POV-Ray : Newsgroups : povray.general : rand question : Re: rand question Server Time
5 Aug 2024 02:16:21 EDT (-0400)
  Re: rand question  
From: Warp
Date: 12 Feb 2003 14:26:24
Message: <3e4a9fe0@news.povray.org>
Vadim Sytnikov <syt### [at] rucom> wrote:
> BTW, in this respect, Knuth was not alone. One of IBM's RNGs (shipped as
> part of FORTRAN libraries for 360's, I believe) appeared to produce series
> that, if interpreted as 3D coordinates, would form points all lying on just
> several planes in 3D space.

  In the man page of rand() in some Unix variant (don't remember which)
there was a note that the lowest bit of the number returned by rand() should
not be used because it alternates between 0 and 1 in successive calls.

  Makes one wonder if it wouldn't be better to fix the problem instead
of documenting it... :)

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -


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