Ask Your Question
1

Constructing graphs using permutation or symmetric groups

asked 2019-05-04 22:47:42 +0100

homiermorphism gravatar image

updated 2019-08-29 18:19:40 +0100

FrédéricC gravatar image

I'm trying to construct a graph whose vertices are the elements of a permutation group or a symmetric group. Whenever I do this, it ignores the identity element (). For instance, when I use the Symmetric Group S3, it prints a graph with 5 vertices and the missing vertex is the identity.

Any ideas on why this happening and how I can fix it?

edit retag flag offensive close merge delete

Comments

Welcome to Ask Sage! Thank you for your question.

slelievre gravatar imageslelievre ( 2019-05-05 11:18:02 +0100 )edit
1

Please provide some code to let others reproduce the problem easily.

This dramatically increases the chances of an answer, the speed of getting an answer, and the accuracy with which the answers target the problem.

slelievre gravatar imageslelievre ( 2019-05-05 11:18:52 +0100 )edit

1 Answer

Sort by » oldest newest most voted
1

answered 2019-05-05 11:27:55 +0100

slelievre gravatar image

Using the Graph([list_of_vertices, list_of_edges]) construction, one can build a graph with vertices the elements in the symmetric group $S_3$, and with no edges, as follows:

sage: S = SymmetricGroup(3)
sage: G = Graph([list(S), []])
sage: G
Graph on 6 vertices

Not a very interesting graph... If the goal is a Cayley graph, use the dedicated method:

sage: C = S.cayley_graph()
sage: C
Digraph on 6 vertices

Tested with SageMath 8.8.beta4 built for Python 3.

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

Stats

Asked: 2019-05-04 22:47:42 +0100

Seen: 470 times

Last updated: May 05 '19