[Help-glpk] GLPK 4.38 for Java under Linux

[Sylvain Fournier]

Hi,

I have been working with GLPK for 2 or 3 months, and I´d really like to congratulate all the people that contribute to the development of this solver.
In fact, I am working with Java, and most of the time under Linux. But I need to have my code run under Windows as well. As I am not sure there is a GLPK for Java under Linux delivered with the Gnu release, I use a Java interface found on the following website: http://bjoern.dapnet.de/glpk/

As this Java interface was written for a version of GLPK rather old (4.8), I had to modify it for my own purposes and re-compile both the .jar and the .so, but it was ok on Linux. For the time being, however, I didn´t manage to compile the .dll on Windows yet (I don´t have enough knowledge in compiling shared libraries).

I then saw that there is a glpk_4_38_java library available (http://winglpk.sourceforge.net/), I tried it on Windows and it seems to work fine. But there is a problem of organization in my code, as I use a different Java interface when running on Linux and when running on Windows.
So finally, my question on this subject is: is there a Java interface equivalent as the one found at http://winglpk.sourceforge.net/, but for Linux? In other words, has the glpk_4_38_java.dll also been compiled under Linux as a .so?
The question could be also: has the Java interface found at http://bjoern.dapnet.de/glpk/ been updated by someone for the latest versions of GLPK?

I have another question about my algorithm. I am using a Branch&Price scheme. When I add variables, I want to use the basis of the previous run as the first basis of the current run (I don´t want to solve the model from scratch each time!) When I delete columns however, it may occur that one of them was in the basis, that consequently is not valid any more.
Is there a simple way for me to use the same basis in the next run in case it was not modified, and update this basis in the case it has lost at least one variable? (I used the warm_up function and I was looking at its return code, but this function seems to be deprecated on the newest versions.)

If you want more information,  feel free to ask!

Sylvain Fournier

Date: Sat, 2 May 2009 16:32:01 +0300
From: Andrew Makhorin <address@hidden>
Subject: [Help-glpk] glpk 4.38 release information
To: address@hidden
Message-ID: <address@hidden>
Content-Type: text/plain; charset=us-ascii

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GLPK 4.38 -- Release Information
********************************

Release date: May 02, 2009

GLPK (GNU Linear Programming Kit) is intended for solving large-scale
linear programming (LP), mixed integer linear programming (MIP), and
other related problems. It is a set of routines written in ANSI C and
organized as a callable library.

In this release:

       API routines glp_read_mps and glp_write_mps were improved.

       Some improvements were made in the dual simplex routines.

       Two external software modules AMD and COLAMD were included in
       the distribution (for more details please see src/amd/README
       and src/colamd/README). Now they are used in the interior-point
       solver to reorder the matrix prior to Cholesky factorization.

       API routine glp_ipt_status may return two new statuses due to
       changes in the routine glp_interior. For details please see the
       reference manual included in the distribution.

       A minor bug was fixed in the graph/network routines. Thanks to
       Nelson H. F. Beebe <address@hidden> for bug report.

See GLPK web page at <http://www.gnu.org/software/glpk/glpk.html>.

GLPK distribution can be ftp'ed from <ftp://ftp.gnu.org/gnu/glpk/> or
from some mirror ftp sites; see <http://www.gnu.org/order/ftp.html>.

MD5 check-sum is the following:

83d4b345800b3f30e4ef570216f94fbe *glpk-4.38.tar.gz

GLPK is also available as a Debian GNU/Linux package. See its web page
at <http://packages.debian.org/etch/glpk>.
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