title: Regex to disallow hyphen at only first place
body: <p>I am newbee in regex so caught on a problem, I googled but unfortunately didn't got the solution so here my problem is :<br>
  I need a regex which disallow hyphen as first character(If it is the only character in the string)</p>
  
  <blockquote>
    <p>Eg: - (disallow)</p>
  </blockquote>
  
  <p>But if I write some digit with it then it should allow it, and also allow fraction values
  and also it should not allow any alphabets</p>
  
  <blockquote>
    <p>Eg:<br>
     1234 (allow)<br>
    -1234 (allow)<br>
    -1234.1234 (allow)</p>
  </blockquote>
  
  <p>No alphabets should be allowed in entire strings and no repetition of hyphen.</p>
  
  <p>This is what I have tried so far:</p>
  
  <blockquote>
    <p>((^-?[0-9]{0,4})|(^-?[0-9]{0,4}))(.[0-9]{1,4})?</p>
  </blockquote>
  
  <p>It works fine for all scenario except 
  single hyphen ie</p>
  
  <blockquote>
    <p>eg: - (it is allowed using my regex but I shouldn't)</p>
  </blockquote>
  
  <p>The help is truly appreciated.. :)</p>