topic Flag Based on Dates in SAS Programming

Flag Based on Dates

JoserT — Tue, 08 Oct 2019 16:29:44 GMT

Good morning,

I've been an SPSS user for a very long time and I now have to learn how to use SAS. I am having trouble creating a flag variable of enrolled based on dates.

I have the following data set:

id entry_date leave_date leave_code

1 2015-09-01 2016-07-01 L

2 2013-08-27 9999-12-31 N

3 2014-11-19 2015-02-28 L

4 2013-12-31 2016-09-15 T

I'm trying to do a 1 or 0, 1 indicating still enrolled. Basically if the leave date is eq 9999-12-31 student is still enrolled if the leave_date is gt 2016-06-30 then the student is still enrolled.

Any help on this would be greatly appreciated!

Re: Flag Based on Dates

novinosrin — Tue, 08 Oct 2019 16:38:37 GMT

data have;
input id  (entry_date  leave_date ) (:yymmdd10.)  leave_code $;
format entry_date  leave_date yymmdd10.;
cards;
1  2015-09-01  2016-07-01  L
2  2013-08-27  9999-12-31   N
3  2014-11-19  2015-02-28  L
4  2013-12-31  2016-09-15  T
;

data want;
set have;
Flag=leave_date eq '31dec9999'd or leave_date gt '30jun2016'd;
run;

Re: Flag Based on Dates

FelipeMosquetta — Tue, 08 Oct 2019 16:38:47 GMT

Hey, everything will depend on how formatted are your variables. Could you show us how they are?

Re: Flag Based on Dates

Tom — Tue, 08 Oct 2019 16:51:39 GMT

What did you try? The result of a boolean expression is going to be either 1 (true) or 0 (false);

31DEC9999 is also greater than 30JUN2016 so you probably just need one test.

data want;
  set have;
  flag = leave_date > '30JUN2016'd;
run;

Re: Flag Based on Dates

novinosrin — Tue, 08 Oct 2019 16:54:14 GMT

Good catch Sir @Tom Most embarrassing moment to not think that 31DEC9999 is also greater than 30JUN2016 . What a shame I caused to myself lol, Cheers though! 🙂