Hi, I have a dataframe df2 and the last column is the sum = b+c :
julia> df2 8x4 DataFrames.DataFrame │ Row │ a │ b │ c │ sum │ ┝━━━━━┿━━━┿━━━┿━━━━━━━━━━━┿━━━━━━━━━━━┥ │ 1 │ 1 │ 2 │ -0.163564 │ 1.83644 │ │ 2 │ 2 │ 1 │ 0.731038 │ 1.73104 │ │ 3 │ 3 │ 2 │ 0.0951149 │ 2.09511 │ │ 4 │ 4 │ 1 │ 0.195321 │ 1.19532 │ │ 5 │ 1 │ 2 │ 1.97058 │ 3.97058 │ │ 6 │ 2 │ 1 │ 0.150826 │ 1.15083 │ │ 7 │ 3 │ 2 │ 0.422046 │ 2.42205 │ │ 8 │ 4 │ 1 │ -1.36549 │ -0.365486 │ we can se that the column a have duplicates (1,2,3). I try to find a simple way to remove the duplicates that have the lowest sum without changing the values of b and c. I tried : julia> aggregate(df2, :a, maximum) 4x4 DataFrames.DataFrame │ Row │ a │ b_maximum │ c_maximum │ sum_maximum │ ┝━━━━━┿━━━┿━━━━━━━━━━━┿━━━━━━━━━━━┿━━━━━━━━━━━━━┥ │ 1 │ 1 │ 2 │ 1.97058 │ 3.97058 │ │ 2 │ 2 │ 1 │ 0.731038 │ 1.73104 │ │ 3 │ 3 │ 2 │ 0.422046 │ 2.42205 │ │ 4 │ 4 │ 1 │ 0.195321 │ 1.19532 │ but this is wrong because I don't want b_maximum and c_maximum but only sum_maximum : Row │ a │ b │ c │ sum_maximum I don't think that there is a simple way to do that but I ask the question in case ;) Thank you very much in advance !