Hi!
Hi! I'm having issues summing by subject and date. I need the sum to reset to zero when encountering a new date (by subject). Here is my code;
data want;
set have;
by patient date;
if first.patient and res ^= . then targetsum=res;
else if res ^= . then targetsum+res;
output;
end;
run;
Here a sample of output for one subject. you can see the totals are not resetting with new date.
02OCT2017 81 81
02OCT2017 22 103
02OCT2017 39 142
11DEC2017 93 235
11DEC2017 23 258
11DEC2017 57 315
It's not clear that PROC SUMMARY does what you need. It will get you the total for each subject/date, but it will not give you a "running total" for all observations so far. Here is how you would modify your DATA step to do that:
data want;
set have;
by patient date;
if first.date then targetsum=0;
targetsum + res;
run;
proc summary data=have;
class patient date;
var res;
output out=want sum=;
run;
As indicated, don't use a data step, use a PROC designed to summarize the data.
If you need other variables included, look at PROC SUMMARY which can support adding in other variables in the output.
https://github.com/statgeek/SAS-Tutorials/blob/master/proc_means_basic.sas
It's not clear that PROC SUMMARY does what you need. It will get you the total for each subject/date, but it will not give you a "running total" for all observations so far. Here is how you would modify your DATA step to do that:
data want;
set have;
by patient date;
if first.date then targetsum=0;
targetsum + res;
run;
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