Get value which occurred the most for an id in DataFrame

Question

I have a DataFrame with several ids, every id has a category. My result should contain the category which occurred the most for a certain id.

Example:

id  categorie

1   aaa

1   aaa

2   bbb

2   bbb

2   aaa

3   aaa

3   ccc

3   ccc

Result:

id  categorie

1   aaa

2   bbb

3   ccc

I tried several .groupby() approaches but none have worked so far.

Answer 1

You can just do this:

df = df.groupby(by=['id'], as_index=False)['categorie'].max()

Or:

df = df.groupby(by=['id'], as_index=False).agg(lambda x:x.value_counts().index[0])

print(df)

   id categorie

0   1       aaa

1   2       bbb

2   3       ccc

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