itertuples, new column, datetime, pandas

[karlito]

Hi,

I'm trying to select a range in a dataframe every time x <= 20 and create a new dataframe with a column which is the sum of the selected rows (negative value include) of that range and keep the last date as index. Thanks for some hints and if I'm on the right way :)

something like this --->
(Date as index)

This is what I tried so far but doesn't work

Date         x             Date         sum
2019-01-01   100           2019-01-05   353
2019-01-02   120   --->    2019-01-10   804
2019-01-03    80           2019-01-15   650
2019-01-04    48           2019-01-20   428
2019-01-05     5           ...
2019-01-06   110           ...
2019-01-07   420
2019-01-08   140
2019-01-09   126
2019-01-10     8
2019-01-11    50
2019-01-12   160   
2019-01-13   280
2019-01-14   148
2019-01-15    12
2019-01-16   190
2019-01-17   120
2019-01-18    80
2019-01-19    48
2019-01-20   -10
...
...

#######
for date in df.index.to_series().dt.date.unique():
   for row in df.itertuples():
      for i in row:
         if i <= 20:
           new_df = pd.DataFrame(columns=df.keys())
           new_df.index.name = 'Date'
           new_df ['sum'] = df.sum(axis = 0)
         continue: