On Tue, Jan 13, 2009 at 4:17 AM, Martin Albrecht <m...@informatik.uni-bremen.de> wrote: > > Hi there, > > this is a continuation of a thread on [sage-nt] on arithmetic over Z/nZ[x] for > n word sized. > > http://groups.google.com/group/sage-nt/browse_thread/thread/6e415c61089ea435 > > It started about #4965 > > http://trac.sagemath.org/sage_trac/ticket/4965 > > as a call for help because I can't seem to find the cause of a bug in my > zmod_poly_t wrapper. The files that fail are: > > sage/schemes/hyperelliptic_curves/hyperelliptic_padic_field.py > sage/schemes/elliptic_curves/ell_number_field.py > > and details on the failure are given in the ticket. > > Later the thread moved on to discuss zn_poly and FLINT's zmod_poly_t. > > Craig asked how zmod_poly_t compares against zn_poly. I now added a function > _mul_zn_poly to the zmod_poly_t wrapper which exploits that -- for no -- the > internal formats of zn_poly and zmod_poly_t are very similar. > > The following is multiplication of two random polynomials over > GF(140737488355328) of length n > > n FLINT zn_poly > 512 0.000 0.001 > 1024 0.001 0.000 > 2048 0.002 0.002 > 4096 0.005 0.005 > 8192 0.011 0.012 > 16384 0.024 0.024 > 32768 0.051 0.053 > 65536 0.115 0.106 > 131072 0.292 0.220 > 262144 0.612 0.454 > 524288 1.522 1.028 > 1048576 3.136 2.096 > > Note, that the old Sage class is very slow compared to any of those > implementations: > > == Old Sage ZZ_pX wrapper == > > sage: P.<x> = PolynomialRing(GF(7)) > sage: type(x) > <type > 'sage.rings.polynomial.polynomial_modn_dense_ntl.Polynomial_dense_mod_p'> > sage: f = P.random_element(100) > sage: g = P.random_element(100) > sage: %timeit f*g > 1000 loops, best of 3: 445 µs per loop > > == New Sage FLINT wrapper == > sage: P.<x> = PolynomialRing(GF(7)) > sage: type(x) > <type 'sage.rings.polynomial.polynomial_zmod_flint.Polynomial_zmod_flint'> > sage: f = P.random_element(100) > sage: g = P.random_element(100) > sage: %timeit f*g > 100000 loops, best of 3: 7.92 µs per loop > > However, since there are still doctest failures I can't figure out, the patch > is just sitting on Trac (hint hint :))
Can't you write some code to automatically tell you what function in the new wrapper you wrote is working differently than in the old one? Obviously this would be a little tedious, but it seems to me that it would be completely straightforward to write, and far less work than all the work you have already put into this. In particular the class cdef class Polynomial_zmod_flint(Polynomial_template): only has like 5 or 6 methods. Just make a version of this class that is cdef class Polynomial_zmod_flint_and_ntl(Polynomial_template): say that defines versions of all 5 or 6 methods that use both ntl (or any solid known code) and flint in parallel, and checks that each function does the same thing. Then run it, and when it bombs you'll see exactly what type your made in the flint wrapping or bug there is in flint (or ntl). -- William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
