def insertWebsite(self, url, domain):
		'''增加一个网页,标记为未访问,并对相应的domain增加其入度'''
		cur = self.conn.cursor()
		cur.execute("SELECT 1 FROM Domains WHERE domain=?", (domain,))
		result = cur.fetchone()
		if not result:
			# 未有对应domain记录, 先创建domain, 把入度设为1
			if VERBOSE:
				print 'Spot Domain:',domain
			self.insertDomain(domain, indegree=1)
			cur.execute("SELECT did FROM Domains WHERE domain=?", (domain,))
			did = cur.fetchone()[0]
		else:
			did = result[0]
			# 对应的domain记录已经存在, 对其入度+1
			cur.execute("UPDATE Domains SET outdegree=outdegree+1 WHERE domain=?", (domain,))

		cur.execute("INSERT INTO Websites VALUES (NULL,?,?,NULL,0)", (did, url,))
		# 写入到文件
		self.conn.commit()
def test_impl(nsyms):
            max_num_days = 100
            all_res = 0.0
            for i in sdc.prange(nsyms):
                s_open = 20 * np.ones(max_num_days)
                s_low = 28 * np.ones(max_num_days)
                s_close = 19 * np.ones(max_num_days)
                df = pd.DataFrame({'Open': s_open, 'Low': s_low, 'Close': s_close})
                df['Stdev'] = df['Close'].rolling(window=90).std()
                df['Moving Average'] = df['Close'].rolling(window=20).mean()
                df['Criteria1'] = (df['Open'] - df['Low'].shift(1)) < -df['Stdev']
                df['Criteria2'] = df['Open'] > df['Moving Average']
                df['BUY'] = df['Criteria1'] & df['Criteria2']
                df['Pct Change'] = (df['Close'] - df['Open']) / df['Open']
                df['Rets'] = df['Pct Change'][df['BUY']]
                all_res += df['Rets'].mean()
            return all_res