Try the cat, hcat, vcat family of functions.
--Tim
On Saturday, April 04, 2015 05:04:21 PM Tamas Papp wrote:
> Hi,
>
> Suppose I have a function that maps an atom of type T, eg Float64, into
> Vector{T}, and takes another argument n that determines its length.
>
> What is the idiomatic/fast way of collecting the values in the columns
> of a matrix?
>
> Currently I am using this:
>
> @doc """Map elements of `x` into columns of a matrix using `f`.
> Result is assumed to have the same element type as `x`.""" ->
> function maptocols{T}(f,x::Vector{T},n)
> k = length(x)
> b = Array(T, n, k)
> for j = 1:k
> b[:,j] = f(x[j],n)
> end
> b
> end
>
> Eg
>
> julia> maptocols((x,n) -> x.*[1:n;], [1,2,3,4], 4)
> 4x4 Array{Int64,2}:
> 1 2 3 4
> 2 4 6 8
> 3 6 9 12
> 4 8 12 16
>
> which is OK but of course I would prefer a one-liner if there is one
> provided by the language (could not find it though).
>
> Best,
>
> Tamas
