It is indeed what David wants, but
-profiler- neither promises to
give this information nor in
fact gives it.
"The record includes only the time spent
directly in a program and not time spent
in other programs that are themselves
invoked by the program -- these latter
times are recorded with the invoked program."
You may be carrying over ideas associated
with -for- in other languages in which
-for- controls a loop. -for- in Stata
does that too, but it is nothing other
than an .ado that runs other commands
or programs. (There also can be a major
interpretive overhead. I used to use
-for- a long time ago to cycle over
stuff, until it became clear that -for-
itself was sometimes taking many times longer
than what I wanted.)
In this respect, -for- contrasts sharply
with -foreach- or -forvalues-, which
are wired into the executable. Having
said that, I am not clear that using
-foreach- here would get the profiling
desired.
Nick
[email protected]
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of
> Mark Schaffer
> Sent: 14 November 2004 16:27
> To: [email protected]
> Subject: RE: st: time elapsed within 'for' loops
>
>
> Nick/David,
>
> Quoting Nick Cox <[email protected]>:
>
> > I doubt it. -for- itself is a command. The fact
> > that it runs other commands is not reflected
> > by what the profiler reports,
>
> reshape is an ado, and so profiler should report on how much
> time was spent
> in reshape, no? I think this is what David wants. Or
> perhaps I missed the
> point somewhere.
>
> Cheers,
> Mark
>
> > as is explained
> > in the help Mark quotes here.
> >
> > A quite different comment is beware -for-
> > and the habit of trying to write miniature programs
> > as a single call to -for-. It is cute when it
> > works but very inefficient and all too likely to bite you.
> >
> > Nick
> > [email protected]
> >
> > Mark Schaffer
> >
> > > Try -profiler-; it will probably do what you want. From the
> > > help file:
> > >
> > > "profiler is a programmer's command that can help in
> > > optimizing ado-files
> > > and other Stata programs. When profiling is turned on,
> > > profiler on, Stata
> > > begins keeping a record of each time a program is run and how
> > > much time is
> > > spent in the program."
> >
> > David K Evans
> >
> > > > Is there a simple way to see how much time has elapsed while a
> > > > command in the midst of a "for" loop is running?
> > > >
> > > > Outside of a loop, I just "set rmsg on" and can see how long
> > each
> > > > command takes.
> > > >
> > > > But if I have, for example,
> > > >
> > > > for num 1/10: preserve \ keep if age==X \ reshape [blah blah
> > blah]
> > > > \
> > > > save ageX.dta, replace \ restore;
> > > >
> > > > and I want to know how long the reshaping took, I'm not sure how
> > to
> > > > find out. "set rmsg on" only gives me the time for the entire
> > loop.
> > > >
> > > > I know about macros to display the time, but I'm not sure how
> > to
> > > > manipulate them to calculate time elapsed.
> >
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