C CANG      SOURCE    CHAT      05/01/12    21:48:25     5004
      SUBROUTINE CANG(TENS,ANG,YOUN)
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8(A-H,O-Z)
C    Include contenant quelques constantes dont XPI :
-INC CCREEL
      DIMENSION TENS(3)
C
C-------------------------------------------
C     CETTE ROUTINE PERMET DE CALCULER     |
C     L ANGLE DE FISSURATION               |
C-------------------------------------------
C
      ANG=0.D0
      SIREF=YOUN*1.D-4
      B=TENS(3)/SIREF
      A=TENS(1)-TENS(2)
      IF(ABS(B).LE.1.D-10) GOTO 10
      IF(A.EQ.0.D0) THEN
         X=1.D0
         IF(B.LT.0.D0) X=-1.D0
         ANG=X*XPI/4.D0
         GOTO 20
      ENDIF
      ANG=1.D0/2.D0*ATAN(2.D0*TENS(3)/A)
 10   IF(A.LT.0.D0) THEN
         ANG=ANG+XPI/2.D0
      ENDIF
      IF(ANG.GT.(XPI/2.D0)) THEN
         ANG=ANG-XPI
      ENDIF
 20   RETURN
      END