On Fri, Jul 31, 2015 at 8:36 AM, Pierre <pierre.guil...@gmail.com> wrote: > Hi, > > I have asked a version of this question here: > > https://groups.google.com/forum/#!topic/sage-support/2KJQhOf-N7Y > > However I now have a minimal working example, and sage-devel is perhaps > better than sage-support for this question (is it?) > > So when working with multivariable polynomials over ZZ and taking the sum of > two ideals, things are inexplicably slow on sagemathcloud. Try the > following: > > S.<a, b>= ZZ[] > L= [ S.random_element() for i in range(500) ] > def test(): > foo= []*S > for P in L: > foo= foo + [P]*S > > %timeit test() > > On my local machine (macbook with sage 6.2), which for anything else is > slower than the cloud, i get about 170ms (i've tried it with L reconstructed > a few times). > On sagemathcloud, it's about 3.8 seconds. 20 times slower ! > > Using %prun, it seems that a lot of time is spend by {map} ... ???? > > Also note that on the cloud, there is a warning message about computations > over ZZ, using singular, not being trustworthy. Sage 6.2 doesn't have that. > Could it have an effect on the speed? > > Anyway, just wanted to point this out. It would be lovely if this could be > fixed as some point. I'm really enjoying the cloud !
This isn't really a question relevant to SageMathCloud. It's a question about Sage-6.7 (which is the current version in the cloud) and Sage-6.2, which is what you're comparing with. I would not be surprised if you were to do the same test on Sage-6.7 on your laptop, if it would also be slow. It is, of course, a good question to be asking. I hope somebody will run your benchmark on a sage-6.7 install not in SageMathCloud and report. I will upgrade SMC to sage-6.8 sometime soon -- I don't know if that will help. -- William > > Thanks, > Pierre > > > -- > 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. -- William (http://wstein.org) -- 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.
