Path: utzoo!mnetor!tmsoft!torsqnt!jarvis.csri.toronto.edu!rutgers!ucsd!usc!cs.utexas.edu!uunet!mcsun!ukc!dcl-cs!gdt!gdr!exspes
From: exspes@gdr.bath.ac.uk (P E Smee)
Newsgroups: comp.lang.rexx
Subject: Re: Arexx 'random' number generation
Message-ID: <1989Nov16.102415.7663@gdt.bath.ac.uk>
Date: 16 Nov 89 10:24:15 GMT
References: <[255dd53e:14]comp.lang.rexx@tronsbox.UUCP> <89318.193843CMH117@PSUVM.BITNET>
Reply-To: exspes@gdr.bath.ac.uk (P E Smee)
Organization: University of Bristol c/o University of Bath
Lines: 27

In article <89318.193843CMH117@PSUVM.BITNET> CMH117@PSUVM.BITNET (Charles Hannum) writes:
>You are a bonehead.  The first time you call the random number generator,
>(RANDOM), you need to give it a "seed" value as the third argument, otherwise
>you will continue to get the same numbers every time ...

Really?  If so, then Arexx has got it backwards.  In 'proper' REXX (to
quote from the manual)

  [If you specify a seed in the first call] the numbers are generated
  mathematically, using the initial seed, so that as far as possible they
  appear to be random.  Running the program again will produce *the same
  sequence*; using a *different* initial seed will produce a *different*
  sequence.  If you *do not* specify a seed, the first time RANDOM is
  called, the microsecond field of the time-of-day clock will be used as
  the seed; and hence your program will give different results each time
  it is run.

(*'s are mine for emphasis).  If you think about it, it has to be this
way, as otherwise you need a 'metaRandom' function of some sort to
provide an initial seed for your RANDOM function if you want
non-repeating behaviour.

-- 
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