用选定的列表值填写 dataframe 中的列

Question

I have a lot of addresses in excel file. I have import it and store it in dataframe. Now I want to detect the states in each address and show it in new column. How do I loop for every row in my dataframe and add the value of the states in that row?

List of all states:

allstates=['SELANGOR','JOHOR','KELANTAN','MALACCA','NEGERI SEMBILAN','PAHANG','PENANG','PERAK','PERLIS',
          'SABAH','SARAWAK','TERENGGANU','KUALA LUMPUR','K. LUMPUR','LABUAN','PUTRAJAYA']

and below is how I want my dataframe to be:

Address                             |    States
-------------------------------------------------------
311 Jalan Springhill SELANGOR       |    *SELANGOR*
31 Jalan Segamat JOHOR              |    *JOHOR*

I want the states (example:SELANGOR) to insert in the states column

Answer 1

Try this:

df['States'] = df.Address.str.extract('({})'.format('|'.join(allstates)))

If you are certain (or want) that the state names appear only at the end of the addresses:

df['Sates'] = df.Address.str.extract('({})$'.format('|'.join(allstates)))

Output:

                         Address     Sates
0  311 Jalan Springhill SELANGOR  SELANGOR
1         31 Jalan Segamat JOHOR     JOHOR

Answer 2

import pandas as pd
data = pd.read_csv('states.csv')
print(data)
                         Address
0  311 Jalan Springhill SELANGOR
1         31 Jalan Segamat JOHOR

for index, row in data.iterrows():
    value = row.Address
    State = value.split()[-1:][0]
    data.loc[index,'State'] = State

print(data)
                         Address     State
0  311 Jalan Springhill SELANGOR  SELANGOR
1         31 Jalan Segamat JOHOR     JOHOR