How to group a pandas dataframe by a defined time interval?

Question

I have a dataFrame like this, I would like to group every 60 minutes and start grouping at 06:30.

                           data
index
2017-02-14 06:29:57           


        

Answer 1

Using DataFrame.resample which is a dedicated method for resampling time series, this way we dont need DataFrame.GroupBy and pd.Grouper:

df.resample('60min', base=30, label='right').first()

Output

                           data
index                          
2017-02-14 06:30:00  11198648.0
2017-02-14 07:30:00  11198650.0
2017-02-14 08:30:00         NaN
2017-02-14 09:30:00         NaN
2017-02-14 10:30:00         NaN
2017-02-14 11:30:00         NaN
2017-02-14 12:30:00         NaN
2017-02-14 13:30:00         NaN
2017-02-14 14:30:00         NaN
2017-02-14 15:30:00         NaN
2017-02-14 16:30:00         NaN
2017-02-14 17:30:00         NaN
2017-02-14 18:30:00         NaN
2017-02-14 19:30:00         NaN
2017-02-14 20:30:00         NaN
2017-02-14 21:30:00         NaN
2017-02-14 22:30:00         NaN
2017-02-14 23:30:00  11207728.0

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Notice: when you have multiple columns in your dataframe, you have to specify the column you want to aggregate on:

df.resample('60min', base=30, label='right')['data'].first()