Convert a column to a specific date format which contains different formats of date in python

Question

This is my data frame

 df = pd.DataFrame({
'Date': ['01/05/2015', '15 Jul 2009', '21.03.12','2021.03.12']
 })


     Date
0   01/05/2015
1   15 Jul 2009
2   21.03.12
3   2021.03.12

I want all the dates from 'Date' column in yyyy-mm-dd format. The expected output is given below

     Date
0   2015-01-05
1   2009-07-15
2   2021-03-12
3   2021-03-12

But i am getting

Date
0   2015-01-05
1   2009-07-15
2   2012-03-21
3   2021-03-12

Here, the format 21.03.12 is not recognized as yy.mm.dd .To rectify this I added '20' infront of yy.mm.dd format dates, this works but not a permanent solution. Is there any better solution for this?

Thanks in advance!

Answer 1

I think you're after this:

import pandas as pd

df = pd.DataFrame({
    'Date': ['01/05/2015', '15 Jul 2009', '21.03.12', '2021.03.12']
})

df['Current'] = pd.to_datetime(df['Date'])
df['Desired'] = pd.to_datetime(df['Date'], yearfirst=True)

print(df)

Result:

          Date    Current    Desired
0   01/05/2015 2015-01-05 2015-01-05
1  15 Jul 2009 2009-07-15 2009-07-15
2     21.03.12 2012-03-21 2021-03-12
3   2021.03.12 2021-03-12 2021-03-12

In 'Desired', note how 21 is now interpreted as the year.