#20445: Iteration through finite Coxeter groups
-------------------------+-------------------------------------------------
Reporter: | Owner:
stumpc5 | Status: new
Type: | Milestone: sage-7.2
enhancement | Resolution:
Priority: major | Merged in:
Component: | Reviewers:
combinatorics | Work issues:
Keywords: | Commit:
Authors: | abfff5ffdf5e3d7a90bdaa542ecca3ba2691bffe
Report Upstream: N/A | Stopgaps:
Branch: |
u/stumpc5/20445 |
Dependencies: |
-------------------------+-------------------------------------------------
Comment (by nthiery):
Replying to [comment:27 tscrim]:
> I'm really starting to consider that what we should do is create our own
separate project where we write all of this independently (in, say,
C/C++). At this stage, I'm somewhat concerned with the additional overhead
that Cython could impose and the lack of complete memory control. Although
I cannot commit serious time to working on this for then next two weeks (I
will be in grading and math mode). Over the summer starting in June, I
should be able to do so.
We can discuss this in Meudon.
> I think we can avoid a bit of overhead of maintaining the GAP and
category information. Although it is hard to tell how much of an impact
this will have on things.
For the record: I just checked, and the data structure for permutation
group elements is just a reference to the parent and a C-list of ints;
plus a few slots which are unused by default (e.g. a reference to a
gap element). So the only overhead is copying over the reference to
the parent, and a bit of extra memory allocation
Of course, the parent itself has stuff about GAP and categories, but
that's initialized once for all, and does not influence arithmetic on
elements.
Cheers,
Nicolas
--
Ticket URL: <http://trac.sagemath.org/ticket/20445#comment:29>
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 unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
