gistfile1.txt

def reciprocity(D):
        G=D.to_undirected() # copy
        for (u,v) in D.edges():
            if not D.has_edge(v,u):
                    G.remove_edge(u,v)
        return float(len(G.edges()))/len(D.to_undirected().edges())

# A simple test:

G = nx.DiGraph()
G.add_nodes_from([1,2,3])
G.add_edges_from([(1,2),(2,1),(2,3)])
reciprocity(G)
0.5