spaCy/spacy/lang/ca/syntax_iterators.py

50 lines
1.9 KiB
Python

from typing import Iterator, Tuple, Union
from ...errors import Errors
from ...symbols import NOUN, PROPN
from ...tokens import Doc, Span
def noun_chunks(doclike: Union[Doc, Span]) -> Iterator[Tuple[int, int, int]]:
"""Detect base noun phrases from a dependency parse. Works on Doc and Span."""
# fmt: off
labels = ["nsubj", "nsubj:pass", "obj", "obl", "iobj", "ROOT", "appos", "nmod", "nmod:poss"]
# fmt: on
doc = doclike.doc # Ensure works on both Doc and Span.
if not doc.has_annotation("DEP"):
raise ValueError(Errors.E029)
np_deps = [doc.vocab.strings[label] for label in labels]
np_label = doc.vocab.strings.add("NP")
prev_end = -1
for i, word in enumerate(doclike):
if word.pos not in (NOUN, PROPN):
continue
# Prevent nested chunks from being produced
if word.left_edge.i <= prev_end:
continue
if word.dep in np_deps:
left = word.left_edge.i
right = word.right_edge.i + 1
# leave prepositions and punctuation out of the left side of the chunk
if word.left_edge.pos_ == "ADP" or word.left_edge.pos_ == "PUNCT":
left = word.left_edge.i + 1
prev_end = word.right_edge.i
# leave subordinated clauses and appositions out of the chunk
a = word.i + 1
while a < word.right_edge.i:
paraula = doc[a]
if paraula.pos_ == "VERB":
right = paraula.left_edge.i
prev_end = paraula.left_edge.i - 1
elif paraula.dep_ == "appos":
right = paraula.left_edge.i + 1
prev_end = paraula.left_edge.i - 1
a += 1
# leave punctuation out of the right side of the chunk
if word.right_edge.pos_ == "PUNCT":
right = right - 1
yield left, right, np_label
SYNTAX_ITERATORS = {"noun_chunks": noun_chunks}