Re: [igraph] how to add disconnected nodes to a graph?

[Tamás Nepusz]

> If I am computing the betweenness of a vertex that doesn't connect to any 
> other node. Shouldn't the betweenness be 0?

Yes, it should. It seems to be the case in a small example that I constructed 
now in IPython:

In [1]: g=Graph.Formula("A--B--C--D--A, E, F")
In [2]: g.betweenness()

Out[2]: [0.5, 0.5, 0.5, 0.5, 0.0, 0.0]

So if you are getting non-zero values for isolated nodes then this does not 
seem right.

T.