Warning

This documents an unmaintained version of NetworkX. Please upgrade to a maintained version and see the current NetworkX documentation.

networkx.classes.function.is_weighted

is_weighted(G, edge=None, weight='weight')[source]

Returns True if G has weighted edges.

Parameters:
  • G (graph) – A NetworkX graph.
  • edge (tuple, optional) – A 2-tuple specifying the only edge in G that will be tested. If None, then every edge in G is tested.
  • weight (string, optional) – The attribute name used to query for edge weights.
Returns:

A boolean signifying if G, or the specified edge, is weighted.
Return type:

bool
Raises:

NetworkXError – If the specified edge does not exist.

Examples

>>> G = nx.path_graph(4)
>>> nx.is_weighted(G)
False
>>> nx.is_weighted(G, (2, 3))
False

>>> G = nx.DiGraph()
>>> G.add_edge(1, 2, weight=1)
>>> nx.is_weighted(G)
True