spaCy/spacy/lemmatizer.py
ines 1da29a7146 Use new Lemmatizer data and remove file import
Since there's currently only an English lemmatizer, the global
Lemmatizer imports from spacy.en. This is unideal and still needs to be
fixed.
2017-03-12 13:58:22 +01:00

81 lines
2.6 KiB
Python

from __future__ import unicode_literals, print_function
import codecs
import pathlib
import ujson as json
from .en.lemmatizer import INDEX, EXC, RULES
from .symbols import POS, NOUN, VERB, ADJ, PUNCT
class Lemmatizer(object):
@classmethod
def load(cls, path, rules=None):
index = dict(INDEX)
exc = dict(EXC)
rules = dict(RULES)
return cls(index, exc, rules)
def __init__(self, index, exceptions, rules):
self.index = index
self.exc = exceptions
self.rules = rules
def __call__(self, string, univ_pos, morphology=None):
if univ_pos == NOUN:
univ_pos = 'noun'
elif univ_pos == VERB:
univ_pos = 'verb'
elif univ_pos == ADJ:
univ_pos = 'adj'
elif univ_pos == PUNCT:
univ_pos = 'punct'
# See Issue #435 for example of where this logic is requied.
if self.is_base_form(univ_pos, morphology):
return set([string.lower()])
lemmas = lemmatize(string, self.index.get(univ_pos, {}),
self.exc.get(univ_pos, {}),
self.rules.get(univ_pos, []))
return lemmas
def is_base_form(self, univ_pos, morphology=None):
'''Check whether we're dealing with an uninflected paradigm, so we can
avoid lemmatization entirely.'''
morphology = {} if morphology is None else morphology
others = [key for key in morphology if key not in (POS, 'number', 'pos', 'verbform')]
if univ_pos == 'noun' and morphology.get('number') == 'sing' and not others:
return True
elif univ_pos == 'verb' and morphology.get('verbform') == 'inf' and not others:
return True
else:
return False
def noun(self, string, morphology=None):
return self(string, 'noun', morphology)
def verb(self, string, morphology=None):
return self(string, 'verb', morphology)
def adj(self, string, morphology=None):
return self(string, 'adj', morphology)
def punct(self, string, morphology=None):
return self(string, 'punct', morphology)
def lemmatize(string, index, exceptions, rules):
string = string.lower()
forms = []
# TODO: Is this correct? See discussion in Issue #435.
#if string in index:
# forms.append(string)
forms.extend(exceptions.get(string, []))
for old, new in rules:
if string.endswith(old):
form = string[:len(string) - len(old)] + new
if form in index or not form.isalpha():
forms.append(form)
if not forms:
forms.append(string)
return set(forms)