#14058: Weakly reference binary operation codomains
-------------------------------------+-------------------------------------
Reporter: robertwb | Owner: rlm
Type: enhancement | Status: needs_review
Priority: major | Milestone: sage-6.4
Component: memleak | Resolution:
Keywords: | Merged in:
Authors: Robert Bradshaw, | Reviewers: Simon King
Nils Bruin | Work issues:
Report Upstream: N/A | Commit:
Branch: | 9793dbc9bc64bfdce43ff1e626453816c302696d
u/SimonKing/weakly_reference_binary_operation_codomains| Stopgaps:
Dependencies: #12313 |
-------------------------------------+-------------------------------------
Comment (by pbruin):
Replying to [comment:45 SimonKing]:
> Sometimes, the following test in sage/categories/fields.py has failed:
> {{{
> sage: import gc
> sage: _ = gc.collect()
> sage: n = len([X for X in gc.get_objects() if isinstance(X,
sage.rings.finite_rings.integer_mod_ring.IntegerModRing_generic)])
> sage: for i in prime_range(100):
> ....: R = ZZ.quotient(i)
> ....: t = R in Fields()
> sage: _ = gc.collect()
> sage: len([X for X in gc.get_objects() if isinstance(X,
sage.rings.finite_rings.integer_mod_ring.IntegerModRing_generic)]) - n
> 1
> }}}
> The reason for the failure: Sometimes the last line gave 0, not 1. It is
not totally clear to me why the different results occurred. But in fact 0
is better than 1 here (one additional ring got collected).
Shouldn't the result always be 1 given that `R` refers to `Zmod(97)` after
the loop (unless there is a surviving reference from a `Zmod(97)` created
in some earlier test)? What happens if you do `del R` before the last
`gc.collect()`?
--
Ticket URL: <http://trac.sagemath.org/ticket/14058#comment:47>
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 http://groups.google.com/group/sage-trac.
For more options, visit https://groups.google.com/d/optout.
