code: public static double getDistance(final TPVObject tpv1, final TPVObject tpv2) {
  		return GISTool.getDistance(tpv1.getLongitude(), tpv2.getLongitude(), tpv1.getLatitude(), tpv2.getLatitude());
  	}
docs: calculates the distance between two {@link TPVObject} in kilometers<br>
  the method used is the great-circle-distance with hypersine formula
  
  @param tpv1 - position 1
  @param tpv2 - position 2
  @return distance in kilometers