This commit was generated by cvs2svn to compensate for changes in r2,

[u/mrichter/AliRoot.git] / GEANT321 / gstrag / gdifmg.F

diff --git a/GEANT321/gstrag/gdifmg.F b/GEANT321/gstrag/gdifmg.F
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+*
+* $Id$
+*
+* $Log$
+* Revision 1.1.1.1  1995/10/24 10:21:37  cernlib
+* Geant
+*
+*
+#include "geant321/pilot.h"
+#if defined(CERNLIB_ASHO)
+*CMZ :  3.21/02 29/03/94  15.41.25  by  S.Giani
+*-- Author :
+      SUBROUTINE GDIFMG(DEL)
+ 
+#include "geant321/gccuts.inc"
+#include "geant321/gcasho.inc"
+C-----------------------------------------------------------------------
+C      This program calculates the final distribution coef-
+C      ficients until the integral S is more or equal to L2.
+C      In case of S < L2 or miscalculations due to FORTRAN
+C      limits DONE = FALSE.
+C-----------------------------------------------------------------------
+C      Update history: 10-08-93
+C
+C-----------------------------------------------------------------------
+      REAL BN(50),BNA(50),L2
+      INTEGER FLMAX
+      PARAMETER (DL2=.1)
+      DATA CORMAX/80./
+C-----------------------------------------------------------------------
+C      Initialization steps
+C-----------------------------------------------------------------------
+      XX = 0.
+      Z = 1.
+      DO 10 K=1,NOSC
+         BN(K) = BOSC(K)*IOSC(K)
+         BNA(K) = BN(K)*(AOSC(K) - 1.)
+         XX = XX + AOSC(K)*BOSC(K)
+   10 CONTINUE
+C
+      FLMAX = 0
+      CORR = CORMAX - XX
+      CMGO(1) = EXP(-CORMAX)
+      CMGO(2) = CMGO(1)*BNA(1)
+      Z = Z-(CMGO(1)+CMGO(2))*EXP(CORR)
+C-----------------------------------------------------------------------
+C      Calculation of the current Ci
+C-----------------------------------------------------------------------
+      CALL GRNDM(RNDM,1)
+ 
+      L2 = DL2
+      IF (RNDM.GE.L2) THEN
+         L2 = RNDM
+         FLMAX = 1
+      ENDIF
+      DO 40 NMGO=3,NMGOMA
+         CMGO(NMGO) = CMGO(NMGO - 1)*BNA(1)
+         DO 30 J = 1,NMGO - 2
+            M = NMGO - 1 - J
+            X = BOSC(1)/J
+            DO 20 K=2,NOSC
+               IF(MOD(J+1,IOSC(K)).EQ.0) THEN
+                  L = (J+1)/IOSC(K)
+                  IF(L.EQ.1) THEN
+                     X = X + BNA(K)
+                  ELSE
+                     X = X + BN(K)/(L-1)
+                  ENDIF
+               ENDIF
+   20       CONTINUE
+            CMGO(NMGO) = CMGO(NMGO) + X*CMGO(M)
+   30    CONTINUE
+         CMGO(NMGO) = CMGO(NMGO)/(NMGO-1)
+         Z = Z - CMGO(NMGO)*EXP(CORR)
+         IF (Z.LE.L2) GOTO 50
+   40 CONTINUE
+ 
+   50 IF (FLMAX.EQ.1) THEN
+         DEL = (NMGO-1)*EOSC(1)
+      ELSE
+         DEL = (NMGO-1)*EOSC(1)*L2/RNDM
+      ENDIF
+      IF (DEL.GE.DCUTE*1E6) DEL = DCUTE*1E6
+ 
+      END
+#endif