pandas 选择 to_datetime 的原始格式

Question

I have the following df:

df

index          Original Date                          
19.02.2021     19.02.2021  
19.02.2021     19.02.2021  
...                 
04.12.2020     04.12.2020 
03.12.2020     03.12.2020

I would like to set index column as an index, however it is at the moment string type object so, I convert it to datetime object and then set as an index.

df['index'] = pd.date_time(df['index'])
df = df.set_index('index')

It looks like this:

df

             Original Date
index          
2021-02-19   19.02.2021
2021-02-19   19.02.2021
2021-02-18   18.02.2021
2021-02-18   18.02.2021
2021-02-17   17.02.2021
...
2020-04-12   04.12.2020
2020-03-12   03.12.2020

As you can see pandas can succesfully convert some of the dates. However some days like 04.12.2020 is converted to 12.04.2020 . So how can I specify the original format is 'dd.mm.yyyy' , so that pandas can convert this string object to datetime successfully.

Answer 1

You can add the format as a parameter

df.index = pd.to_datetime(df.index, format = '%d.%m.%Y')

Answer 2

Try the following:

df.index = pd.to_datetime(df.index, format = '%Y-%m-%d').strftime('%d.%m.%Y')