)
(VP
(VB gave)
(NP
(DT the)
(NN lecture)
)
)
)"""
# uncomment to use the above simple trees for debugging:
# trees = [TRANSFORM(Tree.from_string(t)) for t in (t0, t1)]
# grammar = PCFG.from_trees(trees)
# let's get some input to build a grammar:
grammar = PCFG.from_trees(list(TRANSFORM(t) for t in Tree.from_stream(GzipFile('bigger_treebank_2.txt.gz'))))
print "Read {} rules in grammar.".format(len(grammar))
trees = list(TRANSFORM(t) for t in Tree.from_stream(open('end_of_wsj.txt')))
print "Read {} trees.".format(len(trees))
# now try and parse our trees:
results = []
for idx, tree in enumerate(trees):
tokens = [(t,) for t in tree.terminals()]
# print 'Sentence {}\tTokens: "{}"'.format(idx, ' '.join(tree.terminals()))
chart = Chart(grammar, tokens)
chart.pretty_print()
has_parse = chart.extract_parse()
if not has_parse:
print 'Sentence {}\tTokens: "{}" has no parse!'.format(idx, ' '.join(tree.terminals()))
