On Thu, Aug 23, 2012 at 05:43:27PM +0200, Nicolas M. Thiery wrote: > As for the room for improvement, for Weyl character rings, but also > for everything using root systems intensively, like Weyl groups and > the like, a big spot is the optimization of CombinatorialFreeModule in > small dimension by using a dense representation.
As a first step, see http://trac.sagemath.org/sage_trac/ticket/13406: Converting a CombinatorialFreeModule element to a vector (e.g. dense FreeModule element) was ridiculously slow: Before: sage: sage: F = CombinatorialFreeModule(QQ, range(10)) sage: f = F.an_element() sage: %timeit f._vector_() 625 loops, best of 3: 142 µs per loop sage: %timeit f.to_vector() 625 loops, best of 3: 143 µs per loop sage: %timeit vector(f) 625 loops, best of 3: 159 µs per loop After: sage: F = CombinatorialFreeModule(QQ, range(10)) sage: f = F.an_element() sage: %timeit f._vector_() 625 loops, best of 3: 18.4 µs per loop sage: %timeit f.to_vector() 625 loops, best of 3: 18.5 µs per loop sage: %timeit vector(f) 625 loops, best of 3: 34.6 µs per loop This impacts for example Weyl group actions, and thus lots of the root systems arithmetic. Before: sage: W = WeylGroup(["A",5]) sage: %time l = list(W) CPU times: user 3.55 s, sys: 0.00 s, total: 3.55 s Wall time: 3.57 s After: sage: W = WeylGroup(["A",5]) sage: %time l = list(W) CPU times: user 2.80 s, sys: 0.00 s, total: 2.81 s Wall time: 2.81 s Please review! Cheers, Nicolas -- Nicolas M. Thiéry "Isil" <nthi...@users.sf.net> http://Nicolas.Thiery.name/ -- 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-devel@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.
