How can I get the number of unique ip addresses per user id in a pandas DataFrame?

Question

I have this DataFrame:

    user_id     ip
 0        2       106.184.2.137
 1        2       106.184.2.137
 2        3       106.184.2.113
 3        3       106.184.2.112
 4        9       103.105.111.191
 5        9       103.105.111.191
 6       11       103.239.29.190

How can I get the number of unique ip addresses per user id as follows:

    user_id     ip_num
 0        2       1
 1        3       2
 2        9       1
 3        11      1

thank you for your help.

Answer 1

Like this:

df = df.groupby('user_id')['ip'].nunique().reset_index().rename(columns={'ip': 'ip_num'})