I'm converting a datetime column (referred to as DATE) in my Pandas dataframe df to a string of the form 'Ymd' (e.g. '20191201' for December 1st 2019). My current way of doing that is:
import datetime as dt
df['DATE'] = df['DATE'].apply(lambda x: dt.datetime.strftime(x, '%Y%m%d'))
But this is surprisingly inefficient and slow when run on large dataframes with millions of rows. Is there a more efficient alternative I am not seeing? That would be extremely helpful. Thanks.