Hi David, Let me try to give some reasonable answers:
- I am not sure whether I really get the first question. But yes, in this situation the AFC of a _propagator_ can only increase. - You are right, the AFC of a _variable_ can in fact decrease in the cases you describe. It even makes sense: the variable has become less difficult as less propagators that have failed in the past depend on it. Actually, your idea of deducing something from the AFC before and after sounds quite interesting. I would be very interested to know whether this works for you. Best Christian -- Christian Schulte, www.ict.kth.se/~cschulte/ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of David Rijsman Sent: Wednesday, June 23, 2010 10:57 AM To: [email protected] Subject: [gecode-users] Accumulated failure count and variables part of a failure Hi All, I am trying to expose as many as possible variables which are part of a propagator which triggered a failure. Before I execute a branch I store the accumulated failure count of all variables. Next I execute the branch and assume this one fails. Right after failing I query the accumulated failure count of the variables in the failed space, if it has increased I know the variable is part of the propagator that triggered the failure (if no constraints have been added). Is it true that the accumulated failure count of the variable can only increase because it has been part of the propagator which was part of the propagator which triggered the failure? I can see some problems which is if a propagator cancels an advisor on a variable or if the propagator is entailed, this decreases the accumulated failure count. This can happen before the failure was triggered and therefor the afc of a variable can decrease although it is part of a propagator which failed. Is this correct? If I would query the space which has been 'recomputed' to execute the alternative of the branch which triggered the failure, the afc compared to before the failure happened would be a good indicator if the variable was part of a failure, do you agree? David _______________________________________________ Gecode users mailing list [email protected] https://www.gecode.org/mailman/listinfo/gecode-users _______________________________________________ Gecode users mailing list [email protected] https://www.gecode.org/mailman/listinfo/gecode-users
