[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Help-glpk] gmpl manual

From: Andrew Makhorin
Subject: Re: [Help-glpk] gmpl manual
Date: Wed, 19 Mar 2008 11:09:29 +0300

> Are there other manuals on GMPL?

You can try to find some educational materials in the internet.

>  I could not find out in the GMPL
> manual how to get the number of constraints, parameters, variables
> etc. read into the model. Also, I could not see how it may be possible
> to create intermediary values (are they called Macros?, as MPL does
> call them...) out of parameters or variables or combined.

> Is GMPL 100% AMPL compatible? May I use AMPL manuals out there,
> without not much hesitation?

GNU MathProg is a subset of AMPL. The most relevant document (in the
sense that all features described there are implemented in MathProg)
is the following:

R. Fourer, D. M. Gay, B. W. Kernighan, "AMPL: A Mathematical
Programming Language", 1990.

This document is publically available at:

> I read that "... the mathprog translator is greedy to the memory
> ..." and actually I am having problem getting the model generated for
> a large instance. glpsol runs out of memory on a machine with 1.5GB of
> memory before half of the constraints are generated.

GLPK implementation of the MathProg language is not very efficient,
so huge models cannot be processed by the translator.

> One reason I am
> learning GMPL is to be able to use GLPK. Would you recommend me an
> other language in that case?

Which language do you mean? Programming language or modeling one?

> Or can I use glpsol to convert the model
> from GMPL to MPS not using the mathprog translator?

In glpsol there is no way to translate MathProg models to MPS format
other than using the MathProg translator.

> Hopefully this message was not off topic but are there other mail
> lists, forums, etc. on GNU Math Programming Language?

AFAIK, no.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]