title: Is there any code for 3D LOG filtering (or scale-normalized LoG filtering) for Matlab?
body: <p>I want to use '<strong>scale-normalized LoG filtering</strong>' and so I try to use, <code>h = fspecial3('log',hsize,sigma);</code> but, when it is run an error occurs that 'No help found for fspecial3'. Whereas,<code>fspecial3</code> is found in this <a href="https://www.mathworks.com/help/images/ref/fspecial3.html#d120e64047" rel="nofollow noreferrer">link</a>. 
  How to solve it?</p>