mirror of
https://github.com/explosion/spaCy.git
synced 2024-09-21 19:39:13 +03:00
70 lines
2.2 KiB
Python
70 lines
2.2 KiB
Python
from typing import Union, Iterator, Optional, List, Tuple
|
|
|
|
from ...symbols import NOUN, PROPN, PRON, VERB, AUX
|
|
from ...errors import Errors
|
|
from ...tokens import Doc, Span, Token
|
|
|
|
|
|
def noun_chunks(doclike: Union[Doc, Span]) -> Iterator[Span]:
|
|
"""Detect base noun phrases from a dependency parse. Works on Doc and Span."""
|
|
doc = doclike.doc
|
|
if not doc.is_parsed:
|
|
raise ValueError(Errors.E029)
|
|
if not len(doc):
|
|
return
|
|
np_label = doc.vocab.strings.add("NP")
|
|
left_labels = ["det", "fixed", "neg"] # ['nunmod', 'det', 'appos', 'fixed']
|
|
right_labels = ["flat", "fixed", "compound", "neg"]
|
|
stop_labels = ["punct"]
|
|
np_left_deps = [doc.vocab.strings.add(label) for label in left_labels]
|
|
np_right_deps = [doc.vocab.strings.add(label) for label in right_labels]
|
|
stop_deps = [doc.vocab.strings.add(label) for label in stop_labels]
|
|
token = doc[0]
|
|
while token and token.i < len(doclike):
|
|
if token.pos in [PROPN, NOUN, PRON]:
|
|
left, right = noun_bounds(
|
|
doc, token, np_left_deps, np_right_deps, stop_deps
|
|
)
|
|
yield left.i, right.i + 1, np_label
|
|
token = right
|
|
token = next_token(token)
|
|
|
|
|
|
def is_verb_token(token: Token) -> bool:
|
|
return token.pos in [VERB, AUX]
|
|
|
|
|
|
def next_token(token: Token) -> Optional[Token]:
|
|
try:
|
|
return token.nbor()
|
|
except IndexError:
|
|
return None
|
|
|
|
|
|
def noun_bounds(
|
|
doc: Doc,
|
|
root: Token,
|
|
np_left_deps: List[str],
|
|
np_right_deps: List[str],
|
|
stop_deps: List[str],
|
|
) -> Tuple[Token, Token]:
|
|
left_bound = root
|
|
for token in reversed(list(root.lefts)):
|
|
if token.dep in np_left_deps:
|
|
left_bound = token
|
|
right_bound = root
|
|
for token in root.rights:
|
|
if token.dep in np_right_deps:
|
|
left, right = noun_bounds(
|
|
doc, token, np_left_deps, np_right_deps, stop_deps
|
|
)
|
|
filter_func = lambda t: is_verb_token(t) or t.dep in stop_deps
|
|
if list(filter(filter_func, doc[left_bound.i : right.i],)):
|
|
break
|
|
else:
|
|
right_bound = right
|
|
return left_bound, right_bound
|
|
|
|
|
|
SYNTAX_ITERATORS = {"noun_chunks": noun_chunks}
|