title: How to repeat an input if the user didn't type in anything and edit the entered input in matlab?
body: <p>For example I have </p>
  
  <pre><code>
  x = input('value = ?')
  </code></pre>
  
  <p>how can I repeat this command if the user just press enter without any input and I would like to know is there anyway I could edit my input like just pressing the 'backspace' after I have keyed in.</p>
  
  <p>Like I got two input variable now'
  <pre><code>
  x = input('??');
  y = input('???');
  </pre></code>
  can I edit my first input if I have insert the first input data for x when the input function y is prompted out.</p>
  
  <p>sincerely thanks for anyone that willing to give some helps.</p>
  
  <p>For the 1st case:</p>
  
  <p>I would like to have a code something like this</p>
  
  <p><pre><code>
  x = input('value = ?');
  while x == %%no input%%
      x = input('value = ?'); %prompt the input command again
  end
  </pre></code></p>
  
  <p>and </p>
  
  <p><pre><code>
  while x==error %% I want x in numeric input only
      x = input('value = ?'); %prompt the input command again
  end
  </pre></code></p>