d4/d41/genexp_8f_source.html

       REAL FUNCTION genexp(av)


 C**********************************************************************

 C

 C     REAL FUNCTION GENEXP( AV )

 C

 C                    GENerate EXPonential random deviate

 C

 C

 C                              Function

 C

 C

 C     Generates a single random deviate from an exponential

 C     distribution with mean AV.

 C

 C

 C                              Arguments

 C

 C

 C     AV --> The mean of the exponential distribution from which

 C            a random deviate is to be generated.

 C                              REAL AV

 C     JJV                      (AV >= 0)

 C

 C     GENEXP <-- The random deviate.

 C                              REAL GENEXP

 C

 C

 C                              Method

 C

 C

 C     Renames SEXPO from TOMS as slightly modified by BWB to use RANF

 C     instead of SUNIF.

 C

 C     For details see:

 C

 C               Ahrens, J.H. and Dieter, U.

 C               Computer Methods for Sampling From the

 C               Exponential and Normal Distributions.

 C               Comm. ACM, 15,10 (Oct. 1972), 873 - 882.

 C

 C**********************************************************************

 C     .. Scalar Arguments ..

       REAL av

 C     ..

 C     .. External Functions ..

       REAL sexpo

       EXTERNAL sexpo

 C     ..

 C     .. Executable Statements ..

 C     JJV added check to ensure AV >= 0.0

       IF (av.GE.0.0) go to 10

       WRITE (*,*) 'AV < 0.0 in GENEXP - ABORT'

       WRITE (*,*) 'Value of AV: ',av

       CALL xstopx('AV < 0.0 in GENEXP - ABORT')


  10   genexp = sexpo()*av

       RETURN


       END

genexp
real function genexp(av)
Definition: genexp.f:1