topic how to get first obs value of start date and last obs value of end date where multiple obs present in SAS Programming

how to get first obs value of start date and last obs value of end date where multiple obs present

knveraraju91 — Wed, 12 Apr 2017 03:35:58 GMT

Dear,

In my data, each subject has startdate(sdate) enddate(edate) of dose of a drug taken. For the derivation an variable I need an output dataset with first.sdate of each subject and last.edate of each subject. Thank you

output need;

id sdate edate

1 05OCT2015 30OCT2015

2 05OCT2015 29OCT2015

3 06OCT2015 25OCT2015

data one;
input id sdate  edate date9.
datalines;
1 05OCT2015 06OCT2015
1 06OCT2015 17OCT2015
1 17OCT2015 30OCT2015
2 05OCT2015 10OCT2015
2 11OCT2015 20OCT2015
2 20OCT2015 25OCT2015
2 26OCT2015 29OCT2015
3 06OCT2015 17OCT2015
3 17OCT2015 25OCT2015
;

Re: how to get first obs value of start date and last obs value of end date where multiple obs prese

novinosrin — Wed, 12 Apr 2017 03:59:50 GMT

data one;
input id sdate : date9. edate :date9.;
format sdate edate date9.;
datalines;
1 05OCT2015 06OCT2015
1 06OCT2015 17OCT2015
1 17OCT2015 30OCT2015
2 05OCT2015 10OCT2015
2 11OCT2015 20OCT2015
2 20OCT2015 25OCT2015
2 26OCT2015 29OCT2015
3 06OCT2015 17OCT2015
3 17OCT2015 25OCT2015
;

data want;
set one;
by id;
retain _sdate;
if first.id then _sdate=sdate;
else if last.id then sdate=_sdate;
if last.id;
drop _sdate;
run;

Regards,

Naveen Srinivasan

Re: how to get first obs value of start date and last obs value of end date where multiple obs prese

user24feb — Wed, 12 Apr 2017 06:48:44 GMT

Try:

Proc SQL;
  Create Table Want As
    Select id,
	  Min(sdate) as sdate Format=Date9.,
	  Max(edate) as edate Format=Date9.
    From one
    Group By id;
Quit;

Re: how to get first obs value of start date and last obs value of end date where multiple obs prese

ballardw — Wed, 12 Apr 2017 15:49:31 GMT

If there are no other variables involved:

proc summary data=have nway;

class id;

var sdate edate;

ouput out=want(drop= _:) min(sdate)= max(edate)=;

run;