is_tree¶
- is_tree(G)[source]¶
Returns True if
G
is a tree.A tree is a connected graph with no undirected cycles.
For directed graphs,
G
is a tree if the underlying graph is a tree. The underlying graph is obtained by treating each directed edge as a single undirected edge in a multigraph.- Parameters
- Ggraph
The graph to test.
- Returns
- bbool
A boolean that is True if
G
is a tree.
See also
Notes
In another convention, a directed tree is known as a polytree and then tree corresponds to an arborescence.