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From: B.Barnes@dcs.warwick.ac.uk (Benjohn Barnes)
Subject: Re: Asynchronous/Random Updating of Cells
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Message-ID: <1995Oct13.144344.20483@dcs.warwick.ac.uk>
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Organization: Department of Computer Science, Warwick University, England
References: <DGBwIK.Etp@aisb.ed.ac.uk> <1995Oct13.130524.15606@dcs.warwick.ac.uk>
Date: Fri, 13 Oct 1995 14:43:44 GMT
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B.Barnes@dcs.warwick.ac.uk (Benjohn Barnes) writes:

>timothyh@aisb.ed.ac.uk (Timothy Hely) writes:

>>Could anyone tell me whether there is a "standard" technique/algorithm
>>for updating a grid of N cells randomly, so that each cell is updated
>>once only before moving on to the next time step.

>Just thought of another way, may be useless though...
>You will have to modify for N where n<>2^i (i an integer)

>Choose i random numbers R1 to Ri.
>for j= 1 to N
> Do (j EOR R1) EOR ((j roled right 1) EOR R2) EOR ... ((j roled right i)
>			EOR Ri)
> Use this number
>next

>role right means shift right and any bits that drop out get put back in at the 
>other end (where the zero's have appered). EG 10010101 roleR 2 is 01100101

>Does this even work ??? I think it would. Also think the numbers should be
>pretty random.

>I may try it, seems quite easy to do, and I'm suposed to be learning c++.
>Oh for BBC BASIC.

>Cheers, 
>	Benjohn


Erm, sorry, this doesn't work atall, but the other does I think. Makes some
interesting sequences though.

Cheers,
	Benjohn
