From bates at stat.wisc.edu  Tue Nov 16 22:52:06 2010
From: bates at stat.wisc.edu (Douglas Bates)
Date: Tue, 16 Nov 2010 15:52:06 -0600
Subject: [Rd] DBLEPR?
In-Reply-To: <4CE2EAF7.5020202@uottawa.ca>
References: <4CE2EAF7.5020202@uottawa.ca>
Message-ID: <AANLkTimbP_BfXjzjXNqkJq7a4=Mu_rr9r6UXyTogsEfd@mail.gmail.com>

On Tue, Nov 16, 2010 at 2:35 PM, Prof. John C Nash <nashjc at uottawa.ca> wrote:
> I normally see digest once per day, but got msg from Doug Bates so responding with context.

> UCMINF is a package on CRAN that implements a variable metric minimizer.

A pedant might point out that the package is called "ucminf".

> It does quite
> well on unconstrained problems. Stig Mortensen packaged the Fortran version for R, but is
> not at moment responding to emails. There's also a Matlab version. We have it in optimx
> and get some occasions where it just stops if we set trace>0. Other times we can't get it
> to fail. My guess is something like an undefined variable or a bad declaration of a
> pointer, but C and C++ are not languages I've much experience with.

Well, it doesn't work well for me because my version of gfortran (GNU
Fortran (Ubuntu/Linaro 4.4.4-14ubuntu5) 4.4.5) objects to the format
strings in some of the Fortran WRITE statements.

The recommended approach is to avoid all Fortran I/O including writing
to a Fortran character array.   As there are only 3 such WRITE
statements in the Fortran code it would be very simple to replace them
with calls to C functions that in turn call Rprintf.  However, it
would be best if Stig could take ownership of the modifications.



[Rd] DBLEPR?
Douglas Bates