{HEAD ~ an angle} calculating {TAIL ~ section} for calculating a plurality of angle data representing said geometric placement of said arc welding torch at every teaching points, by using said plurality of position and orientation data obtained in said data obtaining section and said virtual reference plane set in said reference plane setting section; and 
calculating
{ HEAD ~ an angle } calculating { TAIL ~ section } for calculating a plurality of angle data representing said geometric placement of said arc welding torch at every teaching points , by using said plurality of position and orientation data obtained in said data obtaining section and said virtual reference plane set in said reference plane setting section ; and
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH