Clouds with p256 glider guns

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skomick
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Joined: February 11th, 2011, 11:41 pm

Clouds with p256 glider guns

Post by skomick » May 7th, 2011, 5:22 pm

Was it Dean Hickerson who created the patterns "life computes pi" and the related pattern "clouds?"

Here are the p256 glider gun versions I created to run fast with Golly's hashlife. I wanted to see more "clouds" faster. I don't know if the p256 version of "life computes pi" actually computes pi, but it's neat to watch in Golly anyway. I've also included the p256 glider gun breeder itself.
p256 Glider Gun Breeder.zip
(190.57 KiB) Downloaded 369 times
The .zip file contains 3 .mc files.
Shannon Omick

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dvgrn
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Re: Clouds with p256 glider guns

Post by dvgrn » May 10th, 2011, 12:19 pm

skomick wrote:Was it Dean Hickerson who created the patterns "life computes pi" and the related pattern "clouds?"
Yes. Here's the original pi-calculating pattern from Hickerson's web page, and the notes on 'Clouds':

http://www.radicaleye.com/DRH/pi.html
http://www.radicaleye.com/DRH/clouds.html
skomick wrote:I don't know if the p256 version of "life computes pi" actually computes pi, but it's neat to watch in Golly anyway.
Sure it does! The breeders still travel at c/2, so the various triangular areas are the same shape as in the original pattern. The only significant difference is the population density in those triangular areas, but that just means you have to use 5/8192 instead of 1/90 in the final formula. The breeders and guns have much higher populations than the original p30 ones, of course, but as the area increases their contribution to the total population becomes negligible.

Here are the adjusted comments for the 'life computes pi p256' pattern:

Code: Select all

#C Population in gen t is asymptotic to  5/65536 (pi-2) t^2.
#C Four p120 breeders move north, east, south, and west.
#C The gliders from each p256 gun run into those from the
#C corresponding gun that's 90 degrees clockwise, in a
#C vanish reaction.  Let T(n) be the triangle with vertices
#C (0,0), (0, t/(2n)), and (t/(2(n+2)), 0).  Within the first
#C quadrant, the gliders occupy, with density 5/8192, the
#C triangle T(1), with the triangle T(3) deleted, with the
#C triangle T(5) added back in, with the triangle T(7)
#C deleted, etc.  Since T(n) has area  t^2/(8n(n+2)) =
#C t^2/16 (1/n - 1/(n+2)),  the occupied area in the
#C first quadrant is
#C
#C     t^2/16 ((1 - 1/3) - (1/3 - 1/5) + (1/5 - 1/7) - ...)  
#C   = t^2/16 (1 - 2/3 + 2/5 - 2/7 + ...)  =  t^2/32 (pi-2).
#C
#C  The same is true of the other quadrants, so the
#C  population converges to 4 * 5/8192 * t^2/32 (pi-2) 
#C    =  5/65536 (pi-2) t^2.

skomick
Posts: 83
Joined: February 11th, 2011, 11:41 pm

Re: Clouds with p256 glider guns

Post by skomick » May 11th, 2011, 2:08 pm

dvgrn wrote:
skomick wrote:I don't know if the p256 version of "life computes pi" actually computes pi, but it's neat to watch in Golly anyway.
Sure it does!
Very nice! Thanks!
Shannon Omick

beebop
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Re: Clouds with p256 glider guns

Post by beebop » October 13th, 2011, 10:32 pm

The link up top is broken.

cloudy197
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Re: Clouds with p256 glider guns

Post by cloudy197 » October 15th, 2011, 11:30 pm

beebop wrote:The link up top is broken.
Try this one.
Attachments
p256 Glider Gun Breeder.zip
(190.57 KiB) Downloaded 288 times

beebop
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Re: Clouds with p256 glider guns

Post by beebop » October 16th, 2011, 12:30 pm

Thanks for the new link.

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