Index of max values of N columns in a DataFrame without manually entering each column

[rocco_sprmnt21]

or maximum for row-wise maximum using the zip function

maximum.(zip([df[!,c] for c in names(df) if c!="C"]...));

df[sortperm([maximum(r) for r in zip([df[!,c] for c in filter(!=("C"), names(df) )]...)], lt= >= ),:]

PS

it seems that the last form has problems.