title: how to check for extended ascii characters in matlab
body: <p>Does anyone know how to detect non ASCII characters in matlab. </p>
  
  <p>i thought of detecting the presence of non ASCII characters through regular expressions</p>
  
  <pre><code>if (regexpi('hello world%^&amp;%','![A-Z]*'))display('You have non ascii characters')
  </code></pre>
  
  <p>but it doesn't seem to work</p>
  
  <p>update:- </p>
  
  <pre><code>   if (regexpi('hello word','^[A-Za-z0-9]*'))
     display('You have chosen to overwrite!');
     end
  </code></pre>
  
  <p>displays You have chosen to overwrite!</p>