numpy pandas 索引注意事项

pandas.DataFrame 的 iloc

 # ------------------------------------------------------------
 'python式的切片，包含为尾位置'
 In [23]:df = pd.DataFrame({
             'http_status': [200,200,404,404,301],
             'response_time': [0.04, 0.02, 0.07, 0.08, 1.0]},
             index=[0,1,2,3,4])

 In [26]:df[1:3]
 Out[26]:
    http_status  response_time
 1          200           0.02
 2          404           0.07

 In [24]:df.iloc[1:3,:]
 Out[24]:
    http_status  response_time
 1          200           0.02
 2          404           0.07

 In [28]:df.values[1:3,:]
 Out[28]:
 array([[  2.00000000e+02,   2.00000000e-02],
        [  4.04000000e+02,   7.00000000e-02]])

 # ------------------------------------------------------------
 'matlab式的切片，包含尾位置'
 In [29]:df.ix[1:3,:]
 Out[29]:
    http_status  response_time
 1          200           0.02
 2          404           0.07
 3          404           0.08