[julia-users] conversion Vector{Vector{T}} <-> Matrix{T}

[Alex]

Hi together,

It seems to be quite natural to try converting Vector{Vector{T}} into 
Matrix{T} or vice versa. Is this conversion problematic in some way? What 
would be an efficient way to achieve it?

As a first attempt I would do
y = [[i,i] for i=1:3]

mat = Array(eltype(y[1]),length(y),length(y[1]))

for i=1:length(y)
        mat[i,:] = y[i]
end

to get the matrix. And

v = vcat(Vector{eltype(mat[1,1])}[mat[i,:][:] for i=1:size(mat,1)])

I am sure there are more elegant ways of doing this.

Thanks!

- Alex.