nltk.Tree.productions¶

Tree.productions()[source]¶

Generate the productions that correspond to the non-terminal nodes of the tree. For each subtree of the form (P: C1 C2 ... Cn) this produces a production of the form P -> C1 C2 ... Cn.

>>> t = Tree.fromstring("(S (NP (D the) (N dog)) (VP (V chased) (NP (D the) (N cat))))")
>>> t.productions()
[S -> NP VP, NP -> D N, D -> 'the', N -> 'dog', VP -> V NP, V -> 'chased',
NP -> D N, D -> 'the', N -> 'cat']

Return type:	list(Production)