Hi Sorry about being a bit daft about all of this. With the change you suggested, I'll get the inner tensor product in the Power sum basis, right? And one more thing, I presume this is more of a sage-support question, but here it goes anyway : When I make a change in the code, do I have to recompile/rebuild or something?
Thanks for the help!! Best, Vasu On Jul 19, 3:49 pm, Mike Hansen <mhan...@gmail.com> wrote: > Hello, > > On Mon, Jul 19, 2010 at 3:29 PM, vasu <tewari.v...@gmail.com> wrote: > > For example, SF computes ( the code's not in maple, just to give an > > idea of the computation I was trying) > > > s=SFASchur(QQ) > > s[14,14].itensor(s[14,13,1]) > > > in "no time" . But it seems to take quite a lot of time on Sage. I > > have 4 gb memory and it ends up using 2+ gb for this particular > > computation ( if I remember correctly) > > > Any insights? > > The bulk of the time is converting back from the power-sum basis to > the Schur basis. With the following change, > > --- a/sage/combinat/sf/sfa.py > +++ b/sage/combinat/sf/sfa.py > @@ -1555,7 +1555,7 @@ > #Convert both self and x to the p basis > p = SFAPower(self.parent().base_ring()) > f = lambda part1, part2: zee(part1)*p(part1) > - return > self.parent()(p._apply_multi_module_morphism(p(self),p(x),f,orthogonal=True)) > + return p._apply_multi_module_morphism(p(self),p(x),f,orthogonal=True) > > internal_product = itensor > > I get > > sage: s = SFASchur(QQ) > sage: %time f = s[14,14].itensor(s[14,13,1]) > CPU times: user 5.25 s, sys: 0.04 s, total: 5.29 s > Wall time: 5.78 s > > When I first wrote this, I thought it'd be good to keep things in the > same basis, but there's too much of a performance impact. I think we > should make things as lazy as possible. > > --Mike -- You received this message because you are subscribed to the Google Groups "sage-combinat-devel" group. To post to this group, send email to sage-combinat-de...@googlegroups.com. To unsubscribe from this group, send email to sage-combinat-devel+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sage-combinat-devel?hl=en.
