gpamela/gptrd/npoiss.F

*
* $Id$
*
* $Log$
*
*CMZ :  3.00/00 06/04/2001  11.21.19  by  Marialuigia Ambriola
*-- Author :    Marialuigia Ambriola   05/04/2001
      INTEGER FUNCTION NPOISS(X)
**************************************
* Simulate the Poisson distribution
* From data particle book vol. 15 2000
**************************************
      REAL U,A,X
      INTEGER K,N
      NPOISS=0
      K=1
      A=1.
 100  U=RNDM(1)
      A=U*A
      IF(A.LT.EXP(-X)) THEN
         N=K-1
      ELSE
         K=K+1
         GOTO 100
      ENDIF
      NPOISS=N
      RETURN
      END
1	*
2	* $Id$
3	*
4	* $Log$
5	*
6	*CMZ : 3.00/00 06/04/2001 11.21.19 by Marialuigia Ambriola
7	*-- Author : Marialuigia Ambriola 05/04/2001
8	INTEGER FUNCTION NPOISS(X)
9	**************************************
10	* Simulate the Poisson distribution
11	* From data particle book vol. 15 2000
12	**************************************
13	REAL U,A,X
14	INTEGER K,N
15	NPOISS=0
16	K=1
17	A=1.
18	100 U=RNDM(1)
19	A=U*A
20	IF(A.LT.EXP(-X)) THEN
21	N=K-1
22	ELSE
23	K=K+1
24	GOTO 100
25	ENDIF
26	NPOISS=N
27	RETURN
28	END