[gecode-users] Extending Integer Variable

[Vincent Barichard]

Hi all,

Le mardi 8 avril 2008, Filip Konvička a écrit :
>
> > If you implement FloatVars, please keep us posted. If you want to
> > contribute to Gecode we would be more than happy to help!
>
> I'm happy to hear that. I do not have a precise plan yet, but I do need
> such variables. (I'm using IntVars now, but the model has some
> limitations because of that.) I first need to make some experiments with
> Boost.Intervals, because I think I'll need some rounding-error
> propagation - so it would be nice to reuse some existing work....and I
> already use Boost, so that would be the ideal choice. My intention is to
> do some simple implementation of FloatVars and some very basic
> propagators for addition, multiplication and relations (I need to be
> able to model basic arithmetic constraints).
>

I am also interested in implementing FloatVars. I already built a solver which 
works on floating variables using the MPFR library (http://www.mpfr.org/). I 
designed some propagators 
(+,-,*,/,max,min,cos,acos,sin,atan,asin,exp,log,sqr,sqrt) which work quite 
well on my benchmarks. 
I came to GeCode recently because of all the work done for the integer and set 
variables, but I will be glad to share my code with anyone who is interested 
in implementing FloatVars in GeCode.

Cheers,
Vincent

-- 
Vincent Barichard        Université d'Angers (LERIA)
Tel: 02 41 73 52 06      Département Informatique
Fax: 02 41 73 50 73      H203