title: How to exit a matlab m-file (NOT the matlab itself) if the user enters bad inputs?
body: <p>How to exit a matlab m-file (NOT the matlab itself) if the user enters bad inputs?
  I know if a m-file goes wrong at run time we can press Ctrl-C to stop it. but I need a command to put it in my m-file to do so if something bad happens. </p>
  
  <p>Please don't suggest 'exit' or 'quit' commands as they terminate the entire matlab and I don't want it.</p>