Path: utzoo!utgpu!watmath!watdragon!rose!ccplumb From: ccplumb@rose.waterloo.edu (Colin Plumb) Newsgroups: comp.sys.amiga.tech Subject: Re: ARexx psuedo-random number generator Keywords: ARexx Random Number Generator Message-ID: <16646@watdragon.waterloo.edu> Date: 25 Sep 89 03:37:38 GMT References: <19504@unix.cis.pitt.edu> <1989Sep13.032352.10321@agate.berkeley.edu> <12003@cit-vax.Caltech.Edu> <1989Sep22.082034.1405@agate.berkeley.edu> Sender: daemon@watdragon.waterloo.edu Reply-To: ccplumb@rose.waterloo.edu (Colin Plumb) Organization: U. of Waterloo, Ontario Lines: 14 In article <1989Sep22.082034.1405@agate.berkeley.edu> mwm@eris.berkeley.edu (Mike (I'll think of something yet) Meyer) writes: >> A trick recommended by the authors of >> _Numerical Recipes_ (in addition to their own, portable generators) is to >> "scramble " your generator by calling it twice; the first time is >> used as an index to an array of numbers from the generator. > > Knuth recommends a better version of this - use two generators, one > to generate indices, one to generate values. No, if you read Knuth, he says using the same generator is better worst- case and at least as good on average. I happen to like his additive generator (x_n = x_{n-24}+x_{n-55}). -- -Colin