def _initialize_preprocessing_tools(self, tokenize, stemmer, excluded_words, is_valid_word):
if stemmer:
self.stemmer = stemmer
else:
self.stemmer = LancasterStemmer()
if excluded_words:
self.excluded_words = set(stem_all(excluded_words, self.stemmer))
else:
self.excluded_words = set(stem_all(stopwords.words("english"), self.stemmer))
if is_valid_word is None:
self.is_valid_word = lambda word: (len(word) > 2) and (word not in self.excluded_words)
else:
self.is_valid_word = is_valid_word
if tokenize is None:
self.tokenize = word_tokenize
else:
self.tokenize = tokenize
def _split_text(self, text):
words = self.tokenize(text)
words = [word.rstrip('.') for word in words]
words = stem_all(words, self.stemmer)
return words