Re: [Help-glpk] loop for for mathprog

[Michael Hennebry]

On Tue, 14 Nov 2006, Andrew Makhorin wrote:

> There is a dilemma, because I do not think that mixing modeling
> and "programming" capabilities within model description (as in
> AMPL) is a good idea; on the other hand I would like to keep
> compatibility between GNU MathProg and AMPL. Probably, there must be
> another level, something like a script, that allows performing all
> operations needed for reoptimization and post-optimal processing.

In my optimization work, I almost always use the
API of a solver instead of a modeling language.
The reason is that I usually want to solve another
problem related to the first and its solution.
Absent a reliable mechanism for converting variable
names to variable indices this can be difficult.
Being able to do the following from within code would be a good thing:
read a problem specified in a modeling language
solve problem
update problem
solve problem
rinse and repeat as necessary
print solution in convenient form.

Being able to convert names to indices would facilitate
the update problem and print solution steps.

It's been a release or two since I last used GLPK,
so if it now has and documents the aforementioned mechanism,
never mind.

-- 
Mike   address@hidden
"it stands to reason that they weren't always called the ancients."
                                                      --  Daniel Jackson