df.sort_index ()
df.idxmax (0) index of the maximum value, the parameter shaft
df.cumsum () tired and
s.unique () does not repeat all the values
s.nunique () is not worth repeating number
s.drop_duplicates () to heavy
df.sort_index ()
df.idxmax (0) index of the maximum value, the parameter shaft
df.cumsum () tired and
s.unique () does not repeat all the values
s.nunique () is not worth repeating number
s.drop_duplicates () to heavy