Summing the diagonal of a matrix "the other way"?

I don't know if I'm wording it correctly, but I'm trying to sum the diagonal of a matrix the other "direction" than the diag(A) function. For example, I have a matrix:

 A =
 1 2 3 4
 5 6 7 8
 9 10 11 12
 13 14 15 16

If I use diag(A), it'd give me 1 + 6 + 11 + 16, but I'm looking for:

 1
 2 + 5
 3 + 6 + 9
 4 + 7 + 10 + 13

And put all the sums in a 1xn array, much like a Fibonacci sequence. Is there a function that can do this, or can diag(A) be altered in someway?

[Aquatris]

Try this solution ; https://www.mathworks.com/matlabcentral/answers/294766-most-efficient-way-to-sum-anti-diagonal-elements

Answer 1

[Birdman]

This can be done as follows:

 res=[sum(diag(fliplr(A),3)) sum(diag(fliplr(A),2)) sum(diag(fliplr(A),1)) sum(diag(fliplr(A)))]

or it can be done in a for loop:

 for i=1:size(A,1)
     res(i)=sum(diag(fliplr(A),size(A,1)-i))
 end