title: Formatting of scientific numbers
body: <p>Trying to print out a scientific number, I have tried different kinds of PHP number formats, including sprintf, etc.</p>
  
  <pre><code>&lt;?php
  $layer1capacityratio = 3.9008133852857E-5;
  echo sprintf('%f',$layer1capacityratio);
  </code></pre>
  
  <p>This outputs "0.000039" but I would like to output "0.003901%".</p>
  
  <p>I am not sure what I have missed. If someone can point me in the right direction I would be grateful!</p>