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From: "cristobal baray" <cbaray@cs.indiana.edu>
Subject: Re: Asynchronous/Random Updating of Cells
Message-ID: <1995Oct17.180946.7585@news.cs.indiana.edu>
Organization: Computer Science, Indiana University
References: <DGBwIK.Etp@aisb.ed.ac.uk> <45p0rc$cq8@gap.cco.caltech.edu>
Date: Tue, 17 Oct 1995 18:09:43 -0500
Lines: 31


I have been looking at the effects of the update rule on CA's.  I have
built this spectrum - can anyone think of additional update rules?

1 - synchronous - uses two arrays for the CA - one is the current time
step, and the other is where t+1 is calcuated.  After all the sites
have been updated (in any order, since the array at time t is not
changed) the array that was t+1 becomes t and t becomes t+1 as we
calculate the next iteration.

2 - wave - uses 1 array for the CA and updates the array from 0..N.

3 - random wave - uses 1 array for the CA.  The site order is shuffled
once before the CA is run, and the CA is updated in that 'random'
order each iteration.

4 - asynchronous without replacement - uses 1 array for the CA.  The
site order is shuffled before each iteration that the CA is run.  Each
site is guaranteed to be updated each iteration.

5 - asychronous with replacement - uses 1 array for the CA.  Each
iteration, N random sites are picked to be updated.  Over T
iterations, each site has been updated approximately T times, although
no site is guaranteed to be updated during any specific iteration.


cristobal baray
cbaray@cs.indiana.edu

-- 
<a href="http://www.cs.indiana.edu/hyplan/cbaray.html">cristobal baray</a>
