#4968: implement fast linear algebra modulo n < 2^31
----------------------------------+-----------------------------------------
Reporter: malb | Owner: was
Type: enhancement | Status: needs_work
Priority: major | Milestone: sage-wishlist
Component: linear algebra | Resolution:
Keywords: | Work issues:
Report Upstream: N/A | Reviewers:
Authors: | Merged in:
Dependencies: #10281 | Stopgaps:
----------------------------------+-----------------------------------------
Comment (by malb):
Replying to [comment:18 mraum]:
> The unsigned long thing seems OK (int_fast64_t is a C type, defined in
stdint.h). For consistency it would be good if MAX_MODULUS was
INTEGER_MOD_INT64_LIMIT to be found in sage/rings/finite_rings/stdint.h
this is less by one. In integer_mod.pyx the modulus is tested using <= and
in the patch < is used.
You are right, I got confused about Cython ctypdefs. "unsigned long" does
not appear in a meaningful way in the generated C files. Sorry for the
noise. Still, the documentation is wrong in various places and should be
fixed (machine sized ints).
> Apart from this I more or less agree with all points made previously. If
you don't see a good reason to change the Strassen cutoff, I would leave
it at is. File a new ticket instead. We should optimize it, but changing
it based on one observation is daring.
Fair enough, so let's make more observations. This code is about
performance. I am not saying: let's run a comprehensive optimisation suite
but not at least trying to use cutoffs which make the code reasonable fast
seems wrong.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/4968#comment:19>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
