# networkx.algorithms.dag.dag_longest_path_length¶

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

Returns the longest path length in a DAG

Parameters
• G (NetworkX DiGraph) – A directed acyclic graph (DAG)

• weight (string, optional) – Edge data key to use for weight

• default_weight (int, optional) – The weight of edges that do not have a weight attribute

Returns

Longest path length

Return type

int

Raises

NetworkXNotImplemented – If G is not directed