graphical_models.classes.dags.dag.DAG.sources

DAG.sources() → Set[Hashable]

Get all nodes in the graph that have no parents.

Returns

Nodes in the graph that have no parents.

Return type

List[node]

Example

>>> from graphical_models import DAG
>>> g = DAG(arcs={(1, 2), (1, 3), (2, 3)})
>>> g.sources()
{1}