title: Extract double number value with exponent from text
body: <p>How could I extract a number of type double which may have exponent from a string with more character?</p>
  
  <p>For example extract <code>56.8671311035e-06</code> from</p>
  
  <blockquote>
    <p>"this is a string with a number inside 56.8671311035e-06 and the string continues here"</p>
  </blockquote>
  
  <p>I guess it could be done using regular expressions, but my knowledge of them is very limited.</p>