def insertDomain(self, domain, indegree=0, outdegree=0):
		'''增加一个域名'''
		cur = self.conn.cursor()
		cur.execute("INSERT INTO Domains VALUES (NULL,?,?,?)", (domain, indegree, outdegree))
		# 写入到文件中
		self.conn.commit()
def __initialize_kmeans(self):
        initial_centers = kmeans_plusplus_initializer(self.__sample, self.__amount).initialize()
        kmeans_instance = kmeans(self.__sample, initial_centers, ccore = True)
        kmeans_instance.process()