2017 21:14:49 GMT

subj term flag
1001
1001 lost 1
1001
1002 lost 1
1002 screen 1
1002
1003
1003
1003 random 1
1004 lost 1

Re: Flag set to 1

HB — Wed, 04 Oct 2017 21:41:45 GMT

So your flag is any record with a nonnull value of TERM?

Re: Flag set to 1

SASPhile — Wed, 04 Oct 2017 21:45:54 GMT

yes

Re: Flag set to 1

Reeza — Wed, 04 Oct 2017 21:48:41 GMT

if not missing(term) then flag=1;

Re: Flag set to 1

HB — Wed, 04 Oct 2017 21:54:25 GMT

Might not even need a flag.

Data want;

set have;

if not missing(term);

code here

run;

Re: Flag set to 1

Ksharp — Thu, 05 Oct 2017 06:55:22 GMT

data have;
infile cards truncover;
input subjectid    term $;
cards;
1001
1001
1001             lost
1002             screen
1002              random
1002
1003                  screen
1003               random
1003                   lost
;
run;
proc sql;
select *,n(term)=1 as flag
 from have
  group by subjectid;
quit;