Pandas - Extract a string starting with a particular character

Question

I have a data frame named df1, having a column "name_str". Example below:

name_str 

0 alp:ha

1 bra:vo

2 charl:ie

I have to create another column which would comprise say 5 characters that start after the colon (:). This is the code I have used:

import pandas as pd

data = {'name_str':["alp:ha", "bra:vo", "charl:ie"]}

#indx = ["name_1",]

df1 = pd.DataFrame(data=data)

n= df1['name_str'].str.find(":")+1

df1['slize'] = df1['name_str'].str.slice(n,2)

print(df1)

But the output is disappointing: NaanN

name_str slize

0 alp:ha NaN

1 bra:vo NaN

2 charl:ie NaN

The output should have been:

name_str slize

0 alp:ha ha

1 bra:vo vo

2 charl:ie ie

Answer 1

Use str.extract to extract everything after the colon with this regular expression: :(.*)

df1['slize'] = df1.name_str.str.extract(':(.*)')

>>> df1

name_str slize

0    alp:ha    ha

1    bra:vo    vo

2  charl:ie    ie

OR

df['slize'] = df1.name_str.str.extract(':(.{,5})') 

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