spaCy/spacy/lang/ru/lemmatizer.py
Adriane Boyd 3bcf74aca7 Rename and update ru pymorphy2 lookup lemmatize
* To allow default lookup lemmatization with a blank Russian model,
rename pymorphy2 lookup mode to `pymorphy2_lookup`

* Bug fix: update pymorphy2 lookup lemmatize to return list rather than
string
2021-03-15 11:11:06 +01:00

180 lines
6.0 KiB
Python

from typing import Optional, List, Dict, Tuple
from thinc.api import Model
from ...pipeline import Lemmatizer
from ...symbols import POS
from ...tokens import Token
from ...vocab import Vocab
PUNCT_RULES = {"«": '"', "»": '"'}
class RussianLemmatizer(Lemmatizer):
_morph = None
def __init__(
self,
vocab: Vocab,
model: Optional[Model],
name: str = "lemmatizer",
*,
mode: str = "pymorphy2",
overwrite: bool = False,
) -> None:
try:
from pymorphy2 import MorphAnalyzer
except ImportError:
raise ImportError(
"The Russian lemmatizer requires the pymorphy2 library: "
'try to fix it with "pip install pymorphy2"'
) from None
if RussianLemmatizer._morph is None:
RussianLemmatizer._morph = MorphAnalyzer()
super().__init__(vocab, model, name, mode=mode, overwrite=overwrite)
def pymorphy2_lemmatize(self, token: Token) -> List[str]:
string = token.text
univ_pos = token.pos_
morphology = token.morph.to_dict()
if univ_pos == "PUNCT":
return [PUNCT_RULES.get(string, string)]
if univ_pos not in ("ADJ", "DET", "NOUN", "NUM", "PRON", "PROPN", "VERB"):
# Skip unchangeable pos
return [string.lower()]
analyses = self._morph.parse(string)
filtered_analyses = []
for analysis in analyses:
if not analysis.is_known:
# Skip suggested parse variant for unknown word for pymorphy
continue
analysis_pos, _ = oc2ud(str(analysis.tag))
if analysis_pos == univ_pos or (
analysis_pos in ("NOUN", "PROPN") and univ_pos in ("NOUN", "PROPN")
):
filtered_analyses.append(analysis)
if not len(filtered_analyses):
return [string.lower()]
if morphology is None or (len(morphology) == 1 and POS in morphology):
return list(set([analysis.normal_form for analysis in filtered_analyses]))
if univ_pos in ("ADJ", "DET", "NOUN", "PROPN"):
features_to_compare = ["Case", "Number", "Gender"]
elif univ_pos == "NUM":
features_to_compare = ["Case", "Gender"]
elif univ_pos == "PRON":
features_to_compare = ["Case", "Number", "Gender", "Person"]
else: # VERB
features_to_compare = [
"Aspect",
"Gender",
"Mood",
"Number",
"Tense",
"VerbForm",
"Voice",
]
analyses, filtered_analyses = filtered_analyses, []
for analysis in analyses:
_, analysis_morph = oc2ud(str(analysis.tag))
for feature in features_to_compare:
if (
feature in morphology
and feature in analysis_morph
and morphology[feature].lower() != analysis_morph[feature].lower()
):
break
else:
filtered_analyses.append(analysis)
if not len(filtered_analyses):
return [string.lower()]
return list(set([analysis.normal_form for analysis in filtered_analyses]))
def pymorphy2_lookup_lemmatize(self, token: Token) -> List[str]:
string = token.text
analyses = self._morph.parse(string)
if len(analyses) == 1:
return [analyses[0].normal_form]
return [string]
def oc2ud(oc_tag: str) -> Tuple[str, Dict[str, str]]:
gram_map = {
"_POS": {
"ADJF": "ADJ",
"ADJS": "ADJ",
"ADVB": "ADV",
"Apro": "DET",
"COMP": "ADJ", # Can also be an ADV - unchangeable
"CONJ": "CCONJ", # Can also be a SCONJ - both unchangeable ones
"GRND": "VERB",
"INFN": "VERB",
"INTJ": "INTJ",
"NOUN": "NOUN",
"NPRO": "PRON",
"NUMR": "NUM",
"NUMB": "NUM",
"PNCT": "PUNCT",
"PRCL": "PART",
"PREP": "ADP",
"PRTF": "VERB",
"PRTS": "VERB",
"VERB": "VERB",
},
"Animacy": {"anim": "Anim", "inan": "Inan"},
"Aspect": {"impf": "Imp", "perf": "Perf"},
"Case": {
"ablt": "Ins",
"accs": "Acc",
"datv": "Dat",
"gen1": "Gen",
"gen2": "Gen",
"gent": "Gen",
"loc2": "Loc",
"loct": "Loc",
"nomn": "Nom",
"voct": "Voc",
},
"Degree": {"COMP": "Cmp", "Supr": "Sup"},
"Gender": {"femn": "Fem", "masc": "Masc", "neut": "Neut"},
"Mood": {"impr": "Imp", "indc": "Ind"},
"Number": {"plur": "Plur", "sing": "Sing"},
"NumForm": {"NUMB": "Digit"},
"Person": {"1per": "1", "2per": "2", "3per": "3", "excl": "2", "incl": "1"},
"Tense": {"futr": "Fut", "past": "Past", "pres": "Pres"},
"Variant": {"ADJS": "Brev", "PRTS": "Brev"},
"VerbForm": {
"GRND": "Conv",
"INFN": "Inf",
"PRTF": "Part",
"PRTS": "Part",
"VERB": "Fin",
},
"Voice": {"actv": "Act", "pssv": "Pass"},
"Abbr": {"Abbr": "Yes"},
}
pos = "X"
morphology = dict()
unmatched = set()
grams = oc_tag.replace(" ", ",").split(",")
for gram in grams:
match = False
for categ, gmap in sorted(gram_map.items()):
if gram in gmap:
match = True
if categ == "_POS":
pos = gmap[gram]
else:
morphology[categ] = gmap[gram]
if not match:
unmatched.add(gram)
while len(unmatched) > 0:
gram = unmatched.pop()
if gram in ("Name", "Patr", "Surn", "Geox", "Orgn"):
pos = "PROPN"
elif gram == "Auxt":
pos = "AUX"
elif gram == "Pltm":
morphology["Number"] = "Ptan"
return pos, morphology