#11935: Make parent/element classes independent of base rings
-----------------------------------------------------------------+----------
Reporter: SimonKing |
Owner: nthiery
Type: enhancement |
Status: needs_review
Priority: major |
Milestone: sage-5.0
Component: categories |
Resolution:
Keywords: parent class, element class, category | Work
issues:
Report Upstream: N/A |
Reviewers:
Authors: Simon King | Merged
in:
Dependencies: #9138, #11900, #11943, #12875, #12876, #12877 |
Stopgaps:
-----------------------------------------------------------------+----------
Comment (by SimonKing):
Replying to [comment:53 nthiery]:
> It indeed sounds a bit like a waste, to construct the parent class of
Algebras(GF(5)) to have to reconstruct all the hierarchy of super
categories above Algebras(GF(5)) (e.g. Modules(GF(5)), ...). With the
updated patch, Algebras(K).parent_class directly reuses
Algebras(L).parent_class if it already exists and if K and L have the same
category. The super_categories method of Algebras(K) is not even called.
I was thinking of that, too. But it would only work if we rely on the
assumption that the list of super_categories of a category with base
''only'' depends on the category of the base. Can we? Then, to the very
least, that assumption must be clearly stated somewhere.
> To achieve this, each subcategory of CategoryWithParameters should
provide a method _make_named_class_key specifying on what the parent_class
(and friends) depend on. For example, Category_over_base specifies that
parent_class depends only on the category of the base.
> Then, _make_named_class uses that to do a lookup in a cache.
>
> For our typical benchmark:
> {{{
> %time L = EllipticCurve('960d1').prove_BSD()
> }}}
> the time on my machine goes from 4s down to 3.5s. With the subcategory
patch, the times goes down from 7s to 3.75s. This makes the subcategory
patch acceptable.
I am a bit confused. What is the "subcategory patch"? Is it
"share_on_base_category"? And what patches are applied for the four
different timings?
> One fine point is that e.g. Algebras(ZZ) and Algebras(ZZ['x']) don't
share the same parent class anymore, since ZZ and ZZ['x'] don't have the
same category.
Sure, but I don't think that is necessarily bad.
> What do you think? Could you have a brief look at the experimental
trac11935_share_on_base_category.patch I just attached? If it sounds
reasonable to you, I'll finalize it (doctests, ...), and fold it in my
reviewer's patch.
I am currently running tests without it. But I am now reading it.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/11935#comment:55>
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.
