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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: <1995Oct13.130524.15606@dcs.warwick.ac.uk>
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Date: Fri, 13 Oct 1995 13:05:24 GMT
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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
