networkx.DiGraph.add_edge¶

DiGraph.
add_edge
(u_of_edge, v_of_edge, **attr)[source]¶ Add an edge between u and v.
The nodes u and v will be automatically added if they are not already in the graph.
Edge attributes can be specified with keywords or by directly accessing the edge’s attribute dictionary. See examples below.
Parameters:  u, v (nodes) – Nodes can be, for example, strings or numbers. Nodes must be hashable (and not None) Python objects.
 attr (keyword arguments, optional) – Edge data (or labels or objects) can be assigned using keyword arguments.
See also
add_edges_from()
 add a collection of edges
Notes
Adding an edge that already exists updates the edge data.
Many NetworkX algorithms designed for weighted graphs use an edge attribute (by default
weight
) to hold a numerical value.Examples
The following all add the edge e=(1, 2) to graph G:
>>> G = nx.Graph() # or DiGraph, MultiGraph, MultiDiGraph, etc >>> e = (1, 2) >>> G.add_edge(1, 2) # explicit twonode form >>> G.add_edge(*e) # single edge as tuple of two nodes >>> G.add_edges_from( [(1, 2)] ) # add edges from iterable container
Associate data to edges using keywords:
>>> G.add_edge(1, 2, weight=3) >>> G.add_edge(1, 3, weight=7, capacity=15, length=342.7)
For nonstring attribute keys, use subscript notation.
>>> G.add_edge(1, 2) >>> G[1][2].update({0: 5}) >>> G.edges[1, 2].update({0: 5})