My Constraint Programming Blog

JaCoP version 3.1 has been released. Download information is here. (Sourceforge)

From the announcement:

Dear users,

We have just released JaCoP 3.1. This is a release that fixes few bugs as well as provides a new Binpacking constraint. The Binpacking constraint allows modeling of problems exhibiting bin packing problem structure. The addition of this constraint introduced changes to minizinc/fz library in JaCoP since the definitions of bin_packing.mzn, bin_packin_capa.mzn and bin_packing_load.mzn have been added. The JaCoP guide has been updated to explain how to use Binpacking constraint.

best regards, Core Developer Team

Don't forget that there is a SVN version as well.

Posted by hakank at 10:52 PM | Permalink

Today the MiniZinc Challenge 2011 (the fourth) was announced:

The aim of the challenge is to start to compare various constraint solving technology on the same problems sets. The focus is on finite domain propagation solvers. An auxiliary aim is to build up a library of interesting problem models, which can be used to compare solvers and solving technologies.

Entrants to the challenge provide a FlatZinc solver and global constraint definitions specialized for their solver. Each solver is run on 100 MiniZinc model instances. We run the translator mzn2fzn on the MiniZinc model and instance using the provided global constraint definitions to create a FlatZinc file. The FlatZinc file is input to the provided solver. Points are awarded for solving problems, speed of solution, and goodness of solutions (for optimization problems).

See the MiniZinc Challenge 2011 -- Rules for more details. Note, for example, that the scoring procedure has been changed from previous competitions.

If you haven't, now can be a good time to read the paper Philosophy of the MiniZinc Challenge by Peter J. Stuckey, Ralph Becket, Julien Fischer (from 2010) that discuss the MiniZinc Challenge is more detail.

Posted by hakank at 07:35 AM | Permalink