dag_longest_path_length#

dag_longest_path_length(G, weight='weight', default_weight=1)[source]#

Returns the longest path length in a DAG

Parameters:

GNetworkX DiGraph: A directed acyclic graph (DAG)
weightstring, optional: Edge data key to use for weight
default_weightint, optional: The weight of edges that do not have a weight attribute

Returns:

int: Longest path length

Raises:

NetworkXNotImplemented: If G is not directed

See also

dag_longest_path

Examples

>>> DG = nx.DiGraph(
...     [(0, 1, {"cost": 1}), (1, 2, {"cost": 1}), (0, 2, {"cost": 42})]
... )
>>> list(nx.all_simple_paths(DG, 0, 2))
[[0, 1, 2], [0, 2]]
>>> nx.dag_longest_path_length(DG)
2
>>> nx.dag_longest_path_length(DG, weight="cost")
42