nl_tokens: return the Ersatz ( squared ) distance between two stops in undefined units
pl_tokens: function stopDistance ( s1 : Stop , s2 : Stop ) : number { const cosLat = Math . <mask> ( s1 . stop_lat * Math . PI / 180 ) return Math . pow ( s1 . stop_lat - s2 . stop_lat , 2 ) + Math . pow ( s1 . stop_lon * cosLat - s2 . stop_lon * cosLat , 2 ) }