Below is a small tidbit of code that operates on the matrix vel and updates its values. When I check the values of the indices in the matrix, every single element, barring vel(1,1), vel(1,2), and vel(1,3), is equal to 0.
vel := Matrix(3, 241, datatype = float[8]);
step := 0.1;
vel(1, 1) := 5; vel(2, 1) := 95; vel(3, 1) := 3;
UpdateAllVelocities := proc (i, vel::Matrix, accel::Matrix, step);
#I understand these calls are quite pointless......