Xref: utzoo comp.sys.mac:55886 comp.sys.mac.programmer:15666 comp.sys.mac.misc:931 comp.sys.mac.system:673
Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!mailrus!wuarchive!zaphod.mps.ohio-state.edu!samsung!uunet!psivax!quad1!ttidca!davidd
From: davidd@ttidca.TTI.COM (David Dantowitz)
Newsgroups: comp.sys.mac,comp.sys.mac.programmer,comp.sys.mac.misc,comp.sys.mac.system
Subject: Re: Random number Generator wanted.
Keywords: Random number
Message-ID: <18200@ttidca.TTI.COM>
Date: 29 Jun 90 19:26:24 GMT
References: <152@asacsg.mh.nl> <1990Jun29.020739.9146@Neon.Stanford.EDU>
Organization: Citicorp/TTI, Santa Monica
Lines: 15

Be quite careful how you splice together random numbers to form larger
random numbers.  Linear-conguential random number generators (of the
form: seed = seed*a mod m + b) have more "random" high order bits than
low order bits.  Appending two 16 bit numbers may skew your
application in a way that's difficult to measure.

If you want a 32 bit random number then check out Knuth for some
multipliers (a) and modulos (m) that will give you "good" random
numbers.  Sorry I don't have it handy.


-- 
David Dantowitz

Singing Barbershop when not computing