Re: st: Counting the number of records in long format data

["Michael Blasnik" <michael.blasnik@verizon.net>]

Although egen sum() will get you what you want, it will do a bunch of work 
that you don't need it to.  A more direct way, which is also noticeably 
faster in large datasets, is:

bysort lpnr: gen totobs=_N

Michael Blasnik
michael.blasnik@verizon.net

----- Original Message ----- 
From: <wying1@umbc.edu>

> Try this?
>
> egen totobs = sum(1), by(lpnr)
>
> > Hi,
> >
> > I have a panel data set in long format. The identifying record variable 
> > is
> > called lpnr. Sometimes an observation occupies one row (that is, the
> > variables for this variable is only measured once), somtimes it occupies
> > two
> > rows (measured twice), sometimes three (measured three times) and so on.
> > However, I do not have a "time variable"--that is, a variable that counts
> > how many times (i.e. the number of rows) an observation appears? How can 
> > I
> > get this?
> >
> > Best regards,
> >
> > Christer
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