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Implement the generate() method for NLTK's probabilistic context-free grammar to probabilistically generate valid sentences. (NLTK stands for Natural Language Toolkit.)
pip install pcfgRead the latest documentation for pcfg here.
A PCFG can be initialized in the same way that an NLTK probabilistic context-free grammar is initialized:
>>> from pcfg import PCFG
>>> grammar = PCFG.fromstring("""
S -> Subject Action [1.0]
Subject -> "a cow" [0.7] | "some guy" [0.1] | "the woman" [0.2]
Action -> "eats lunch" [0.5] | "was here" [0.5]
""")To generate sentences, simply use the generate() method:
>>> for sentence in grammar.generate(3):
... print(sentence)The output could be the following:
the woman eats lunch
the woman was here
a cow was here
Of course, your output may be different because the sentences are generated probabilistically.