获取python panda数据框的行名作为字符串

Question

Having found the maximum value in a panda data frame column, I am just trying to get the equivalent row name as a string.

Here's my code:

df[df['ColumnName'] == df['ColumnName'].max()].index

Which returns me an answer:

Index(['RowName'], dtype='object')

How do I just get RowName back?

(stretch question - why does .idmax() fry in the formulation df['Colname'].idmax ? And, yes, I have tried it as .idmax() and also appended it to df.loc[:,'ColName'] etc.)

Answer 1

Just use integer indexing:

df[df['ColumnName'] == df['ColumnName'].max()].index[0]

Here [0] extracts the first element. Note your criterion may yield multiple indices.