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is_forest¶

is_forest
(G)[source]¶ Returns \(True\) if G is a forest.
A forest is a graph with no undirected cycles.
For directed graphs, \(G\) is a forest if the underlying graph is a forest. The underlying graph is obtained by treating each directed edge as a single undirected edge in a multigraph.
Parameters: G : graph
The graph to test.
Returns: b : bool
A boolean that is \(True\) if \(G\) is a forest.
See also
is_branching
Notes
In another convention, a directed forest is known as a polyforest and then forest corresponds to a branching.