rename certain value in pandas series

Question

I have the following panda Series:

print(df.head())
          Country  Energy Supply Energy Supply per Capita  % Renewable
0     Afghanistan   3.210000e+08                       10    78.669280
1         Albania   1.020000e+08                       35   100.000000
2         Algeria   1.959000e+09                       51     0.551010
3  American Samoa            NaN                      ...     0.641026
4         Andorra   9.000000e+06                      121    88.695650

How can I rename Afghanistan to Afghanistan_new? I can set the index:

df = df.set_index('Country')

and then try to rename the country the following way:

df['Afghanistan'].rename('Afghanistan_renamed')

but it doesn't work.

Answer 1

You can use if need replace index:

df = df.set_index('Country')
df = df.rename(index={'Afghanistan':'Afghanistan_renamed'})
print (df)
                     Energy Supply Energy Supply per Capita  % Renewable
Country                                                                 
Afghanistan_renamed   3.210000e+08                       10    78.669280
Albania               1.020000e+08                       35   100.000000
Algeria               1.959000e+09                       51     0.551010
American Samoa                 NaN                      ...     0.641026
Andorra               9.000000e+06                      121    88.695650

and for replace column:

df['Country'] = df['Country'].replace({'Afghanistan':'Afghanistan_renamed'})
df = df.set_index('Country')
print (df)
                     Energy Supply Energy Supply per Capita  % Renewable
Country                                                                 
Afghanistan_renamed   3.210000e+08                       10    78.669280
Albania               1.020000e+08                       35   100.000000
Algeria               1.959000e+09                       51     0.551010
American Samoa                 NaN                      ...     0.641026
Andorra               9.000000e+06                      121    88.695650

Answer 2

You can just use replace() instead rename():

df['Country'].replace({'Afghanistan':'Afghanistan_renamed'}, inplace=True)