Hello ! >> I don't know.... Is it very costly to compute ? The Moebius function >> should be quick, shouldn't it ? O_o > > It is basically just self.lequal_matrix().inverse().change_ring(ZZ).
Oh. No Poset-specific algorithm. I see. Then we should earn a lot by doing so. > More general question: should we precalculate things like this? There is > some kind of memory-cpu tradeoff. Should lattices save meet and join > matrices? Or should there be some optional parameter, like I personally do not like such parameters. They behave like global variables, you never know what exactly you are changing... Hmmm.. But really, in the Poset class we are very very very far from having implemented correctly all that should be. Like the global caching that is enabled even if you never asked for it, the subsequent memory waste, like the matrices stored internally as Python things instead of C binary matrices. Really, I think that the way to go is to rewrite more efficiently whatever takes time, and that at the end of that you may not see the difference between compute=True and compute=False :-) Do you know the next operation that we should improve ? Nathann -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
