[Tutor] Re: The Game of Life

[Max Noel]

On Jan 6, 2005, at 21:20, Brian van den Broek wrote:

>>     Oh, the Life rules allow a world where every cell will change in 
>> the next generation, iff your world is a torus (i.e. the lower row 
>> "touches" the upper row as if it were immediately above it, and the 
>> right column "touches" the left column as if it were immediately left 
>> of it). It is quite trivial: set all cells to LIVE. Next generation 
>> they're all DEAD.
>
> Topologist! (That's cheating!) ;-)
>
> If we are going that way, you 'iff' seems a bit hasty. Take the 1x1 
> matrix 'full' of live cells.

	Well, if the only cell of a 1x1 torus matrix is LIVE, that  means it 
is surrounded by 4 LIVE cells, doesn't it? :D

> Also, other 'funny' (in the sense that a torus is funny) planes could 
> be defined (say a torus-like structure with more than 1 whole -- 
> cannot recall the general terminology from ill-remembered topology), 
> etc. I meant the claim for a standard non-trivial (i.e. M > 1 and N > 
> 1) MxN euclidean plane matrix, but your correction is both amusing and 
> welcome.

	Thanks :)
	However, the main reason why I talked about a torus is that it's one 
of the two obvious choices when you're implementing Life using a 2D 
matrix (the other being a finite rectangular plane).

-- Max
maxnoel_fr at yahoo dot fr -- ICQ #85274019
"Look at you hacker... A pathetic creature of meat and bone, panting 
and sweating as you run through my corridors... How can you challenge a 
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