Hello everybody !!!
I was looking at patch http://trac.sagemath.org/sage_trac/ticket/7184 when I
read again the usual lines :
n = G.vertices()[G.order()-1] + 1
G.add_vertex(n)
This, because the author wants to add a vertex to the graph, and this can
only be done by knowing the name of the vertex, which is 'n' in this case.
If one tries to add a vertex without knowing its name, the name chosen by
Sage is the first integer which is not already a vertex, and the user has no
way to know which one...
Is there any good reason why the function g.add_vertex does not return the
name of the newly created vertex ?
Besides, I can read this in the manual :
As it is implemented now, if a graph `G` has a large number
of vertices with numeric labels, then G.add_vertex() could
potentially be slow, if name is None
What is meant by "slow" ? Why should looking for the smallest integer not in
the graph be "slow" ?
Thank you !
Nathann
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