DataFrame | multiply set of colums

General Usage
1

Would you suggest,
I have a list of columns (many of them). How to multiply all of them.

I know how to sum, but I have no idea, how to multiply

sum.(eachrow(qf[:,[:a,:b]]))

Thanks

2 
prod.(eachcol(df))
prod.(eachrow(df))

or

prod(Matrix(df), dims=1)
prod(Matrix(df), dims=2)
2 Likes
3

These work:

prod(Matrix(df), dims=1)

or if you want DataFrame

prod(Matrix(df), dims=1) |> x->DataFrame(x, names(df))

or

reduce((x, y)->Vector(x) .* Vector(y), eachrow(df)) |> x->DataFrame(x', names(df))
4

prod.(eachcol(df)) is very clever. Why can’t I think of that…

5

thanks. yes, it’s very clear. for some reasons, I tried mul. =))