topic Re: Filtering based on Date in SAS Programming

Filtering based on Date

Xing — Fri, 21 Jun 2019 17:31:24 GMT

data test;
	input admdate : mmddyy10. id @@;
	format admdate mmddyy10.;
	cards;
05/01/2009 1
08/01/2010 2
07/01/2012 3
08/24/2007 4
12/11/2012 5
;
run;

Currently, I have a dataset with date and id. I want to select all the observations that the date is within 1 year prior to 1/1/2013. That is I want to select all the obs with the date between 1/1/2012 and 1/1/2013. What should I do?

Thanks!

Re: Filtering based on Date

derekg — Fri, 21 Jun 2019 17:54:03 GMT

data test2;
	set test;
	where '01jan2012'd <= admdate <= '01jan2013'd;
run;

Re: Filtering based on Date

ballardw — Fri, 21 Jun 2019 18:00:37 GMT

Here are three ways that may work. They may need adjusting a little depending on whether the dates you mentioned as boundaries should be included or not.

data want;
   set test;
   /* between to specified dates*/
   where '01JAN2012'd le admdate lt '01JAN2013'd;
run;
data want2;
   set test;
   /* within a specified year*/
   where year(admdate) = 2012;
run;
data want3;
   set test;
   /* "year" as in from date*/
   where intck('year',admdate,'01JAN2013'd,'c') = 0;
run;

https://communities.sas.com/t5/SAS-Communities-Library/Working-with-Dates-and-Times-in-SAS-Tutorial/ta-p/424354 has a PDF with much information about dates.

Important: Any time you want to use a literal data is has to be in either DATE9. or DATE7. format, in quotes, with the D immediately following to tell SAS the value is a date literal value.

Re: Filtering based on Date

Xing — Fri, 21 Jun 2019 18:10:15 GMT

if the date is stored in a variable and I want to see 1 year prior to each date in this variable, what should I do?

Re: Filtering based on Date

ballardw — Fri, 21 Jun 2019 20:24:24 GMT

@Xing wrote:

if the date is stored in a variable and I want to see 1 year prior to each date in this variable, what should I do?

Are you asking "Given a specific date such as 21JUN2019, how do I get a SAS date value that is the same date one year ago?".

newdate = intnx('year',date,-1,'same');

if that is not what you want you need to provide a much more concrete example such as with actual dates and the desired result.

Really should look at this: https://communities.sas.com/t5/SAS-Communities-Library/Working-with-Dates-and-Times-in-SAS-Tutorial/ta-p/424354 has a PDF with much information about dates.