[igraph] assortativity for small world graph

[simone gabbriellini]

Hello,

I generate small world graph in python like this:

gSW = Graph.Lattice([1,g.vcount()], nei=sum(g.degree())/g.vcount(),  
directed=True, mutual=False);
gSW.rewire(int(0.05 * gSW.ecount()));
gSW.simplify(multiple=True, loops=True);
        
then I try to run the assortativity function as stated here:

http://igraph.wikidot.com/python-recipes

but what I got is an error:

ZeroDivisionError: float division

It seems that den1 and num2 are equal...

did someone experience the same problem?

many thanks,
Simone