title: How to convert nanoseconds to milliseconds
body: <p>I'm trying to get <code>milliseconds</code> from <code>NSCalendarUnit</code>. I was able to get <code>nanosecond</code>, but that has way too many numbers. All I want is 2 numbers. Here is my code:</p>
  
  <pre><code>var startDate = NSDate()
  let dateComponents = NSCalendar.currentCalendar().components(NSCalendarUnit.CalendarUnitNanosecond, fromDate: startDate, toDate: NSDate(), options: nil)
  
  let strFraction = String(format: "%02d", dateComponents.nanosecond)
  timeLabel.text = "\(strFraction)"
  </code></pre>
  
  <p>How can I get milliseconds from the NSCalendarUnit?</p>