Need to multiply matrix diagonals, but with periodic boundary conditions.

Hi, I need to obtain a vector containing the product of each diagonal of a matrix, say A, but with periodic boundary conditions.

Unfortunately X=diag(A,k) does not invoke the necessary periodic condition.

So for example, for A = (1 2 3, 4 5 6, 7 8 9)

I would expect to obtain V=(45, 48, 135)..

Can anyone help me?