Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uwm.edu!ogicse!zephyr.ens.tek.com!uw-beaver!milton!seymour
From: seymour@milton.u.washington.edu (Richard Seymour)
Newsgroups: comp.lang.fortran
Subject: Re: randu?
Message-ID: <17478@milton.u.washington.edu>
Date: 1 Mar 91 21:11:44 GMT
References: <62349@eerie.acsu.Buffalo.EDU> <1991Mar1.010946.16149@sol.UVic.CA>
Organization: University of Washington, Seattle
Lines: 13

haozhou@acsu.buffalo.edu (Hao Zhou) writes:
>>I am trying to port some fortran source code from vax/vms to sun/unix.
>>	call randu(i1,i2,u)
>>where i1,i2,and u weren't initialized before the call. I guess this
>>routine returns a random number in u and i1 and i2 are two seeds.

and i forgot to mention that VMS Fortran predefines all variables to
ZERO, if you don't override it with a data statement
(a consequence of Demand-Zero Virtual memory)

which is why the RANDU routine uses I1=I2=0 as recognition of a initialization.
You can also SET i1 and i2 to zero to replay a random number sequence.
--dick