C DETERM    SOURCE    CHAT      05/01/12    22:44:01     5004           
      SUBROUTINE DETERM(AS,ASAC)
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8 (A-H,O-Z)  
C --- CALCUL DU DETERMINANT D'UNE MATRICE 3*3
      DIMENSION AS(3,3)
      ASAC=AS(1,1)*AS(2,2)*AS(3,3)+AS(2,1)*AS(3,2)*AS(1,3)
     &    +AS(3,1)*AS(2,3)*AS(1,2)-AS(1,3)*AS(2,2)*AS(3,1)
     &    -AS(1,2)*AS(2,1)*AS(3,3)-AS(1,1)*AS(3,2)*AS(2,3)
      END