I ran into a problem when running a Julia script. The following code produces an error:
UndefVarError: .* not defined
The offending Code:
group = groupby(my_dataframe, [:COLUMN_1, :COLUMN_2]) better_df = @combine(group, :NEW_COLUMN = sum(:COLUMN_4 .* :COLUMN_5))
What I am trying to do is group by two columns and sum the product of two other columns when grouping. It is unclear to me why I get the UndefVarError. My understanding is that the .* operator will multiply the values in the two columns row by row. Am I missing something?