edge_incident bug in generic_graph.py

[videlec]

Currently, the edge_incident method of generic graph calls edge_boundary which first take a lot of time and secondly does not work

sage: G = Graph(loops=True)
sage: G.add_edge(0,0)
sage: G.edges()
[(0, 0, None)]
sage: list(G.edge_iterator(0))
[(0, 0, None)]
sage: G.edges_incident(0)
[]

The ticket also aims to reduce multiple calls (edge_boundary does not call directly edge_iterator as it should).

It is also the occasion to add some doc and correct some typos.

Apply first :

• Complete rewrite of LP solver interfaces #10043
• is_line_graph() method #10101
• Hamiltonian cycles in undirected graphs - backtracking algorithm. #9698

CC: @nathanncohen

Component: graph theory

Author: Vincent Delecroix

Reviewer: Nathann Cohen

Merged: sage-4.6.1.alpha0

Issue created by migration from https://trac.sagemath.org/ticket/9581

[nathanncohen]

comment:2

Excellent ! Thank youuuuuuuuuuuuuu !!

Your patch is very nice, applies fine and everything.. I would just like to append a short line, because of a missing "if". If you agree with this, let's say this ticket is positively reviewed ! :-)

Nathann

[nathanncohen]

Attachment: trac_9581-fix.patch.gz

[videlec]

comment:3

Nathan, Why did you put this ticket as needs_review? It seems to be important to be a lot more explicit in the definition of each function of generic_graph and implement all the cases in examples... perhaps it is the matter of another ticket...

[nathanncohen]

comment:4

Hello ! Well, if you think it needs more documenation or tests, this ticket certainly is the one that should contain it... I thought the behaviour of these functions did not change that much, only "internal modifications", so... But I'm sorry for this, all you just said is better done here ! :-)

[videlec]

apply only this patch which takes care of Nathan remark

[videlec]

comment:5

Attachment: trac_9581-edge_incident.patch.gz

[nathanncohen]

comment:6

Hello !!! I can not apply this patch on 4.6.alpha3, looks like it needs to be rebased ^^;

Nathann

[videlec]

rebased version (apply only this one)

[videlec]

comment:7

Attachment: trac_9581-edge_incident.2.patch.gz

[nathanncohen]

comment:8

Positive review to this rebased version :-)

Nathann

[jdemeyer]

Reviewer: Nathann Cohen

[jdemeyer]

Changed author from vdelecroix to Vincent Delecroix

[jdemeyer]

Merged: sage-4.6.1.alpha0