Project : coprin

Section: New Results

Keywords : solving framework , algorithm specification .

Driving language for constraints solving algorithms

Participants : Gilles Chabert, Gilles Trombettoni, David Daney, Yahia Lebbah, Jean-Pierre Merlet, Claude Michel, Bertrand Neveu, Yves Papegay, Michel Rueher.

The subject of Gilles Chabert's internship was to design a driving language for constraint solving algorithms over the reals. We decided to first reduce the field of study to the classic box reduction methods introduced by the constraint programming community, which embraces hull-consistency, box-consistency and stronger properties (3B, Bound,...). We obtained a small language, simple enough to define those methods in a few lines of code. This language is fine-grained enough to build whatever new sequence of the underlying functions (as constraint evaluation, projection, or interval shaving).

We have also implemented a prototype for this language, in order to check its completeness, verify that the execution results match those obtained with existing solvers, and eventually test the benefits of particular programs corresponding to new kinds of reductions.

This work is the first step of a larger project of an open platform for constraint solving, in which Gilles Chabert's PHD work will take part.