That -sum()- is better as -total()-. The old -egen- function -sum()- is
still there, but no longer documented.
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Nick Cox
Sent: 26 March 2008 16:15
To: [email protected]
Subject: RE: st: Re: Loop syntax
You can count occurrences of t > 0 separately by patient.
egen tcount = sum(t > 0), by(patient)
Then counting patients, not recordings, is possible e.g. by tagging, say
egen tag = tag(patient)
count if tag & tcount
For much more detail, see the thread started on 18 March by Daniel
McNeil.
Bill Gould gave the first principles answer, while I gave an -egen-
answer.
They are complementary.
Nick
Johannes Geyer
I have some results on 236 patients and each patient has 57 recordings
stored in a single variable t. I am trying to count how many of these
patients have a score of t>0. I tried the following code:
gen tcount=0
forvalues i=1/236{
forvalues j=1/57{
if patient==`i' & t>0 {
then tcount==tcount+1
continue
}
I think a loop is unnecessary here - you just want to count, right?
There
are many solutions, e.g.
count if t >0 & t<.
(saved in r(N))
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