#15278: Hash and equality for graphs
-------------------------------------+-------------------------------------
Reporter: SimonKing | Owner:
Type: defect | Status: needs_work
Priority: major | Milestone: sage-6.1
Component: graph theory | Resolution:
Keywords: | Merged in:
Authors: Simon King | Reviewers: Nathann Cohen
Report Upstream: N/A | Work issues:
Branch: | Commit:
u/SimonKing/ticket/15278 | 51d63284da70ffa4772a0d0fda6020750aef2e6d
Dependencies: #12601, #15491 | Stopgaps:
-------------------------------------+-------------------------------------
Comment (by SimonKing):
Ahaaa! By using `trace()`, I found that the above uses `__copy__`---and I
did change it. More precisely: It copies the "Hasse diagram of a poset
containing 4 elements", which has the `._immutable` flag set to true, but
the `sage.graphs.base.sparse_graph.SparseGraphBackend`.
So, the Hasse diagram is not truely immutable, but just pretends to be.
Either we should use the static sparse backend for Hasse diagrams, or we
should test the type of the backend, rather than only relying on the
`._immutable` flag (this is one of the things that I have suggested above,
and perhaps we should implement it).
--
Ticket URL: <http://trac.sagemath.org/ticket/15278#comment:65>
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/groups/opt_out.
