求助各位大神 我在进行这个策略编程时卡到5日线上穿10日线标记为金叉点 老出现错误~~翻了好多pdf未果，求大神赐教

import tushare as ts
import numpy as np
import pandas as pd

data=pd.DataFrame()
data = ts.get_hist_data('510050',start='2005-02-23',end='2016-07-28')
data.to_excel('c:/users/four/desktop/data.xls')
data1=pd.read_excel('c:/users/four/desktop/data.xls')

data2=pd.DataFrame()
data2['close']=data1['close']
data2['date']=data1['date']
data2['ma5']=pd.rolling_mean(data1['close'],5)
data2['ma10']=pd.rolling_mean(data1['close'],10)
data2['flag']=0

for i in range(4):
    data2['ma5']=np.mean(data1['close'][:i+1])

for k in range(9):
    data2['ma10'][k]=np.mean(data1['close'][:k+1])

for j in range(len(data2.index)):  
    if data2['ma5'][j] < data2['ma10'][j]:
        if data2['ma5'][j+1] > data2['ma10'][j+1]:
            if data2['flag'] == 0:
                data2['flag']=1



这是错误代码：
Traceback (most recent call last):

  File "<ipython-input-175-7f37a09b44b9>", line 4, in <module>
    if data2['flag'] == 0:

  File "D:\anaconda\lib\site-packages\pandas\core\generic.py", line 892, in __nonzero__
    .format(self.__class__.__name__))

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().