[u/mrichter/AliRoot.git] / MINICERN / packlib / kernlib / kerngen / tcgens / vdotn.F

*
* $Id$
*
* $Log$
* Revision 1.1.1.1  1996/02/15 17:50:16  mclareni
* Kernlib
*
*
#include "kerngen/pilot.h"
      FUNCTION VDOTN (X,Y,N)
C
C CERN PROGLIB# F121    VDOTN           .VERSION KERNFOR  2.09  751101
C ORIG. 01/07/71
C
      DIMENSION X(*), Y(*)
C
      IF (N.LE.0) GO TO 100
      XX= 0.
      XY= 0.
      YY= 0.
C
      DO 9 J=1,N
      XX = XX + X(J)*X(J)
      XY = XY + X(J)*Y(J)
    9 YY = YY + Y(J)*Y(J)
C
      VDOTN= XY / SQRT(XX*YY)
      IF (ABS (VDOTN).LT.1.) RETURN
      VDOTN= SIGN (1.,VDOTN)
      RETURN
  100 VDOTN = 0.
      RETURN
      END
Commit	Line	Data
fe4da5cc	1	*
	2	* $Id$
	3	*
	4	* $Log$
	5	* Revision 1.1.1.1 1996/02/15 17:50:16 mclareni
	6	* Kernlib
	7	*
	8	*
	9	#include "kerngen/pilot.h"
	10	FUNCTION VDOTN (X,Y,N)
	11	C
	12	C CERN PROGLIB# F121 VDOTN .VERSION KERNFOR 2.09 751101
	13	C ORIG. 01/07/71
	14	C
	15	DIMENSION X(), Y()
	16	C
	17	IF (N.LE.0) GO TO 100
	18	XX= 0.
	19	XY= 0.
	20	YY= 0.
	21	C
	22	DO 9 J=1,N
	23	XX = XX + X(J)*X(J)
	24	XY = XY + X(J)*Y(J)
	25	9 YY = YY + Y(J)*Y(J)
	26	C
	27	VDOTN= XY / SQRT(XX*YY)
	28	IF (ABS (VDOTN).LT.1.) RETURN
	29	VDOTN= SIGN (1.,VDOTN)
	30	RETURN
	31	100 VDOTN = 0.
	32	RETURN
	33	END