This method returns the nodes of the forest.
Value
A dataframe representing, for each node
in the forest, the identified (column cell_id),
whenever the node is not a root, the ancestor
identifier (column ancestor), whenever the
node was sampled, i.e., it is one of the forest
leaves, the name of the sample containing the
node, (column sample), the mutant (column
mutant), the epistate (column epistate),
and the birth time (column birth_time).
See also
SamplesForest$get_nodes() for usage examples