title: MatLab - Newton's method algorithm
body: <p>I have written the following algorithm in order to evaluate a function in MatLab using Newton's method (we set r = -7 in my solution):</p>
  
  <pre><code>function newton(r);
  syms x;
  y = exp(x) - 1.5 - atan(x);
  yprime = diff(y,x);
  f = matlabFunction(y);
  fprime = matlabFunction(yprime);
  x = r;
  xvals = x
  for i=1:8 
      u = x;
      x = u - f(r)/fprime(r);
      xvals = x
  end
  </code></pre>
  
  <p>The algorithm works in that it runs without any errors, but the numbers keep decreasing at every iteration, even though, according to my textbook, the expression should converge to roughly -14 for x.  My algorithm is correct the first two iterations, but then it goes beyond -14 and finally ends up at roughøy -36.4 after all iterations have completed.</p>
  
  <p>If anyone can give me some help as to why the algorithm does not work properly, I would greatly appreciate it!</p>