[gecode-users] Soft constraints

[Pierre Schaus]

I Martin,

Using semiring-based and other framework dedicated to soft constraints 
is not the only possibility.
Thierry Petit and JC-Régin have also worked on a representation of soft 
constraints by hard constraints so
that it can be used in existing software such as Gecode.
The web page of Thierry Petit is http://www.emn.fr/x-info/tpetit/
The idea is to add a variable to the hard constraint representing the 
violation of the constraint.
Willem has also worked on this subject 
(http://www.andrew.cmu.edu/user/vanhoeve/) with his famous soft alldiff 
with decomposition based violation measures.
Currently we also have a MS Student (Didier Loiseau) in Louvain -la 
-Neuve  who is currently implementing
the various softalldiff versions for Gecode. His email is didier.loiseau 
[at] student.uclouvain.be
I personally also work on soft statistical constraints such (Deviation 
and Spread) which can be very usefull for balancing
the violations among the soft constraints of your CSP.
Hope this help,

Pierre.









>
>
> Hi,
>
> I am sorry to ask totally unprepared about the topic but hope you 
> excuse. I've no deeper knowledge about soft constraints right now and 
> not checked the Gecode API seriously for that. :)
>
> Is there direct support for soft constraints in Gecode?
> If so where to start looking?
> If not is there an easy workaround to enable something similar? (Maybe 
> some literature to start with?)
>
> Sorry for asking without knowing much about the things I am intrested 
> in. But we are thinking about a student thesis based on soft constraints 
> and would like to implement it using Gecode.
>
> Thanks for any reply,
>
> Martin
>
>
>