      SUBROUTINE DSP(I1,I2,I3,J1,J2,J3,ANG)
      COMMON OV(200,4),CV(200,4),IHKL(200,3),ITITLE(20),
     1A,B,C,AL1,BE1,GA1,GEN(300,3),HKL(300),ICON(10),DTR,RTD
      AL=AL1*DTR
      BE=BE1*DTR
      GA=GA1*DTR
C
C  FLOAT 2 SETS OF HKL'S
C
      ZH = I1
      ZK = I2
      ZL = I3
      CH = J1
      CK = J2
      CL = J3
C
C     CALCULATION OF ANGLE BETWEEN TWO HKL'S.
C
      X=1.-(COS(AL))**2-(COS(BE))**2-(COS(GA))**2
      X=X+2.*(COS(AL))*(COS(BE))*(COS(GA))
      V=A*B*C*SQRT(ABS(X))
      S11=(B*C*SIN(AL))**2
      S22=(A*C*SIN(BE))**2
      S33=(A*B*SIN(GA))**2
      S12=A*B*C**2
      S12=S12*((COS(AL)*COS(BE))-(COS(GA)))
      S23=B*C*A**2
      S23=S23*(COS(BE)*COS(GA)-COS(AL))
      S13=A*C*B**2
      S13=S13*(COS(GA)*COS(AL)-COS(BE))
      ZD=(1.0/V**2)*(S11*ZH**2+S22*ZK**2+S33*ZL**2+2.*S12*
     1ZH*ZK+2.*S23*ZK*ZL+2.*S13*ZH*ZL)
      ZD=SQRT(ABS(1.0/ZD))
      CD=(1.0/V**2)*(S11*CH**2+S22*CK**2+S33*CL**2+2.*S12*
     1CH*CK+2.*S23*CK*CL+2.*S13*CH*CL)
      CD=SQRT(ABS(1.0/CD))
      COSA=(ZD*CD/V**2)*(S11*ZH*CH+S22*ZK*CK+S33*ZL*CL+
     1S23*(ZK*CL+CK*ZL)+S13*(ZL*CH+CL*ZH)+S12*(ZH*CK+
     2CH*ZK))
      IF(COSA.GT.1.0) COSA = 1.0
      ANG = ACOS(COSA)*RTD
      RETURN
      END

