# <markdowncell>
# Note that the tags are a little bit different from the last parser we were using:
# <codecell>
quicktree("Melbourne has been transformed over the let 18 months in preparation for the visitors")
# <markdowncell>
# Neither parse is perfect, but the one we just generated has a major flaw: *Melbourne* is parsed as an adverb! Stanford CoreNLP correctly identifies it as a proper noun, and also, did a better job of handling the 'let' mistake.
# <markdowncell>
# *searchtree()* is a tiny function that searches a syntax tree. We'll use the sample sentence and *searchtree()* to practice our Tregex queries. We can feed it either *tags* (S, NP, VBZ, DT, etc.) or *tokens* enclosed in forward slashes.
# <codecell>
# any plural noun
query = r'NNS'
searchtree(melbtree, query)
# <codecell>
# A token matching the regex *Melb.?\**
query = r'/Melb.?/'
searchtree(melbtree, query)
# <codecell>
query = r'NP'
searchtree(melbtree, query)
# <markdowncell>
# To make things more specific, we can create queries with multiple criteria to match, and specify the relationship between each criterion we want to match. Tregex will print everything matching **the leftmost criterion**.
# <codecell>
# NP with 18 as a descendent
# <markdowncell>
# There are a number of different parsers, with some better than others:
# <codecell>
quicktree("Melbourne has been transformed over the let 18 months in preparation for the visitors")
# <markdowncell>
# Neither parse is perfect, but the one we just generated has a major flaw: *Melbourne* is parsed as an adverb! Stanford CoreNLP correctly identifies it as a proper noun, and also, did a better job of handling the 'let' mistake.
# <markdowncell>
# *searchtree()* is a tiny function that searches a syntax tree. We'll use the sample sentence and *searchtree()* to practice our Tregex queries. We can feed it either *tags* (S, NP, VBZ, DT, etc.) or *tokens* enclosed in forward slashes.
# <codecell>
# any plural noun
query = r'NNS'
searchtree(melbtree, query)
# <markdowncell>
# Here's some more documentation about Tregex queries:
# <codecell>
HTML('<iframe src=http://nlp.stanford.edu/~manning/courses/ling289/Tregex.html width=700 height=350></iframe>')
# <codecell>
#,,,
# <codecell>
#,,,
# <codecell>
#,,,
