SAS - creating indicator variables - sas

Question

I'm using SAS and I'd like to create an indicator variable.
The data I have is like this (DATA I HAVE):
and I want to change this to (DATA I WANT):
I have a fixed number of total time that I want to use, and the starttime has duplicate time value (in this example, c1 and c2 both started at time 3). Although the example I'm using is small with 5 names and 12 time values, the actual data is very large (about 40,000 names and 100,000 time values - so the outcome I want is a matrix with 100,000x40,000.)
Can someone please provide any tips/solution on how to handle this?

Answer 1

40k variables is a lot. It will be interesting to see how well this scales. How do you determine the stop time?
data have;
input starttime name :$32.;
retain one 1;
cards;
1 varx
3 c1
3 c2
5 c3x
10 c4
11 c5
;;;;
run;
proc print;
run;
proc transpose data=have out=have2(drop=_name_ rename=(starttime=time));
by starttime;
id name;
var one;
run;
data time;
if 0 then set have2(drop=time);
array _n[*] _all_;
retain _n 0;
do time=.,1 to 12;
output;
call missing(of _n[*]);
end;
run;
data want0 / view=want0;
merge time have2;
by time;
retain dummy '1';
run;
data want;
length time 8;
update want0(obs=0) want0;
by dummy;
if not missing(time);
output;
drop dummy;
run;
proc print;
run;

Answer 2

This will work. There may be a simpler solution that does it all in one data step. My data step creates a staggered results that has to be collapsed which I do by summing in the sort/means.
data have;
input starttime name $;
datalines;
3 c1
3 c2
5 c3
10 c4
11 c5
;
run;
data want(drop=starttime name);
set have;
array cols (*) c1-c5;
do time=1 to 100;
if starttime < time then cols(_N_)=1;
else cols(_N_)=0;
output;
end;
run;
proc sort data=want;
by time;
proc means data=want noprint;
by time;
var _numeric_;
output out=want2(drop=_type_ _freq_) sum=;
run;
I am not recommending you do it this way. You didn't provide enough information to let us know why you want a matrix of that size. You may have processing issues getting it to run.
In the line do time=1 to 100 you can change that to 100000 or whatever length.

Answer 3

I think the code below will work:
%macro answer_macro(data_in, data_out);
/* Deduplication of initial dataset just to assure that every variable has a unique starting time*/
proc sort data=&data_in. out=data_have_nodup; by name starttime; run;
proc sort data=data_have_nodup nodupkey; by name; run;
/*Getting min and max starttime values - here I am assuming that there is only integer values form starttime*/
proc sql noprint;
select min(starttime)
,max(starttime)
into :min_starttime /*not used. Use this (and change the loop on the next dataset) to start the time variable from the value where the first variable starts*/
,:max_starttime
from data_have_nodup
;quit;
/*Getting all pairs of name/starttime*/
proc sql noprint;
select name
,starttime
into :name1 - :name1000000
,:time1 - :time1000000
from data_have_nodup
;quit;
/*Getting total number of variables*/
proc sql noprint;
select count(*) into :nvars
from data_have_nodup
;quit;
/* Creating dataset with possible start values */
/*I'm not sure this step could be done with a single datastep, but I don't have SAS
on my PC to make tests, so I used the method below*/
data &data_out.;
do i = 1 to &max_starttime. + 1;
time = i; output;
end;
drop i;
run;
data &data_out.;
set &data_out.;
%do i = 1 %to &nvars.;
if time >= &&time&i then &&name&i = 1;
else &&name&i = 0;
%end;
run;
%mend answer_macro;
Unfortunately I don't have SAS on my machine right now, so I can't confirm that the code works. But even if it doesn't, you can use the logic in it.