Hi, On Tue, Apr 15, 2008 at 12:09 PM, David Rijsman <[EMAIL PROTECTED]> wrote: <snip/> > I would expect the start of the second variable to be pruned from > [0,40] to [20,40] but what we see (when we run the attached file) is a > search on the start variable failing 20 times (trying start > 0,1,2,...19) before finding the first solution. Obviously I expect the > first decision to be a solution. Am I expecting to much propagation on > a task without compulsory part?
You are quite right in that there should be more pruning. I've looked into the code, and unfortunately there was a bug that made the pruning much weaker than it should have been (it never did anything wrong, just not enough). I've fixed the bugs I found in the trunk-version, and your example now has no failures. Thank you very much for the bug-report. If you don't want to use the trunk-version, send me an e-mail, and I'll send a diff of the relevant file to you. If you are planning to use cumulatives as a standard cumulative, you should know that there are other algorithms for cumulative that might give more pruning. In particular, edge-finding and not-first/not-last are commonly used. These are unfortunately not available in Gecode currently. Cheers, Mikael -- Mikael Zayenz Lagerkvist, http://www.ict.kth.se/~zayenz/ _______________________________________________ Gecode users mailing list [EMAIL PROTECTED] https://www.gecode.org/mailman/listinfo/gecode-users
