Note
This documents the development version of NetworkX. Documentation for the current release can be found here.
networkx.algorithms.reciprocity.reciprocity¶

reciprocity
(G, nodes=None)[source]¶ Compute the reciprocity in a directed graph.
The reciprocity of a directed graph is defined as the ratio of the number of edges pointing in both directions to the total number of edges in the graph. Formally, \(r = {(u,v) \in G(v,u) \in G} / {(u,v) \in G}\).
The reciprocity of a single node u is defined similarly, it is the ratio of the number of edges in both directions to the total number of edges attached to node u.
 Parameters
 Ggraph
A networkx directed graph
 nodescontainer of nodes, optional (default=whole graph)
Compute reciprocity for nodes in this container.
 Returns
 outdictionary
Reciprocity keyed by node label.
Notes
The reciprocity is not defined for isolated nodes. In such cases this function will return None.