Pandas: remove rows of dataframe with unique index value

Question

I am trying to remove the rows of my dataframe (df) which have unique value as index. This is my df:

    A       B
1   3.803   4.797
1   3.276   3.878
2   5.181   6.342
3   6.948   9.186
3   8.762  10.136
4  10.672  12.257
4   8.266  13.252
5  13.032  14.656
6  15.021  17.681
6  16.426  15.07

I would like to remove the rows with index=2,5 to get a new dataframe (df_new) as follow:

    A       B
1   3.803   4.797
1   3.276   3.878
3   6.948   9.186
3   8.762  10.136
4  10.672  12.257
4   8.266  13.252
6  15.021  17.681
6  16.426  15.07

Is there some handy function in pandas to do that? Thank you

Answer 1

Use get_duplicates :

In [36]:
df.loc[df.index.get_duplicates()]

Out[36]:
        A       B
1   3.803   4.797
1   3.276   3.878
3   6.948   9.186
3   8.762  10.136
4  10.672  12.257
4   8.266  13.252
6  15.021  17.681
6  16.426  15.070

get_duplicates returns an array of the duplicated indices:

In [37]:
df.index.get_duplicates()

Out[37]:
[1, 3, 4, 6]