C-----------------------------------------------------------------------
C  Decide on the crystal system based on the cell edges and angles
C-----------------------------------------------------------------------
      SUBROUTINE ANGSYS (ABC,SANG,CANG,ISYS)
      DIMENSION ABC(3),SANG(3),CANG(3),ANG(3)
      EQUIVALENCE (ABC(1),A), (ABC(2),B), (ABC(3),C),
     $            (ANG(1),AL),(ANG(2),BE),(ANG(3),GA)
      DATA RA/57.2958/,TAN/0.1/,TED/0.01/
C-----------------------------------------------------------------------
C  Make the angles from their sines and cosines
C-----------------------------------------------------------------------
      DO 100 I = 1,3
        ANG(I) = RA*ATAN2(SANG(I),CANG(I))
  100 CONTINUE
      ISYS = 0
      IF (AMOD(AL - BE) .GT. TAN) THEN
C-----------------------------------------------------------------------
C  Monoclinic or triclinic ?
C-----------------------------------------------------------------------
        IF (AMOD(AL - GA) .GT. TAN) THEN
C-----------------------------------------------------------------------
C  Triclinic
C-----------------------------------------------------------------------
          ISYS = 1
        ELSE
C-----------------------------------------------------------------------
C  Monoclinic
C-----------------------------------------------------------------------
          ISYS = 2
        ENDIF
      ELSE
C-----------------------------------------------------------------------
C  Cubic, rhombohedral, hexagonal, tetragonal, or orthorhombic
C-----------------------------------------------------------------------
        IF (AMOD(AL - GA) .GT. TAN) THEN
C-----------------------------------------------------------------------
C  Hexagonal
C-----------------------------------------------------------------------
          ISYS = 5
        ELSE
          IF(AMOD(AL - 90.0) .GT. TAN) THEN
C-----------------------------------------------------------------------
C  Rhombohedral
C-----------------------------------------------------------------------
            ISYS = 6
          ELSE
            IF (AMOD(A - B) .GT. TED) THEN
C-----------------------------------------------------------------------
C  Orthorhombic
C-----------------------------------------------------------------------
              ISYS = 3
            ELSE
              IF (AMOD(B - C) .GT. TED) THEN
C-----------------------------------------------------------------------
C  Tetragonal
C-----------------------------------------------------------------------
                ISYS = 4
C-----------------------------------------------------------------------
C  Cubic
C-----------------------------------------------------------------------
              ELSE
                ISYS = 7
              ENDIF
            ENDIF
          ENDIF
        ENDIF
      ENDIF
C-----------------------------------------------------------------------
C  Just in case !!
C-----------------------------------------------------------------------
      IF (ISYS .EQ. 0) ISYS = 1
      RETURN
      END