在数据框中按日期索引过滤行

Question

我期待按日期过滤以下df,期待在索引值中仅按星期三过滤:

begin=2015-05-14
end=2015-05-22

Date
2015-05-14   81.370003  6.11282  39.753  44.950001
2015-05-15   80.419998  6.03380  39.289  44.750000
2015-05-18   80.879997  6.00746  41.249  44.360001
2015-05-19   80.629997  6.10465  41.047  40.980000
2015-05-20   80.550003  6.14370  41.636  42.790001
2015-05-21   80.480003  6.16096  42.137  43.680000
2015-05-22   80.540001  6.13916  42.179  43.490002

并继续..

这是我尝试过的:

df1=df[df.index.dayofweek == 2]

然后尝试:

df.index = pd.date_range(begin,end,freq='W')

两种情况都没有成功

期望的输出是相同的df,只返回星期四的行.

Answer 1

你可以先看过滤:

df = df.loc[begin:end]
df1=df[df.index.dayofweek == 2]
print (df1)
                    a       b       c          d
2015-05-20  80.550003  6.1437  41.636  42.790001