CODE EXAMPLE FOR PYTHON

get from time secs and nsecs

   t = rospy.Time.from_sec(time.time())
   seconds = t.to_sec() #floating point
   nanoseconds = t.to_nsec()
   
   d = rospy.Duration.from_sec(60.1)  # One minute and one tenth of a second
   seconds = d.to_sec() #floating point
   nanoseconds = d.to_nsec()