title: Regular Expression to avoid negative values
body: <p>I am totally new to creating my own regular expressions. I have one reg ex developed my team member as listed below</p>
  
  <pre><code>  ^\s*-?\d{1,3}(\.\d{1,4})?\s*$
  </code></pre>
  
  <p>This will ensure that the value entered is having a maximum of 3 digits and may or may not have a negative sign.</p>
  
  <p><a href="http://www.sweeting.org/mark/html/revalid.php" rel="nofollow">RegExp Calculator</a></p>
  
  <p>If I test with a value, “-1000” it will say the entered value does not meet the requirements and an error will be shown to the user.</p>
  
  <p>I need to modify the expression in such way that:</p>
  
  <p><code>If a “-“ sign is there, it can have more than 3 digits and decimals. [But if the user enter a “-“ and any alphabets, it should not match ]</code></p>