CUSUM   (matrix)   ; 
            
The CUSUM function computes cumulative sums. The argument to this function is a numeric matrix or literal.
The CUSUM function returns a matrix of the same dimension as the argument matrix. The result contains the cumulative sums obtained by adding the nonmissing elements of the argument in row-major order.
For example, the following statements compute cumulative sums:
a = cusum({1 2 4 5});
b = cusum({5 6, 3 4});
print a, b;
Figure 23.81: Cumulative Sums
| a | |||
|---|---|---|---|
| 1 | 3 | 7 | 12 | 
| b | |
|---|---|
| 5 | 11 | 
| 14 | 18 |