Talk:Elementary cellular automaton/Random number generator: Difference between revisions

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The description urges "little endian" (byte order in longer integer types), but was really talking about arranging bits in a byte. Misnomer? --[[User:Ledrug|Ledrug]] ([[User talk:Ledrug|talk]]) 18:54, 20 March 2014 (UTC)
The description urges "little endian" (byte order in longer integer types), but was really talking about arranging bits in a byte. Misnomer? --[[User:Ledrug|Ledrug]] ([[User talk:Ledrug|talk]]) 18:54, 20 March 2014 (UTC)

:It seems so. My bad. Is "with the least significant bit at the end" correct?--[[User:Grondilu|Grondilu]] ([[User talk:Grondilu|talk]]) 09:55, 21 March 2014 (UTC)

:: Yeah, or "most significant bit first". --[[User:Ledrug|Ledrug]] ([[User talk:Ledrug|talk]]) 17:47, 21 March 2014 (UTC)


==Probably needs more restrictions==
==Probably needs more restrictions==
Rule 30 with fixed '0' ends just goes to '1' in all cells after a while. --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 06:33, 21 March 2014 (UTC)
Rule 30 with fixed '0' ends just goes to '1' in all cells after a while. --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 06:33, 21 March 2014 (UTC)

:Have you tried with many different array sizes?--[[User:Grondilu|Grondilu]] ([[User talk:Grondilu|talk]]) 09:56, 21 March 2014 (UTC)

::100 (as used in Perl),and also 10. I think it may be down to me using fixed '0' boundaries but this is allowed in the Eca task? --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 14:04, 21 March 2014 (UTC)

:::If you can confirm that with fixed boundary states, all ECA converge towards a finite state of "all 1" for any array size, then indeed it might be better to enforce warping arrays.--[[User:Grondilu|Grondilu]] ([[User talk:Grondilu|talk]]) 20:04, 21 March 2014 (UTC)

:::: It took me more than a few moments to discover that &nbsp; '''eca''' &nbsp; stood for &nbsp; <big>''<u>e</u>lementary <u>c</u>elluar <u>a</u>utomation''</big>. &nbsp; &nbsp; -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 20:10, 28 July 2019 (UTC)

::I can confirm that for 100 and 10 it does go to 1's for column that starts with a 1 in it doing Rule 30. Seems to me that you can't do [[Elementary cellular automaton]] and this task without making the former more specidic? What did you do with boundaries for your solution that works? --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 23:26, 21 March 2014 (UTC)

:::I did wrap them, as I found it much easier to implement. I will narrow the requirement in the parent task.--[[User:Grondilu|Grondilu]] ([[User talk:Grondilu|talk]]) 02:24, 22 March 2014 (UTC)

::::Thanks Grondilu :-) <br> --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 07:34, 22 March 2014 (UTC)

==C Entry==
Perhaps the C entry is performing some undefined behavour (out-of-bound shifts at run-time, found statically with the D compiler):
<lang C>for (state = i = 0; i < N; i++)
if (rule & B(7 & (st>>(i-1) | st<<(N+1-i))))
</lang>

Latest revision as of 01:48, 24 July 2022

Endianness or MSB/LSB difference?

The description urges "little endian" (byte order in longer integer types), but was really talking about arranging bits in a byte. Misnomer? --Ledrug (talk) 18:54, 20 March 2014 (UTC)

It seems so. My bad. Is "with the least significant bit at the end" correct?--Grondilu (talk) 09:55, 21 March 2014 (UTC)
Yeah, or "most significant bit first". --Ledrug (talk) 17:47, 21 March 2014 (UTC)

Probably needs more restrictions

Rule 30 with fixed '0' ends just goes to '1' in all cells after a while. --Paddy3118 (talk) 06:33, 21 March 2014 (UTC)

Have you tried with many different array sizes?--Grondilu (talk) 09:56, 21 March 2014 (UTC)
100 (as used in Perl),and also 10. I think it may be down to me using fixed '0' boundaries but this is allowed in the Eca task? --Paddy3118 (talk) 14:04, 21 March 2014 (UTC)
If you can confirm that with fixed boundary states, all ECA converge towards a finite state of "all 1" for any array size, then indeed it might be better to enforce warping arrays.--Grondilu (talk) 20:04, 21 March 2014 (UTC)
It took me more than a few moments to discover that   eca   stood for   elementary celluar automation.     -- Gerard Schildberger (talk) 20:10, 28 July 2019 (UTC)
I can confirm that for 100 and 10 it does go to 1's for column that starts with a 1 in it doing Rule 30. Seems to me that you can't do Elementary cellular automaton and this task without making the former more specidic? What did you do with boundaries for your solution that works? --Paddy3118 (talk) 23:26, 21 March 2014 (UTC)
I did wrap them, as I found it much easier to implement. I will narrow the requirement in the parent task.--Grondilu (talk) 02:24, 22 March 2014 (UTC)
Thanks Grondilu :-)
--Paddy3118 (talk) 07:34, 22 March 2014 (UTC)

C Entry

Perhaps the C entry is performing some undefined behavour (out-of-bound shifts at run-time, found statically with the D compiler): <lang C>for (state = i = 0; i < N; i++) 

   if (rule & B(7 & (st>>(i-1) | st<<(N+1-i))))

</lang>

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