# Put vector of vector into vector of vector without for loop

Consider the following minimal example:

``````A = [Vector{Int}(undef, 5) for i = 1:4]
a = [zeros(Int, 2) for i = 1:4]
``````

I’d like to put `a` into the first 2 inner indices of `A` without a for loop. Is that possible?
Something like:

``````A[:][1:2] = a
``````

but this errors with:

``````ERROR: DimensionMismatch("tried to assign 4 elements to 2 destinations")
``````
``````julia> A[1:2] .= a[1:2]; A
4-element Array{Array{Int64,1},1}:
[0, 0]
[0, 0]
[1, 2, 3, 4, 5]
[1, 2, 3, 4, 6]
``````

Thank you, but it is not exactly what I wanted.
Consider `A` and `a` like

``````A = [ones(4) for i = 1:4]
4-element Array{Array{Float64,1},1}:
[1.0, 1.0, 1.0, 1.0]
[1.0, 1.0, 1.0, 1.0]
[1.0, 1.0, 1.0, 1.0]
[1.0, 1.0, 1.0, 1.0]

julia> a = [zeros(2) for i = 1:4]
4-element Array{Array{Float64,1},1}:
[0.0, 0.0]
[0.0, 0.0]
[0.0, 0.0]
[0.0, 0.0]
``````

The output I like would be:

``````4-element Array{Array{Float64,1},1}:
[0.0, 0.0, 1.0, 1.0]
[0.0, 0.0, 1.0, 1.0]
[0.0, 0.0, 1.0, 1.0]
[0.0, 0.0, 1.0, 1.0]
``````

I get,

`ERROR: UndefVarError: .= not defined`

Are you still using Julia 0.4? I highly recommend you upgrade.

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