title: unix timestamp to boost::posix_time::ptime
body: <p>I need to convert double with number of seconds since the epoch to <code>ptime</code>. I'm prety sure there must be an easy way to do this, but I couldn't find anything. Thanks.</p>
  
  <p>Edit: The original timestamp is floating point. I can't change it and i don't want to lose the sub-second precision.</p>