title: Validating a floating value in PHP
body: <p>I started learning PHP to do some pet project, and I am trying to get this around my head on how to validate a valid float or double in PHP</p>
  
  <p>Supposed I have this code in HTML that ask for interest rate</p>
  
  <pre><code>&lt;input type="text" name="interest" size="5" &gt;
  </code></pre>
  
  <p>In My PHP code, I wanted to validate if this is a valid interest rate:</p>
  
  <pre><code>&lt;?php       
      $interest = $_POST['interest']
      //isset - empty test (not- shown)
      if(!is_numeric($interest) &amp;&amp; is_float($interest)){
          print "&lt;p&gt;&lt;span class='error'&gt;Interest should be numeric&lt;/span&gt;&lt;/p&gt;";
      }
  ?&gt;
  </code></pre>
  
  <p>I have my is_numeric()  test first then I coupled it with the is_float() test but when I enter "1." (note the "." after the number) it should catch this but apparently not.  I am not sure why "1." is a valid floating variable in PHP.</p>