Hi
On 7 April 2018 at 14:52, Henri Girard <[email protected]> wrote:
> I made this graph (meaning a fano's plane) but I have the zero outside the
> graph ?
>
> I don't understand why ? someone could explain ?
>
> My adjacency_matrix is 8 but shouldn't be 7 ?
>
> g=Graph(7)
> edges = [(1,2), (1,3), (1,4),
> (2,3), (2,4), (2,5), (2, 6),
> (3,4), (3,5), (3,6), (3,7),
> (4,6), (4,7), (5,6), (6,7)]
> g.add_edge(1,2),g.add_edge(1,3),g.add_edge(1,4),g.add_edge(2,3),
> g.add_edge(2,4),g.add_edge(2,5),g.add_edge(2,6),g.add_edge(3,4),
> g.add_edge(3,5),g.add_edge(3,6),g.add_edge(3,7),g.add_edge(4,6),
> g.add_edge(4,7),g.add_edge(5,6),g.add_edge(6,7)
> g.show()
> g.adjacency_matrix(),g.incidence_matrix()
>
> Best
>
Graph? shows
2. "Graph(5)" -- return an edgeless graph on the 5 vertices
0,...,4.
3. "Graph([list_of_vertices,list_of_edges])" -- returns a
graph with given vertices/edges.
To bypass auto-detection, prefer the more explicit
"Graph([V,E],format='vertices_and_edges')".
4. "Graph(list_of_edges)" -- return a graph with a given list
of edges (see documentation of "add_edges()").
To bypass auto-detection, prefer the more explicit "Graph(L,
format='list_of_edges')".
5. "Graph({1:[2,3,4],3:[4]})" -- return a graph by
associating to each vertex the list of its neighbors.
To bypass auto-detection, prefer the more explicit "Graph(D,
format='dict_of_lists')".
so it seems correct, and there are alternatives if you prefer 1..8 instead
of 0..7.
Regards,
Jan
>
>
--
.~.
/V\ Jan Groenewald
/( )\ www.aims.ac.za
^^-^^
--
You received this message because you are subscribed to the Google Groups
"sage-support" 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 https://groups.google.com/group/sage-support.
For more options, visit https://groups.google.com/d/optout.
