I want to build a test that checks if a matrix has an upper triangular form. But somehow it didn't work in Matlab Grader.
I tried to use the matlab function istriu
A = [1.6537 1.1405 1.2570;
0.0000 0.9661 0.6341;
-0.0000 0.0000 0.8816;
-0.0000 -0.0000 -0.0000;
-0.0000 0.0000 0]
isUpper = istriu(A)
but it gives me always zero back, even though the matrix is upper triangular. When I am doing it locally, it gives me the right answer.
Does someone know why is this happening and how can I solve it?