I'd like to calculate only A(a)*B(b)
Have you checked what A(a) and B(b) look like? They are both vectors of different sizes so A(a)*B(b) has no clear definition,
>> A(a)
ans =
-1
-7
-5
-3
-9
>> B(b)
ans =
-1
-7
-5
-3
-9
-1
-7
-5
-3
-9
If you want all combinations of products A(a(i))*B(b(j)), you don't need bsxfun at all. It's just an outer product calculation,
A(a)*B(b).'
If this is not what you want, then you need to clarify what the final result should look like.
