From: "Zheng_Jenny"
Subject: [NMusers] different results from two computers
Date: Mon, 14 Aug 2006 21:05:00 -0700

Dear all,
I have tried to run the same control file in two computers. One run minimized successfully and
another failed with the following message:
forrtl:error (73): floating divide by zero
Image            PC           Routine                    Line                 Source
run_test.ext   004014C2      Unknown                   Unknown               Unknnow
run_test.ext   00406947       Unknown                   Unknown               Unknnow
run_test.ext   00454679       Unknown                   Unknown               Unknnow
run_test.ext   0045CF46      Unknown                   Unknown               Unknnow
run_test.ext   004264C2      Unknown                   Unknown               Unknnow
run_test.ext   0041BF17      Unknown                   Unknown               Unknnow
Estimation omitted.
Would you please comment on the situation and more importantly, provide some advice? Thanks,

From: Mark Sale - Next Level Solutions com
Subject: RE: [NMusers] different results from two computers
Date: Wed, 16 Aug 2006 04:57:22 -0700

Nick et al
  Update on the stability of NONMEM/importance of successful
minimization.  After fixing a problem with the summation of the
likelihood, we have managed to make NONMEM converge successfully
indenpendent of sequence of subjects.  You may recall the discussion
that, for one problem at least, whether NONMEM converged was dependent
on the sequence of subjects in the data set.  Nick (appropriately)
cited this as some evidence of the lack of importance of successful
minimization, since for this this problem at least it seemed to be a
random event (since the sequence of subjects was randomly defined).  We
seemed to have solved that source of instability in NONMEM with some
fairly simple changes in the code, and now have a version of NONMEM VI
where convergence is independent of sequence of subjects in the data
set, and is essentially the best case from the 100 native NONMEM runs.
 Perhaps eventually, other sources of numerical instability will be
identified and we can all agree that minimization really does mean
something about the quality of the model/data set.  
 I'll post the results of the native NONMEM and the modified NONMEM on
my web site ( probably tomorrow.
 I'm looking for cases to try where this approach will make models that
refused to do a covariance step now will do one.  Anyone with
interesting, relatively fast problems (< 10 minutes) that fail
covariance, please contact me.

Mark Sale MD
Next Level Solutions, LLC

From: "Nandy, Partha [PRDUS]"
Subject: RE: [NMusers] different results from two computers
Date: Fri, 18 Aug 2006 17:17:35 -0400

Hi Mark,

Is this fix that you are talking about work for NONMEM V as well?  I have
several of the kind that you are interested in from NM-V, but none from NONMEM VI..

If you think it will be helpful, I can share some of these with you.

Kind Regards,

From: "jiang zhigang"
Subject: RE: [NMusers] different results from two computers
Date: Wed, 16 Aug 2006 23:02:23 +0800

I think the problem is the version of your compiler is old!
Upgrade it!
I hope this can help you!
Good Luck!