C-----------------------------------------------------------------------
C  Calculate the angle between two Cartesian vectors
C-----------------------------------------------------------------------
      SUBROUTINE ANGL (X1,Y1,Z1,X2,Y2,Z2,ANGLE)
      SPROD = X1*X2 + Y1*Y2 + Z1*Z2
      SMOD = (X1*X1 + Y1*Y1 + Z1*Z1)*(X2*X2 + Y2*Y2 + Z2*Z2)
      COSIN = SPROD/SQRT(SMOD)
      IF (COSIN .GE.  1) COSIN =  1
      IF (COSIN .LT. -1) COSIN = -1
      ANGLE = ACOS(COSIN)
      ANGLE = ANGLE*180/3.141593
      RETURN
      END