how to do a left,right and mid of a string in a pandas dataframe

Question

in a pandas dataframe how can I apply a sort of excel left('state',2) to only take the first two letters. Ideally I want to learn how to use left,right and mid in a dataframe too. So need an equivalent and not a "trick" for this specific example.

data = {'state': ['Auckland', 'Otago', 'Wellington', 'Dunedin', 'Hamilton'], 'year': [2000, 2001, 2002, 2001, 2002], 'pop': [1.5, 1.7, 3.6, 2.4, 2.9]} df = pd.DataFrame(data)  print df       pop       state  year  0  1.5    Auckland  2000  1  1.7       Otago  2001  2  3.6  Wellington  2002  3  2.4     Dunedin  2001  4  2.9    Hamilton  2002 

I want to get this:

    pop       state     year  StateInitial  0  1.5       Auckland    2000     Au  1  1.7       Otago       2001     Ot  2  3.6       Wellington  2002     We  3  2.4       Dunedin     2001     Du  4  2.9       Hamilton    2002     Ha 

Answer 1

First two letters for each value in a column:

>>> df['StateInitial'] = df['state'].str[:2] >>> df    pop       state  year StateInitial 0  1.5    Auckland  2000           Au 1  1.7       Otago  2001           Ot 2  3.6  Wellington  2002           We 3  2.4     Dunedin  2001           Du 4  2.9    Hamilton  2002           Ha 

For last two that would be df['state'].str[-2:]. Don't know what exactly you want for middle, but you can apply arbitrary function to a column with apply method:

>>> df['state'].apply(lambda x: x[len(x)/2-1:len(x)/2+1]) 0    kl 1    ta 2    in 3    ne 4    il