Calculate value based on previous row plus adjacent row

Hi,

I have a matrix of two columns and need to calculate the values of the second column based on the previous row of column 2 plus the adjacent row of column 1. For example,

Given the above matrix, cell B4 has been calculated by getting the value of cell B3 + A4. This carries on for the duration of the matrix.

I can do this quite easily in Excel but am finding it rather difficult in Matlab.

Any help/suggestions would be greatly appreciated please.

Answer 1

[Adam]

For that particular example:

B = cumsum( A )';

Answer 2

[Azzi Abdelmalek]

idx=1:6
out=B(idx)+A(idx+1)

Answer 3

[Thorsten]

 A = [0:5];
 B = [0 1 3 6 10 15];
 ind = 3:6;
 C(ind) = A(ind) + B(ind-1)

 M = [A' B' C']