Hi Martin, It doesn't matter, both works: ES_FIX means that the propagator is at fixpoint wrt the current domain of the variables. ES_NOFIX differs only if the propagator performs some domain changes which it does not in your case: it means that the propagator is at fixpoint when it did not do any variable domain modifications otherwise it is not and will be re-executed at some point in time.
And yes, you should use advisors as they are more efficient: you save that the propagator is actually scheduled and executed. Cheers Christian -- Christian Schulte, Professor of Computer Science, KTH, www.ict.kth.se/~cschulte/ -----Original Message----- From: users-boun...@gecode.org [mailto:users-boun...@gecode.org] On Behalf Of Martin Mann Sent: Thursday, April 04, 2013 2:11 PM To: gecode user list Subject: [gecode-users] ExecStatus : what to return in case of no propagation Hi Gecoders, I have written a computationally expensive binary propagator that should be triggered only if one of the two constrained domains is smaller a certain threshold. Currently, I am enforcing this behaviour by subclassing the propagator from Gecode::BinaryPropagator<Gecode::Int::IntView,Gecode::Int::PC_INT_DOM> and doing the following in my propagate function ////////////////////////////////////////////////////////////////// propagate(Gecode::Space& home, const Gecode::ModEventDelta&) { // check if domain size limits are exceeded if (x0.size() > maxDomainSize && x1.size() > maxDomainSize) { // domains are too large, dont propagate for now return Gecode::ES_FIX; } ... normal propagation starts here } ////////////////////////////////////////////////////////////////// First question I have: do I have to return Gecode::ES_NOFIX or as I do ES_FIX in case of no propagation? Since I dont wont the propagator not to be called again until the domains are shrinked, I assume this to be a virtual fix point, right? Second question that came to me: is there a better way to get this domain size specific call behaviour e.g. via Advisor implementation etc? Thanks for your help, Martin -- Dr. Martin Mann, Postdoc assistant Bioinformatics - Inst. of Computer Science Albert-Ludwigs-University Freiburg Tel: ++49-761-203-8254 Fax: ++49-761-203-7462 http://www.bioinf.uni-freiburg.de/~mmann/ _______________________________________________ Gecode users mailing list users@gecode.org https://www.gecode.org/mailman/listinfo/gecode-users _______________________________________________ Gecode users mailing list users@gecode.org https://www.gecode.org/mailman/listinfo/gecode-users
