Warning

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

networkx.algorithms.components.is_semiconnected

is_semiconnected(G, topo_order=None)

Returns True if the graph is semiconnected, False otherwise.

A graph is semiconnected if, and only if, for any pair of nodes, either one is reachable from the other, or they are mutually reachable.

Parameters

• G (NetworkX graph) – A directed graph.

• topo_order (list or tuple, optional) – A topological order for G (if None, the function will compute one)

Returns

semiconnected – True if the graph is semiconnected, False otherwise.

Return type

bool

Raises

• NetworkXNotImplemented : – If the input graph is undirected.

• NetworkXPointlessConcept : – If the graph is empty.

Examples

>>> G=nx.path_graph(4,create_using=nx.DiGraph())
>>> print(nx.is_semiconnected(G))
True
>>> G=nx.DiGraph([(1, 2), (3, 2)])
>>> print(nx.is_semiconnected(G))
False

See also

is_strongly_connected(), is_weakly_connected(), is_connected(), is_biconnected()