MATLAB: Function Subtracts Two Nonnegative Integers

nonnegative integerssubtraction

My task is to create a MATLAB function that subtracts two nonnegative integers. x, y, and x_minus_y are row vectors representing nonnegative integers. I have a program that works for most cases except for some such as 'ex6(7500,7499)'. I am not sure why the program is not working for this case. Here is what I have:
function x_minus_y = ex6(x,y)
%
%
x = [0 x];
xLength = length(x);
yLength = length(y);
y = [zeros(1, xLength – yLength), y];
x_minus_y = x – y;
for position = xLength:-1:2
if x_minus_y(position) < 9
x_minus_y(position) = x_minus_y(position) + 10;
x_minus_y(position – 1) = x_minus_y(position – 1) + 1;
end
end
if x_minus_y(1) = 0
x_minus_y = x_minus_y(2:end);
end

Best Answer

For your if conditional, use two = for comparison.
if x_minus_y(1) == 0