52 lines
1.4 KiB
Python
52 lines
1.4 KiB
Python
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# Natural Language Toolkit: WordNet stemmer interface
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#
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# Copyright (C) 2001-2018 NLTK Project
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# Author: Steven Bird <stevenbird1@gmail.com>
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# Edward Loper <edloper@gmail.com>
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# URL: <http://nltk.org/>
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# For license information, see LICENSE.TXT
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from __future__ import unicode_literals
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from nltk.corpus.reader.wordnet import NOUN
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from nltk.corpus import wordnet
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from nltk.compat import python_2_unicode_compatible
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@python_2_unicode_compatible
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class WordNetLemmatizer(object):
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"""
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WordNet Lemmatizer
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Lemmatize using WordNet's built-in morphy function.
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Returns the input word unchanged if it cannot be found in WordNet.
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>>> from nltk.stem import WordNetLemmatizer
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>>> wnl = WordNetLemmatizer()
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>>> print(wnl.lemmatize('dogs'))
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dog
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>>> print(wnl.lemmatize('churches'))
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church
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>>> print(wnl.lemmatize('aardwolves'))
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aardwolf
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>>> print(wnl.lemmatize('abaci'))
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abacus
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>>> print(wnl.lemmatize('hardrock'))
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hardrock
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"""
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def __init__(self):
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pass
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def lemmatize(self, word, pos=NOUN):
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lemmas = wordnet._morphy(word, pos)
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return min(lemmas, key=len) if lemmas else word
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def __repr__(self):
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return '<WordNetLemmatizer>'
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# unload wordnet
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def teardown_module(module=None):
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from nltk.corpus import wordnet
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wordnet._unload()
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