Formatting date in a dataframe

[WiPi]

Hi guys,

I have a pandas generated dataframe (df) where the first column has a series of dates as below:

Output:
0    11.26.2020 03:36
1    12.01.2020 15:00
2    12.01.2020 21:30
3    12.02.2020 13:26
4    12.04.2020 22:43
5    12.21.2020 00:05

I need to change these dates to a format YY,MM,DD H:M
If I look at the raw values in the df array:

df.values[:,0]

Output:
array(['11.26.2020 03:36', '12.01.2020 15:00', '12.01.2020 21:30',
       '12.02.2020 13:26', '12.04.2020 22:43', '12.21.2020 00:05'],
      dtype=object)

We need to change these values to a DateTimeIndexArray and then parse to the correct string format:

dti = pd.to_datetime(df.values[:,0])
dti = dti.strftime('%Y.%m.%d %H:%M')
dti.values

This code gives this output:

Output:
array(['2020.11.26 03:36', '2020.12.01 15:00', '2020.12.01 21:30',
       '2020.12.02 13:26', '2020.12.04 22:43', '2020.12.21 00:05'],
      dtype=object)

So it looks like it's done what I want!
Copying back the re-formatted dates to the df:

df.values[:,0] = dti.values

This does not work! The dates remain in the original format.

Any ideas please?