python - Find maximum value of a column and return the corresponding row values using Pandas -

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structure of data;

using python pandas trying find 'country' & 'place' maximum value.

this returns maximum value:

data.groupby(['country','place'])['value'].max()

but how corresponding 'country' , 'place' name?

assuming df has unique index, gives row maximum value:

in [34]: df.loc[df['value'].idxmax()] out[34]:  country        place      kansas value         894 name: 7

note idxmax returns index labels. if dataframe duplicates in index, label may not uniquely identify row, df.loc may return more 1 row.

therefore, if df not have unique index, must make index unique before proceeding above. depending on dataframe, can use stack or set_index make index unique. or, can reset index (so rows become renumbered, starting @ 0):

df = df.reset_index()

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