C DECOUP    SOURCE    CHAT      05/01/12    22:39:27     5004           
C  CALCUL AUTOMATIQUE DES DECOUPAGES
C
      SUBROUTINE DECOUP(INBR,DEN1,DEN2,APROG,NBELEM,DENI,DECA,DLONG)
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8 (A-H,O-Z)
      IF (INBR.GT.0) GOTO 100
      XAUX=abs(((DEN1-DEN2)**2)/2)
      IF (DEN2.LT.DEN1) APROG=1+XAUX-SQRT(XAUX*(2+XAUX))
      IF (DEN2.GE.DEN1) APROG=1+XAUX+SQRT(XAUX*(2+XAUX))
      IF (ABS(APROG-1).GT.1.D-5) GOTO 20
      XNBELE=1.D0/DEN1
      NBELEM=INT(XNBELE)
      NBELEM=MAX(1,NBELEM)
      IF (XNBELE/NBELEM.GT.(NBELEM+1)/XNBELE) NBELEM=NBELEM+1
      IF (INBR.LT.0) NBELEM=-INBR
      DEN1=1.D0/DBLE(NBELEM)
      GOTO 21
  20  CONTINUE
      XNBELE=(LOG(DEN2/DEN1)/LOG(APROG))
      NBELEM=INT(XNBELE)
      NBELEM=MAX(1,NBELEM)
      IF (XNBELE/NBELEM.GT.(NBELEM+1)/XNBELE) NBELEM=NBELEM+1
      IF (INBR.LT.0) NBELEM=-INBR
  21  CONTINUE
      IF (ABS(APROG-1).GT.1.D-5) 
     $     DEN1=(1-APROG)/((1-APROG**NBELEM)*APROG)
      DENI=DEN1*DLONG
      DECA=(DEN2-DEN1)*DLONG
      GOTO 101
 100  APROG=1.D0
      NBELEM=INBR
      DEN1=1.D0/INBR
      DENI=DLONG/INBR
      DECA=0
 101  CONTINUE
      RETURN
      END