我有时间序列数据。我想为每个组创建序列，这样通过考虑一个月来组合7天。即每个组应在月内。
示例数据集
a
2017-09-25
2017-09-26
2017-09-27
2017-09-28
2017-09-29
2017-09-30
2017-10-01
2017-10-02
2017-10-03
2017-10-04
2017-10-05
2017-10-06
2017-10-07
2017-10-08
2017-10-09
2017-10-10
2017-10-11
2017-10-12
2017-10-13
2017-10-14
2017-10-15
2017-10-16
2017-10-17
2017-10-18
2017-10-19
2017-10-20
2017-10-21
2017-10-22
2017-10-23
2017-10-24
2017-10-25
2017-10-26
2017-10-27
2017-10-28
2017-10-29
2017-10-30
2017-10-31
2017-11-01
2017-11-02
2017-11-03
2017-11-04
2017-11-05
2017-11-06
2017-11-07
2017-11-08
2017-11-09
2017-11-10
2017-11-11
2017-11-12
2017-11-13
2017-11-14
2017-11-15
2017-11-16
2017-11-17
2017-11-18
2017-11-19
2017-11-20
2017-11-21
2017-11-22
2017-11-23
2017-11-24
2017-11-25
2017-11-26
2017-11-27
2017-11-28
2017-11-29
2017-11-30
预期产出：
a out
2017-09-25 0
2017-09-26 0
2017-09-27 0
2017-09-28 0
2017-09-29 0
2017-09-30 0
2017-10-01 1
2017-10-02 1
2017-10-03 1
2017-10-04 1
2017-10-05 1
2017-10-06 1
2017-10-07 1
2017-10-08 2
2017-10-09 2
2017-10-10 2
2017-10-11 2
2017-10-12 2
2017-10-13 2
2017-10-14 2
2017-10-15 3
2017-10-16 3
2017-10-17 3
2017-10-18 3
2017-10-19 3
2017-10-20 3
2017-10-21 3
2017-10-22 4
2017-10-23 4
2017-10-24 4
2017-10-25 4
2017-10-26 4
2017-10-27 4
2017-10-28 4
2017-10-29 5
2017-10-30 5
2017-10-31 5
2017-11-01 6
2017-11-02 6
2017-11-03 6
2017-11-04 6
2017-11-05 6
2017-11-06 6
2017-11-07 6
2017-11-08 7
2017-11-09 7
2017-11-10 7
2017-11-11 7
2017-11-12 7
2017-11-13 7
2017-11-14 7
2017-11-15 8
2017-11-16 8
2017-11-17 8
2017-11-18 8
2017-11-19 8
2017-11-20 8
2017-11-21 8
2017-11-22 9
2017-11-23 9
2017-11-24 9
2017-11-25 9
2017-11-26 9
2017-11-27 9
2017-11-28 9
2017-11-29 10
2017-11-30 10
到目前为止，我试过这个：
df['id_1']= df.groupby([pd.Grouper(freq='7D')]).ngroup()
df['id_2']= df.groupby([pd.Grouper(freq='W')]).ngroup()
df['id_3']= df.groupby([pd.Grouper(freq='7D'),pd.Grouper(freq='M')]).ngroup()
它给出了
a id_1 id_2 id_3
2017-09-25 0 0 0
2017-09-26 0 0 0
2017-09-27 0 0 0
2017-09-28 0 0 0
2017-09-29 0 0 0
2017-09-30 0 0 0
2017-10-01 0 0 1
2017-10-02 1 1 2
2017-10-03 1 1 2
2017-10-04 1 1 2
2017-10-05 1 1 2
2017-10-06 1 1 2
2017-10-07 1 1 2
2017-10-08 1 1 2
2017-10-09 2 2 3
2017-10-10 2 2 3
2017-10-11 2 2 3
2017-10-12 2 2 3
2017-10-13 2 2 3
2017-10-14 2 2 3
2017-10-15 2 2 3
2017-10-16 3 3 4
2017-10-17 3 3 4
2017-10-18 3 3 4
2017-10-19 3 3 4
2017-10-20 3 3 4
2017-10-21 3 3 4
2017-10-22 3 3 4
2017-10-23 4 4 5
2017-10-24 4 4 5
2017-10-25 4 4 5
2017-10-26 4 4 5
2017-10-27 4 4 5
2017-10-28 4 4 5
2017-10-29 4 4 5
2017-10-30 5 5 6
2017-10-31 5 5 6
2017-11-01 5 5 7
2017-11-02 5 5 7
2017-11-03 5 5 7
2017-11-04 5 5 7
2017-11-05 5 5 7
2017-11-06 6 6 8
2017-11-07 6 6 8
2017-11-08 6 6 8
2017-11-09 6 6 8
2017-11-10 6 6 8
2017-11-11 6 6 8
2017-11-12 6 6 8
2017-11-13 7 7 9
2017-11-14 7 7 9
2017-11-15 7 7 9
2017-11-16 7 7 9
2017-11-17 7 7 9
2017-11-18 7 7 9
2017-11-19 7 7 9
2017-11-20 8 8 10
2017-11-21 8 8 10
2017-11-22 8 8 10
2017-11-23 8 8 10
2017-11-24 8 8 10
2017-11-25 8 8 10
2017-11-26 8 8 10
2017-11-27 9 9 11
2017-11-28 9 9 11
2017-11-29 9 9 11
2017-11-30 9 9 11
请帮我摆脱这个。
随时提出问题。如果你没有理解这个问题。
答案 0 :(得分：2)
你可以GetMessage 2次：
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