Substracting all elements in two arrays with different sizes

I would like to substract each element in array 1 from each element in array 2. The arrays have different sizes. Basically i would like to achive this:

a1 = (1, 2)

a2 = (1, 2, 3)

a_result = (1-1, 2-1 ,1-2 , 2-2, 1-3, 2-3)

Any tips on how to do this?

Answer 1

[Riccardo Scorretti]

Enjoy ...

a1 = [1 2];
a2 = [1 2 3];
res = a1.' - a2 ; res = res(:).'

res = 1×6

0 1 -1 0 -2 -1

Pay attention to the fact that a1 and a2 must be row-vectors (= not column-vectors), otherwise you will have to modify a little bit.

The general idea is that a1.' is a column vector, and a2 is a row-vector. In Matlab colum-vector (op) row-vector returns a matrix, the entries of which are the result of the operation between each couple of elements of the two vectors.

[KuriGohan]

Thank you very much.