Storing values in a variable

I want to store values in a variable annd return it to another function

For example,

function A = fun()
A([2 3 4]) = [1 4 7]
end

dA([2 3 4]) = fun()

This doesn't work because A has a zero saved at index 1 and fun returns a 4 x 1array.Is there a way to return A as a 3 x 1 array while saving values only at index 2, 3 and 4 ?

[Rik]

If A has only 3 elements, how can you store something in position 4?

[KALYAN ACHARJYA]

@Rik :)

Is there a way to return A as a 3 x 1 array while saving values only at index 2, 3 and 4 ?

@Deepa Why? Is there any logic?