edge_boundary¶

edge_boundary
(G, nbunch1, nbunch2=None)[source]¶ Return the edge boundary.
Edge boundaries are edges that have only one end in the given set of nodes.
Parameters:  G (graph) – A networkx graph
 nbunch1 (list, container) – Interior node set
 nbunch2 (list, container) – Exterior node set. If None then it is set to all of the nodes in G not in nbunch1.
Returns: elist – List of edges
Return type: Notes
Nodes in nbunch1 and nbunch2 that are not in G are ignored.
nbunch1 and nbunch2 are usually meant to be disjoint, but in the interest of speed and generality, that is not required here.