Assume time column is in timestamp integer msec format
1 day = 86400000 ms
Here you go:
day_divider = 86400000
df['time'] = df['time'].values.astype(dtype='datetime64[ms]') # for msec format
df['time'] = (df['time']/day_divider).values.astype(dtype='datetime64[D]') # for day format
If I have a pandas DataFrame with timestamp column (1546300800000, 1546301100000, 1546301400000, 1546301700000, 1546302000000) and I want to convert this into date time format
This will return a column with the format 2019-01-01 00:00:00, 2019-01-01 00:05:00, 2019-01-01 00:10:00, 2019-01-01 00:15:00, 2019-01-01 00:20:00...etc
Dividing by 1000 to convert from ms to s as explained here