[gecode-users] Creating random binary constraints

[Guido Tack]

Hi Jérémie!

> Has anyone
> ever created propagators for these extensively represented
> constraints in Gecode ? If it is not the case, what do you
> think is the best way to implement this ? (actually, it seems
> not to be difficult to implement in  anaive way, but how about
> some smart way to manage this ?)

We don't currently have propagators for these constraints. Several
approaches have been proposed, e.g. GAC-Schema (J.C.Régin) and Box
Constraint Collections (Cheng, Lee, Stuckey). You may find further
references in these papers.
Depending on whether you need to make sure that these constraints are
propagated with domain consistency or not, you could of course resort to
reified constraints (poor propagation) or use the regular language
membership constraint available in Gecode (domain consistent but
inefficient for ad-hoc constraints).

Cheers,
   Guido

-- 
Guido Tack
http://www.ps.uni-sb.de/~tack