Question

Write a function called sum_half that takes as input a square matrix A and computes the sum of its elements that are in the upper right triangular part of A, that is, elements in the diagonal and elements that are to the right of it. For example, if the input is [1 2 3; 4 5 6; 7 8 9], then the function would return 26. (That is, 1+2+3+5+6+9) Note, the function triu is not allowed. Please write as you would in MATLAB

Answer 1

function [sum] = sum_half (A)
    sum = 0;
    % if i <= j i.e, above the diagonal matrix
    for i=1:length(A)
        for j = 1:length(A(i,:))
            if i <=j
                % calculating sum of 
                % upper trianglar matrix
                sum = sum + A(i,j);
            end
        end
    end
    
    % returning sum
    sum;
end

Code

Output