class SearchEngine(object):
def __init__(self, mystem_path, documents, dictionary):
self._documents = documents
self._N = len(documents)
self._dictionary = dictionary
self._lemmer = Lemmer(mystem_path)
def _get_df(self, postings):
return len(set(postings))
def _get_top(self, scores):
result = []
sorted_scores = sorted(scores.items(), key=lambda (document_id, score): score)
for (document_id, score) in sorted_scores[-10:]:
path = self._documents[document_id]
result.append((path, score))
return result
def search(self, *args):
tfidf = defaultdict(dict)
query = [self._lemmer.translate(word) for word in args]
query_dictionary = dict((word, self._dictionary.get(word)) for word in query)
for (word, postings) in query_dictionary.iteritems():
df = self._get_df(postings)
idf = math.log(self._N / float(df))
for document_id in xrange(self._N):
tf = query_dictionary[word].count(document_id)
tfidf[word][document_id] = idf * tf
scores = {}
for document_id in xrange(self._N):
score = 0
for word in query:
score += tfidf[word][document_id]
scores[document_id] = score
pprint.pprint(self._get_top(scores))
if options.collection_dir is None:
parser.error('Collection directory option is required!')
if options.index_path is None:
parser.error('Index file is not specified!')
def walk(path):
for root_dir, dirs, files in os.walk(path):
for file in files:
yield os.path.join(root_dir, file)
dictionary = defaultdict(list)
documents = []
lemmer = Lemmer(options.mystem_path)
scanner = Scanner()
for (document_id, document_path) in enumerate(walk(options.collection_dir)):
with codecs.open(document_path, 'r', 'cp1251') as f:
words = scanner.scan(f.read())
for word in words:
if word:
stem = lemmer.translate(word)
dictionary[stem].append(document_id)
documents.append(document_path)
print '.',
items = dictionary.items()
items.sort(key=lambda (stem, postings): len(documents))
def __init__(self, mystem_path, documents, dictionary):
self._documents = documents
self._N = len(documents)
self._dictionary = dictionary
self._lemmer = Lemmer(mystem_path)
