MATLAB: Substraction with sum / loop

Question

Hello everybody !

I have a vector A and a matrix B

A= [10 20 30] 
B=  2 5  10
    4 10 20
    6 15 30

so if I want to calculate the following matrix : here I want to substract the first elment of the vector to the first column by and then the second element to the second columns and the third element to the third column..by this way :

   C= 10-2       20-5          30-10
      10-2-4     20-5-10       30-10-20
      10-2-4-6   20-5-10-15    30-10-20-30

So as shown, I want to substract the first element of the vector to the first column elements , substract the first element, keep result then substract to the second element, keep result, substract to the third element .. Thank you

Answer 1

I assume that the FOR loop is not essential.

Result = A - cumsum(B, 1);  % Matlab 2016b autoexpanding

For older Matlab versions:

Result = bsxfun(@minus, A, cumsum(B, 1));