Why do my loop never end?

Hi! In my function my while loop never ends and I can't understand why. I'm making the bisect algorithm and want to save every left and right x I test.

The error I get (after using ctrl + C): Operation terminated by user during bisektion2 (line 60)

The loop looks like this:

while X(i)-x(i)>tol % continue as long as the interval is longer
  % than the given tolerance
  i=i+1;              %add 1 to i
  if fxx==0
      return % break and return x
  end
  if ((fx*fxx)<0)  %if fx * fxx is <0 the answer is on the left side of the interval
      X(i)=xx;
      x(i)=x(i-1);
      fX=fxx;
  else %on the right side of the interval
      x(i)=xx;
      X(i)=X(i-1);
      fx=fxx;
  end
  disp(i);
end

Answer 1

[Azzi Abdelmalek]

That means that X(i)-x(i)>tol is always true