python - 新的 DataFrame 是每天的平均值

Question

    Site    Parameter   Date (LST)  Year    Month   Day Hour    Value   Unit    Duration    QC Name
1   Beijing PM2.5   2017-01-01 00:00:00 2017    1   1   0   505 µg/m_   1 Hr    Valid
2   Beijing PM2.5   2017-01-01 01:00:00 2017    1   1   1   485 µg/m_   1 Hr    Valid
3   Beijing PM2.5   2017-01-01 02:00:00 2017    1   1   2   466 µg/m_   1 Hr    Valid
4   Beijing PM2.5   2017-01-01 03:00:00 2017    1   1   3   435 µg/m_   1 Hr    Valid
5   Beijing PM2.5   2017-01-01 04:00:00 2017    1   1   4   405 µg/m_   1 Hr    Valid
6   Beijing PM2.5   2017-01-01 05:00:00 2017    1   1   5   402 µg/m_   1 Hr    Valid
7   Beijing PM2.5   2017-01-01 06:00:00 2017    1   1   6   407 µg/m_   1 Hr    Valid
8   Beijing PM2.5   2017-01-01 07:00:00 2017    1   1   7   435 µg/m_   1 Hr    Valid
9   Beijing PM2.5   2017-01-01 08:00:00 2017    1   1   8   472 µg/m_   1 Hr    Valid
10  Beijing PM2.5   2017-01-01 09:00:00 2017    1   1   9   465 µg/m_   1 Hr    Valid
11  Beijing PM2.5   2017-01-01 10:00:00 2017    1   1   10  473 µg/m_   1 Hr    Valid
12  Beijing PM2.5   2017-01-01 11:00:00 2017    1   1   11  456 µg/m_   1 Hr    Valid
13  Beijing PM2.5   2017-01-01 12:00:00 2017    1   1   12  474 µg/m_   1 Hr    Valid
14  Beijing PM2.5   2017-01-01 13:00:00 2017    1   1   13  510 µg/m_   1 Hr    Valid
15  Beijing PM2.5   2017-01-01 14:00:00 2017    1   1   14  596 µg/m_   1 Hr    Valid
16  Beijing PM2.5   2017-01-01 15:00:00 2017    1   1   15  580 µg/m_   1 Hr    Valid
17  Beijing PM2.5   2017-01-01 16:00:00 2017    1   1   16  556 µg/m_   1 Hr    Valid
18  Beijing PM2.5   2017-01-01 17:00:00 2017    1   1   17  522 µg/m_   1 Hr    Valid
19  Beijing PM2.5   2017-01-01 18:00:00 2017    1   1   18  495 µg/m_   1 Hr    Valid
20  Beijing PM2.5   2017-01-01 19:00:00 2017    1   1   19  500 µg/m_   1 Hr    Valid
21  Beijing PM2.5   2017-01-01 20:00:00 2017    1   1   20  484 µg/m_   1 Hr    Valid
22  Beijing PM2.5   2017-01-01 21:00:00 2017    1   1   21  452 µg/m_   1 Hr    Valid
23  Beijing PM2.5   2017-01-01 22:00:00 2017    1   1   22  427 µg/m_   1 Hr    Valid
24  Beijing PM2.5   2017-01-01 23:00:00 2017    1   1   23  444 µg/m_   1 Hr    Valid
25  Beijing PM2.5   2017-01-02 00:00:00 2017    1   2   0   428 µg/m_   1 Hr    Valid
26  Beijing PM2.5   2017-01-02 01:00:00 2017    1   2   1   466 µg/m_   1 Hr    Valid
27  Beijing PM2.5   2017-01-02 02:00:00 2017    1   2   2   452 µg/m_   1 Hr    Valid
28  Beijing PM2.5   2017-01-02 03:00:00 2017    1   2   3   442 µg/m_   1 Hr    Valid
29  Beijing PM2.5   2017-01-02 04:00:00 2017    1   2   4   390 µg/m_   1 Hr    Valid
30  Beijing PM2.5   2017-01-02 05:00:00 2017    1   2   5   317 µg/m_   1 Hr    Valid

如何从此处显示的(截断的)创建一个新的 DataFrame，该 DataFrame 显示了所有列，但不是显示逐小时的值，而是显示当天的平均值？

Answer 1

你可以尝试:

import datetime from datetime

df['Dates'] = df['Date (LST)'].dt.date

df['hour_average'] = df.groupby(['Dates'])['Hour'].transform('mean')