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

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

```
prod.(eachcol(df))
prod.(eachrow(df))
```

or

```
prod(Matrix(df), dims=1)
prod(Matrix(df), dims=2)
```

2 Likes

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))
```

`prod.(eachcol(df))`

is very clever. Why canâ€™t I think of thatâ€¦

thanks. yes, itâ€™s very clear. for some reasons, I tried mul. =))