#14655: Dynkin diagrams does not copy like digraph
-----------------------------+----------------------------------------------
Reporter: tscrim | Owner: sage-combinat
Type: defect | Status: new
Priority: major | Milestone: sage-5.10
Component: combinatorics | Keywords: dynkin diagram copy
Work issues: | Report Upstream: N/A
Reviewers: | Authors:
Merged in: | Dependencies:
Stopgaps: |
-----------------------------+----------------------------------------------
Initializing:
{{{
sage: d = DynkinDiagram(['B',3,1])
sage: g = DiGraph()
sage: for x in d.vertices(): g.add_vertex(x)
sage: for y in d.edges(): g.add_edge(y)
sage: cd = copy(d)
sage: cg = copy(g)
sage: cd is d
False
sage: cd == d and cg == g
True
}}}
Now the correct behavior using `DiGraph`:
{{{
sage: g.vertices()
[0, 1, 2, 3]
sage: cg.vertices()
[0, 1, 2, 3]
sage: cg.add_vertex(4)
sage: g.vertices()
[0, 1, 2, 3]
sage: cg.vertices()
[0, 1, 2, 3, 4]
}}}
The error with `DynkinDiagram`:
{{{
sage: d.vertices()
[0, 1, 2, 3]
sage: cd.vertices()
[0, 1, 2, 3]
sage: cd.add_vertex(4)
sage: cd.vertices()
[0, 1, 2, 3, 4]
sage: d.vertices()
[0, 1, 2, 3, 4]
}}}
This causes problems with `automorphism_group(edge_labels=True)` noticed
by Mark Shimozono.
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/14655>
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?hl=en.
For more options, visit https://groups.google.com/groups/opt_out.
