Reviewing Special:RecentChanges

[confocaloid]

https://conwaylife.com/w/index.php?diff ... did=102873
My guess is that the intent was to replace "fraction" ==> "number":
>> "to move at any speed that is a rational number lower than c/4"

https://en.wikipedia.org/wiki/Rational_number

Edit by Sokwe: I reworded that sentence a bit to match an earlier sentence about the 2c/9-limit form.

[DroneBetter]

edit by Haycat2009 to Grin reagent changed "iteration" to "tick," with description "use less jargon"

this is a change that conflicts with existing conventions and should be reverted, right?
according to Wiktionary, a tick is

wiktionary[/url]](computing) A jiffy (unit of time defined by basic timer frequency).

and whereas this is sometimes used in a broader context to mean the same thing as iteration (from what I know, commonly in Minecraft redstone circuitry terminology, being the indivisible unit by which time proceeds)
Life is an abstract thing independent of computer implementation

[Sokwe]

edit by Haycat2009 to Grin reagent changed "iteration" to "tick," with description "use less jargon"

The standard term is "generation". "Tick" typically also means "generation" in this context, but "iteration" does not, so I think Haycat2009 was right to change it; however, I think "generation" is the better choice, so I've changed it again.

Edit: by the way, grin reagent was found by Dean Hickerson on April 20, 1997.

[confocaloid]

edit by Haycat2009 to Grin reagent changed "iteration" to "tick," with description "use less jargon"

The standard term is "generation". "Tick" typically also means "generation" in this context, but "iteration" does not, so I think Haycat2009 was right to change it; however, I think "generation" is the better choice, so I've changed it again.
[...]

I believe the two terms have different meanings. In my understanding, in Life/CA-related discussions the word 'tick' usually refers to a step between two generations of a pattern (for example, going from a phase of an oscillator to the next phase), while the word 'generation' usually refers to just one phase. For example, 'the generation T = 0', 'the tick from T = 0 to T = 1'.

[dvgrn]

I believe the two terms have different meanings. In my understanding, in Life/CA-related discussions the word 'tick' usually refers to a step between two generations of a pattern (for example, going from a phase of an oscillator to the next phase), while the word 'generation' usually refers to just one phase. For example, 'the generation T = 0', 'the tick from T = 0 to T = 1'.

Are there any example uses that bear out either of those examples? I can't think where to look for someone saying "the generation T = 0" -- just plain "At T = 0" seems much more common.

"The tick from T = 0 to T = 1" doesn't seem like familiar usage, either; seems like someone might describe what happens "between T = 0 and T = 1", but the unit of Life-universe time between T = 0 and T = 1 could equally well be referred to as a "generation" or a "tick", as far as I can see.

The Life Lexicon says just

":tick = generation"

and

":generation The fundamental unit of time. The starting pattern is generation 0."

That does seem like an interesting usage difference, come to think of it -- the "T =" part doesn't get used if "generation" is included, but people do say "generation {N}" a lot more often than they say "tick {N}"... whereas it's probably more common to say "on the next tick" than "on/in the next generation", maybe because "tick" is such a nice short word.

EDIT: The question of whether or not "tick" and "generation" are synonyms ... doesn't seem to need another post from me, since no editing questions hinge on it at the moment. I'll just add a few links here in case there's further discussion in the future: it looks to me more like "tick" and "generation" are synonyms, but that "tick" is more commonly used in some situations and "generation" is more commonly used in other situations.

Usually if "generation" is used in a situation where "tick" is more common, it's readily understood and no one complains that the term is being misused -- example 1, example 2, example 3. Substitutions in the other direction also happen without confusion or objection, though maybe that's even rarer -- example 4 -- possibly partly because the "T = {N}" syntax attracts anyone who might want to say "tick {N}" in place of "generation {N}".

[confocaloid]

I believe the two terms have different meanings. In my understanding, in Life/CA-related discussions the word 'tick' usually refers to a step between two generations of a pattern (for example, going from a phase of an oscillator to the next phase), while the word 'generation' usually refers to just one phase. For example, 'the generation T = 0', 'the tick from T = 0 to T = 1'.

Are there any example uses that bear out either of those examples? [...]

I posted those specific examples to illustrate the difference between meanings. Here are some previous examples from forum posts by others (I quoted parts that contain forms of words 'tick' and 'generation'):

[...] Obviously, the eight-tick predecessor that I found would be extremely unlikely to actually occur, but even the six-tick predecessor looks mostly decent, and some variations of that six-cell predecessor that also work, such as 5bo$2bo$b4o$o$b2o$2b2o$4bo2bo$5bobo, look very plausible. Even the seven-tick predecessor bears a strong resemblance to generation thirteen of the B-heptomino, so it's possible that this can be made in a similar way, although getting around the tub could be tricky.

[...] Here is a version that has the same population and lasts for two generations longer: [...]

[...]

1279-tick 15x14 diehard: [...]
1281-tick 16x16 diehard: [...]
1761-tick 32x32 symmetric diehard: [...]
16x16 52514M, one generation better than the current record-holder: [...]

A two-glider octomino has 41 matches in the 12x12-1G-octohash database, its child and grandchild having 125 and 148 respectively. The count of results keeps increasing, as expected when evolving the input pattern further, and for the 28-tick descendant it reaches 281.

However, from generation 145 on, the count starts to decrease, and at 251 it drops to 0. This means that there is no 12x12-1G-octohash result for the octomino ash (constellation xp2_yj2552z696ycezy0888y41110s0111zw70ggg07yh696zzybg8gzyb121).

A similar trend is also found on the following evolutionary sequence with a 673-tick lifespan, but not on pi-heptomino or lumps of muck:

Code: Select all

x = 5, y = 4, rule = B3/S23
4bo$o2bo$obo$3o!

Why?

Even though Life Lexicon claims 'tick = generation', I believe the two words are usually used in different ways. There's a useful distinction between (a) some generation (a pattern) versus (b) evolving that pattern for one tick to reach the next generation.

[confocaloid]

Not Life related/Public tape speedy deletion (content/activity that doesn't fall in LifeWiki scope).

https://conwaylife.com/w/index.php?diff ... did=137691 (edit summary) "Races" like that don't feel like a particularly good idea. That increases likelihood of errors due to extra unnecessary speed, and it becomes hard to review recent changes due to high volume.

[unname4798]

Not Life related/Public tape speedy deletion (content/activity that doesn't fall in LifeWiki scope).

https://conwaylife.com/w/index.php?diff ... did=137691 (edit summary) "Races" like that don't feel like a particularly good idea. That increases likelihood of errors due to extra unnecessary speed, and it becomes hard to review recent changes due to high volume.

You didn't read the notice!

[confocaloid]

Spartan G-to-W-to-H (permanent link)

• Several added patterns don't show the output (which on LifeWiki is normally done using a ghost Herschel). Below are replacement versions of the patterns, with a ghost Herschel added.
• In the pattern with appended F166, the intended meaning of the caption should be clarified.
  The caption claims "no FNG issues", which is a bit misleading, because the first natural glider of the output Herschel will damage the conduit unless something is done to prevent that. The part "no FNG issues" would be more honest (albeit still vague) if the FNG of the output Herschel could escape freely without damaging the conduit.
• The first occurrence of 'Spartan' in article text should be wikilinked, and all occurrences should be uppercased for consistency.
  In third paragraph ("The Glider-to-wing can only be connected to..."), 'Glider' should be changed to 'glider'.
• In the viewer "...this uses an eater 5 instead of a welded still life...", the enforced HTML linebreak is unnecessary and should be removed from the caption.
  Instead of adding enforced linebreaks (which don't work consistently because readers have different devices / browsers / fonts), the width of the embedded viewers should be reduced (change the 'style' parameter value to 'width:300px;').
• All zoom values in viewers should be changed to even integer numbers.

Code: Select all

#C infobox
x = 38, y = 33, rule = B3/S23
12b2o$13bo6b2o$13bobo4b2o$14b2o$10bo$4bo5b3o$4b3o6bo$o6bo4b2o$b2o3b2o
27bo$2o33bo$24b2o9b3o$24b2o11bo7$14b2o$14b2o9b2o$25bobo$2b2o23bo$bobo
23b2o$bo$2o4b2o$7bo$4b3o$4bo16b2o$21bobo$14b2o7bo$15bo7b2o$12b3o$12bo!

Code: Select all

#C "more complicated still life" -- where this pattern comes from?
x = 38, y = 33, rule = B3/S23
12b2o$13bo6b2o$13bobo4b2o$14b2o$10bo$4bo5b3o$4b3o6bo$o6bo4b2o$b2o3b2o
27bo$2o33bo$24b2o9b3o$24b2o11bo4$36b2o$32bo3b2o$31bobo$14b2o14bobo$14b
2o9b2o3bo$25bobob2o$2b2o23bobo$bobo23bobo$bo26bo$2o4b2o$7bo$4b3o$4bo
16b2o$21bobo$14b2o7bo$15bo7b2o$12b3o$12bo!

Code: Select all

#C with appended F166
x = 87, y = 33, rule = B3/S23
12b2o$13bo6b2o$13bobo4b2o45bo$14b2o49b3o$10bo53bo$4bo5b3o51b2o$4b3o6bo
$7bo4b2o$2bo3b2o27bo$obo32bo$b2o21b2o9b3ob2o$24b2o11bob2o26b2o15bo$67b
2o15bo$84b3o$86bo4$14b2o$14b2o9b2o9b2o$25bobo7bobo$2b2o23bo7bo26b2o$bo
bo23b2o5b2o26b2o$bo$2o4b2o$7bo40b2o$4b3o42bo$4bo16b2o23b3o$21bobo22bo$
14b2o7bo34b2o$15bo7b2o33bo$12b3o44b3o$12bo48bo!

[confocaloid]

https://conwaylife.com/w/index.php?diff ... did=142707 Bad formatting (ZOOM not set to an even integer value; width too high - should be reduced to 300px or so); lack of a forum link to substantiate the claim that the shown oscillator is a SKOP.

https://conwaylife.com/w/index.php?diff ... did=130492 Too short displayed link text (related discussion) and an incorrect link; should be changed to {{slcells|11|text=11-bit}}
https://conwaylife.com/w/index.php?diff ... did=130447 Same issues as above; should be changed to {{slcells|10|text=10-bit}}
https://conwaylife.com/w/index.php?diff ... did=130368 Same issues as above; should be changed to {{slcells|12|text=12-bit}} Additionally, long^6 should be changed to long{{sup|6}} and likewise for long^3.
https://conwaylife.com/w/index.php?diff ... did=145332 Same as above.
https://conwaylife.com/w/index.php?diff ... did=142328 Same as above.

Some previously posted issues still remain unresolved, in particular

Multiple issues [...]
Reposting previous unresolved issues [...]

Spartan G-to-W-to-H (permanent link) [...]

EDIT by dvgrn: Top six links taken care of (by Chris857).

[confocaloid]

There are many recent low-quality edits, including edits mentioned above. It would be nice to make sure that those changes are corrected, and that any further changes of the same kind will not have to be fixed again for the same reasons.

https://conwaylife.com/w/index.php?diff ... did=150082 Too short displayed link text and vague wording. Should be either changed to "The resulting oscillator has minimum population {{cells|42|text=42 alive cells}}", or possibly the sentence removed completely (why it is even relevant in that context what's the minimum population of the oscillator?)

[...] Too short displayed link text (related discussion) [...]
[...]
Some previously posted issues still remain unresolved

EDIT by dvgrn: I've asked Haycat2009 to look over these recent suggestions, and fix what needs to be fixed, and learn what can be learned. A quick response came back, but this was likely toward the end of Haycat2009's day, so the improvement process has started with this Pentoad edit but will likely continue tomorrow.

@confocaloid, can you please try to find a way to word these suggestions that comes across as less rude? Your term "low-quality" seems unnecessary here. To me, a lot of these edits seem to fall into the category "could be standardized a little more". I.e., it's not that the changes themselves are a bad idea. They don't need to be rolled back, because they're an improvement; they just need a little more improvement to line up better with the "best practice" way these templates are used elsewhere.

[confocaloid]

The edit https://conwaylife.com/w/index.php?diff ... did=122129 replaced a synthesis forum reference from 2020 with a different reference from 2024. I think the old reference(s) should be kept in the article. The aim of a "Glider synthesis" section is to document subsequent improvements (history of reductions); removing old links undermines that goal.

Without changes to the displayed text, one way to keep old footnotes is as follows:

Code: Select all

The cost has since been reduced several times,<ref name="post102367" /> most recently to {{gliders|11|text=11 gliders}} by [[Goldtiger997]] on June 26, {{year|2024}}.<ref name="post188666" />

with cleanup by moving the rest of the markup into the "References" section.

Further cleanup in the same page:

• "rulespecial" can be removed per https://conwaylife.com/w/index.php?oldi ... _parameter
• viewers configuration fails to specify an even integer ZOOM value, leading to inferior display

EDIT by dvgrn: Done, mostly by Chris857. The "has been reduced several times" was my wording from a while back, because this spaceship has a long and rather convoluted history of reductions. The history is documented in the "How about a crab synthesis?" thread that the article links to. For some of the incremental reductions, I think the total cost in gliders was never actually worked out before the next reduction came along.

[confocaloid]

https://conwaylife.com/w/index.php?diff ... did=150204
There is a mismatch between the added claim "It can be infinitely extended.", the edit summary "Add fact that it is agar", and the caption previously saying "p47 B-heptomino hassler" with the viewer showing a (finite) oscillator.

When one is talking about extensibility of an oscillator, it makes sense to say that it can be arbitrarily extended (while still remaining finite). It is incorrect to say "infinitely" in this context.

An agar is an infinite (either stable or periodic) pattern, repeating both in space and in time.

Additionally, an explanation is missing for how exactly the oscillator can be arbitrarily extended (although a forum post linked elsewhere from the same page provides some hints).

[confocaloid]

https://conwaylife.com/w/index.php?diff ... did=138466
The removal is incorrect. Just because the p101 might no longer be a SKOP, doesn't invalidate that it was a SKOP. It is still true, and it will always be true, that discovering NW-2T16 led to a new p101 SKOP.

EDIT by dvgrn: The removal has been undone. DroneBetter's edit summary in adding the Catagolue links specifically suggested that the SKOPs might be superseded some day.

[confocaloid]

https://conwaylife.com/w/index.php?diff ... did=141667

The edit adds links to an old quote. The links are to much newer (and problematic) attempts at definitions, which didn't exist in 1994.

I believe the edit should be rolled back. The wiki should never attempt to do "mind reading" by ascribing newer meanings to words and phrases in old quotes.

[dvgrn]

https://conwaylife.com/w/index.php?diff ... did=141667

The edit adds links to an old quote. The links are to much newer (and problematic) attempts at definitions, which didn't exist in 1994.

I believe the edit should be rolled back. The wiki should never attempt to do "mind reading" by ascribing newer meanings to words and phrases in old quotes.

I added those links, because those uses of "transition" and "transition table" are actually very nice clear examples from 1994, of the exact same meanings of "transition" and "transition table" that I've documented in the transition (Rule definition) LifeWiki page.

Unname4798 has now rolled back those added links, citing confocaloid's objection.

Not surprisingly -- given that I made that edit in the first place! -- it doesn't seem to me that confocaloid's objection is valid in any way. Clearly "transition table" was a term that existed in 1994, since Robert Andreen was using it -- and I think that I've explained it reasonably accurately in the article I linked to. I'm going to generalize that explanation slightly now, as I had already done in the Transition_(disambiguation) definition, so that it isn't necessarily specific to Golly transition tables.

Similarly, the "transition" term that I added the link to equally clearly means a piece of a transition table -- not anything like "an ordered pair (current cellstate, new cellstate)". That 1994 use of "transition" matches the commonly used technical definition of "transition" that confocaloid wants to remove from the LifeWiki -- and it doesn't at all match the old LIFELINE definition that confocaloid claims is intuitive and self-explaining.

Now, I wouldn't be surprised if someone could improve the article to explain things better or more succinctly, though! Succinctness has never exactly been my strong point. Just please be careful not to try to make over the "Transition (rule definition)" article to talk about the "ordered pair (current cellstate, new cellstate)" definition of the term. That article is supposed to explain the particular sense of "transition" that Robert Andreen used in that 1994 quote.

To me, all of this suggests that it's a (minor) improvement to the article to add a link to explain what "transition table" and "transition" are intended to mean in that context. Why would newcomers not be potentially confused, when as far back as 1994 "transition" is clearly sometimes being used to mean a piece of a transition table, and sometimes it means an actual change from oldstate to newstate? The link can help make the distinction between those two perfectly valid uses of "transition", by guiding a reader to the correct definition for that context.

Please, no edit wars needed!
Anyone who disagrees with unname4798's undo of my change should please not go and change it back on the LifeWiki right away! It's not an important enough change that it's even slightly important whether the links are in that quote in that article right now or not.

However, I'm very interested to hear what other people think about the validity of those links! So if you're reading this and have an opinion about those links -- either that they don't belong there or that they do -- please consider writing something here to say what your opinion is.

For reference, here's the full relevant quote including the links that I added (EDIT: with the "transition table" link a little higher up than it was before):

[…] The real difficulty lies in *visualizing* what you are doing when you change values in the tables and drawing inferences about what values to change to produce what results. […] a strategy might be as follows. From randomized transition tables with random initial configurations, look for `interesting' small scale structures, such as gliders, blinkers, quasars, rotators, etc. Isolate these structures and analytically or experimentally determine their minimal transition tables, ie, the array of *necessary* transitions to produce the structure along with indications of the "Don't Care" transitions. Repeat until you have a decent library of these tables in a database. Now automate a search, compare and integrate process that will combine compatible transition tables. Investigate these new transition tables with random initial configurations. At a minimum, all compatible structures will be preserved and there will be the possibility of new, perhaps more complex structures. Isolate them and repeat the process until, at a limit, all "Don't Care" transitions are filled. This is more or less what I do, but I really haven't thought out the automated part of it. […]

[confocaloid]

https://conwaylife.com/w/index.php?diff ... did=141667

The edit adds links to an old quote. The links are to much newer (and problematic) attempts at definitions, which didn't exist in 1994.

I believe the edit should be rolled back. The wiki should never attempt to do "mind reading" by ascribing newer meanings to words and phrases in old quotes.

I added those links, because those uses of "transition" and "transition table" are actually very nice clear examples from 1994, of the exact same meanings of "transition" and "transition table" that I've documented in the transition (Rule definition) LifeWiki page.

I disagree. Those uses of those phrases aren't examples of "the exact same meanings" that you have "documented" (with that word in quotes).

When Andreen discussed "the "Don't Care" transitions", they didn't really talk about "The elementary unit of a cellular-automaton rule definition" (whatever that is).
Andreen didn't really talk about "lines of Golly rule tables" (or lines of any ruletable, for that matter).
Andreen definitely didn't talk about dvgrn's ridiculous misinterpretation of calcyman's forum post.

[...]That 1994 use of "transition" matches the commonly used technical definition of "transition" that confocaloid wants to remove from the LifeWiki -- and it doesn't at all match the old LIFELINE definition that confocaloid claims is intuitive and self-explaining. [...]

That means you failed to understand the quote that you're attempting to "explain" by inserting your links.

The quote from 1994 uses the word 'transition' with the exact meaning from Lifeline. A transition tells the current state of a cell and the new state of the same cell. Nothing more.
An array of transitions specifies, for every possible value of the neighbourhood function, the current state of the cell and the new state of the same cell.
Per the source of the quote ( https://web.archive.org/web/19990224055 ... /0007.html ):

[...] Then a convenient way of describing the next state of any cell can be found using a `transition table' where the current states and the neighborhood function are plotted against each other to determine a cell's new state which appear in the body of the table, as below, with k possible states:
[...]
Calling F() the 8sum, Life is completely described by the transition table below:

Code: Select all

8sum
\ 0 1 2 3 4 5 6 7 8
|--------------------------
Center 0 | 0 0 0 1 0 0 0 0 0
Cell 1 | 0 0 1 1 0 0 0 0 0

Other `Life'-like CA's can be developed by changing the pattern of 0's and 1's in the table. Try putting 1's at 0: 6,7, e.g. [...]

[...] Just please be careful not to try to make over the "Transition (rule definition)" article to talk about the "ordered pair (current cellstate, new cellstate)" definition of the term. That article is supposed to explain the particular sense of "transition" that Robert Andreen used in that 1994 quote.

As explained above, Andreen's text from 1994 uses the word 'transition' with the meaning equivalent to an ordered pair of the current cellstate and the state of the same cell in the next generation. You misinterpreted the quote.

[dvgrn]

That means you failed to understand the quote that you're attempting to "explain" by inserting your links.

The quote from 1994 uses the word 'transition' with the exact meaning from Lifeline. A transition tells the current state of a cell and the new state of the same cell. Nothing more.

Sorry, confocaloid, it's not as simple as that.

When Andreen says "*necessary* transitions", the meaning isn't "the necessary subset of [0 -> 0], [0 -> 1], [1, 0], [1, 1]" -- which are all the possible transitions in a two-state rule, according to the definition of "transition" that you've been insisting on lately. Try to interpret that quote in that way and you end up with a statement that doesn't make any sense.

Andreen is talking about [0 -> 0], [0 -> 1], [1, 0], or [1, 1] in particular positions in the transition table that he's talking about.

Any particular position in the table, in combination with the value found there, has a precise one-to-one correspondence with the "B0" through "B8" and "S0" through "S8" transitions that my writeup discusses. Not B0-8 and S0-8 conditions, mind you -- definitely transitions (specifying both the neighbor-population condition and the current and future states of the key cell).

[confocaloid]

That means you failed to understand the quote that you're attempting to "explain" by inserting your links.

The quote from 1994 uses the word 'transition' with the exact meaning from Lifeline. A transition tells the current state of a cell and the new state of the same cell. Nothing more.

[...] Andreen is talking about [0 -> 0], [0 -> 1], [1, 0], or [1, 1] in particular positions in the transition table that he's talking about. [...]

Which is why it is called 'transition table'.

A transition table is an array of transitions. Each entry of that array is a transition; i.e., an element of the four-element set { birth 0 -> 1, death 1 -> 0, survival 1 -> 1, absence of birth 0 -> 0 }.

An entry of the transition table doesn't itself "know" the conditions under which it happens or doesn't happen. That isn't specified in the transition. That depends on the position of the entry within the array.

Again, I believe that you completely misinterpreted the quote that you are attempting to "explain".

[dvgrn]

Which is why it is called 'transition table'.

A transition table is an array of transitions. Each entry of that array is a transition; i.e., an element of the four-element set { birth 0 -> 1, death 1 -> 0, survival 1 -> 1, absence of birth 0 -> 0 }.

An entry of the transition table doesn't itself "know" the conditions under which it happens or doesn't happen. That isn't specified in the transition. That depends on the position of the entry within the array.

Again, I believe that you completely misinterpreted the quote that you are attempting to "explain".

Well, I've looked things over carefully, one more time. I can't say as I agree with your last paragraph. I mostly agree with your first three paragraphs, but your conclusions don't follow from those statements. Things continue to be just a little bit more subtle than you seem to believe.

Here's one key point: your statement

"Each entry of that array is a transition; i.e., an element of the four-element set { birth 0 -> 1, death 1 -> 0, survival 1 -> 1, absence of birth 0 -> 0 }."

is perfectly understandable -- but it's technically incorrect. If you look at each entry of that array, it's a single digit -- "0" or "1". One single bit of information is not a transition in either the LIFELINE sense or in the transition (rule definition) sense.

I completely agree with you that if you pay attention to just the information in the row headers -- center cell = 0 for the first row of the transition table, and center cell = 1 for the second row -- then each entry of that array obviously implies a LIFELINE-transition (and nothing more). You get the oldstate "0" or "1" from the row header, and the newstate from the array entry.

So far so good. The entries themselves aren't LIFELINE-transitions, but together with row header information, they imply LIFELINE-transitions.

However, you haven't given any reason why the row headers in that table are important, and yet the column headers somehow should be completely ignored. To enable your interpretation that each array entry is a LIFELINE-transition and "nothing more", you have to arbitrarily ignore the information provided by the column headers.

Conversely, if you pay attention to the information from both the row headers and the column headers, then there's a very clear simple one-to-one correspondence between the eighteen entries in the table and the eighteen standard rule-definition transitions -- B0 through B8 and S0 through S8.

Testing out the terminology

Your claim that "The quote from 1994 uses the word 'transition' with the exact meaning from Lifeline" simply doesn't hold up at all, as far as I can see.

Please try using Andreen's phrases in an explanatory sentence yourself, talking about let's say a figure-eight oscillator. Use Andreen's phrases "necessary transitions" and "Don't Care transitions", but somehow make it so that the meaning of "transition" is limited to the old LIFELINE definition.

When Andreen talks about "necessary transitions" and "Don't Care transitions", he really doesn't seem to be referring to simple LIFELINE-transitions that are nothing more than ordered pairs of cell states. He's talking about specific positions in his transition tables -- which imply neighbor-count information along with the oldstate and newstate.

Here's how a discussion of a figure-eight oscillator comes out using the conwaylife community's current standard usage of "transition":

A figure eight has necessary transitions B3, S2, and S3, and Don't Care transitions B7, B8, and S7. A figure eight doesn't work if any of the necessary transitions are removed -- but it does continue to work just fine if some or all of the Don't Care transitions are added.

That's exactly the kind of analysis that Andreen was talking about. It seems to me that Andreen's use of "transition" absolutely requires the concept that we now call a "transition" -- the neighborhood conditions combined with oldstate->newstate ordered pairs that are implied by his tables.

Andreen suggests recording the "necessary" and "Don't Care" information in the form of one of his transition tables -- like this for a figure-eight oscillator:

Code: Select all

8sum
\ 0 1 2 3 4 5 6 7 8
|--------------------------
Center 0 | 0 0 0 1 0 0 0 DON'T-CARE DON'T-CARE
Cell 1 | 0 0 1 1 0 0 0 DON'T-CARE 0

That's workable, but quite hard to read compared to the standard terminology we're using these days. We can track that same information a lot more succinctly with a minrule-maxrule rule range, as we do in the figure-eight article:

"B3/S23 – B378/S237".

[confocaloid]

Note: two cellstates (dead/off/0 and alive/on/1), square grid, and range-1 Moore neighbourhood are assumed in most of the discussion.

[...] the conwaylife community's current standard usage [...]

I think it is counterproductive to attempt to declare any "standard usage". There is no "standard usage" in the local community on this website, because there is no reliable, commonly agreed, uncontroversial way to determine what counts as "standard".

It would be much more productive to aim for intuitive, self-explanatory terminology that is easy to understand and hard to misunderstand.
Existing usage of words and phrases in the local community is frequently counterintuitive or self-contradictory.

[...]
Andreen suggests recording the necessary and don't-care information in the form of one of his transition tables -- like this for a figure-eight oscillator:

Code: Select all

8sum
\ 0 1 2 3 4 5 6 7 8
|--------------------------
Center 0 | 0 0 0 1 0 0 0 DON'T-CARE DON'T-CARE
Cell 1 | 0 0 1 1 0 0 0 DON'T-CARE 0

That's workable, but quite hard to read compared to the standard terminology we're using these days. We can track that same information a lot more succinctly with a minrule-maxrule rule range, as we do in the figure-eight article:

"B3/S23 – B378/S237".

I disagree. Transition tables are more illuminating and helpful. They highlight the existing possibilities explicitly, instead of packing them into a "rulestring gibberish" (which is basically how newcomers see most rulestring notations). A table is easier to read, easier to understand, and easier to derive further information of interest.

It should be obvious that "easy to write" doesn't imply "easy to read".

[...] if you pay attention to just the information in the row headers -- center cell = 0 for the first row of the transition table, and center cell = 1 for the second row -- then each entry of that array obviously implies a LIFELINE-transition (and nothing more). You get the oldstate "0" or "1" from the row header, and the newstate from the array entry.

So far so good. The entries themselves aren't LIFELINE-transitions, but together with row header information, they imply LIFELINE-transitions. [...]

Within a transition table of the kind given in the message by Andreen, every single entry is a choice between either specifying one of two possible cellstate-to-cellstate transitions for that entry, or leaving the transition unspecified ("Don't Care").

If you consider only specific cellular automata (rather than minimal transition tables of structures), then for every fully specified condition, there are exactly two possible choices of the transition that is prescribed to happen whenever that condition is met:

• If the fully specified condition tells that "the" cell is currently dead, then the transition happening in that case can be either Birth or Abstain. It's impossible to prescribe either Survival or Death in this case.
• If the fully specified condition tells that "the" cell is currently alive, then the transition happening in that case can be either Survival or Death. It's impossible to prescribe either Birth or Abstain in this case.

There is a correspondence between positions in the transition table array and fully specified conditions available in the rulespace. 18 entries, 18 fully specified conditions. 102 entries, 102 fully specified conditions. 512 entries, 512 fully specified conditions.

There is a correspondence between allowed values of an entry in the transition table array and transitions that can be prescribed to happen. Specifying '0' or '1' in an entry specifies which of two state-to-state transitions happens (under the condition determined by the position of that entry). It's either "birth vs. abstain" choice, or "survival vs. death" choice.

For that reason, it feels quite intuitive and natural to interpret those "single bits" as cellstate-to-cellstate transitions, in the sense consistent with Lifeline: https://conwaylife.com/w/index.php?oldid=126314#Page_2

Those "single bits" aren't rules. Changing a single entry in the table changes what happens (the transition) without changing when it happens (the condition).

[...] Andreen's phrases "necessary transitions" and "Don't Care transitions" [...]

[...] When Andreen talks about "necessary transitions" and "Don't Care transitions", he really doesn't seem to be referring to simple LIFELINE-transitions that are nothing more than ordered pairs of cell states. He's talking about specific positions in his transition tables -- which imply neighbor-count information along with the oldstate and newstate. [...]

I believe your interpretation is incorrect.
"Don't Care" means "don't care what happens if such-and-such condition is met", rather than "don't care what is the condition".

When Andreen talks about "necessary transitions" and "Don't Care transitions", they are referring to specific values in the array entries, rather than to positions.

A necessary transition corresponds to a value that has to remain unchanged, for the structure of interest to evolve in the same way.
A "Don't Care" transition corresponds to a value that can be changed, without affecting the evolution of the structure of interest.
Changing the value in an entry doesn't affect where the entry is located within the array.

Here is a quote from the 1994 source:

[...] Isolate these structures and analytically or experimentally determine their minimal transition tables, ie, the array of *necessary* transitions to produce the structure along with indications of the "Don't Care" transitions. [...]

For the figure eight oscillator to work unchanged, it doesn't matter whether the rules prescribe the transition "birth" or the transition "abstain" when the condition B8/A8 is met. That condition is never queried during evolution of the structure of interest. The corresponding entry in the transition table array is never read:

Code: Select all

x = 6, y = 6, rule = B38/S23
3o$3o$3o$3b3o$3b3o$3b3o!

The transition table for Conway's Life specifies the transition 0 -> 0 "abstain" for the condition B8/A8 "a dead cell with eight alive neighbours".
The minimal transition table for the figure eight oscillator specifies 0 -> ? "Don't Care" for the same condition B8/A8.

For the figure eight oscillator to work unchanged, the rules must prescribe the transition "death" when the condition S8/D8 is met.
Ironically, prescribing the transition "survival" instead leads to the structure failing to survive:

Code: Select all

x = 6, y = 6, rule = B3/S238
3o$3o$3o$3b3o$3b3o$3b3o!

Both the transition table for Conway's Life, and the minimal transition table for the figure eight oscillator, specify the transition 1 -> 0 "death" for the condition S8/D8 "an alive cell with eight alive neighbours".

A figure eight has "necessary transitions" B3, S2, and S3, and "Don't Care transitions" B7, B8, and S7. A figure eight doesn't work if any of the necessary transitions are removed -- but it does continue to work just fine if the Don't-Care transitions are added.

I think your invented example is nonsensical.

It is incompatible with Andreen's usage, because Andreen refers to state-to-state transitions. Neither of B3, S2, S3, B7, B8, S7 you listed is a transition. Those abbreviations can be read as referring to transition rules.

"Don't Care transitions" are state-to-state transitions that are left unspecified in some entries of the minimal transition table for the oscillator (rather than rules like B7, B8, S7).

The figure eight oscillator is an object ("structure"). Transition rules belong to the ruleset, rather than to the object. The figure eight oscillator doesn't "have" any rules.

It is impossible to "add" or "remove" a rule. One cannot "add" the S3 rule when there is already the D3 rule; instead, one can replace the rule D3 by the rule S3. All four possible transitions are relevant to determining the minimal transition table of an object. In addition to specifying required/optional "birth" and "survival" transitions, one has to specify required/optional "abstain" and "death" transitions in the table as well.

[squareroot12621]

...

[...]
Andreen suggests recording the necessary and don't-care information in the form of one of his transition tables -- like this for a figure-eight oscillator:

Code: Select all

8sum
\ 0 1 2 3 4 5 6 7 8
|--------------------------
Center 0 | 0 0 0 1 0 0 0 DON'T-CARE DON'T-CARE
Cell 1 | 0 0 1 1 0 0 0 DON'T-CARE 0

That's workable, but quite hard to read compared to the standard terminology we're using these days. We can track that same information a lot more succinctly with a minrule-maxrule rule range, as we do in the figure-eight article:

"B3/S23 – B378/S237".

I disagree. Transition tables are more illuminating and helpful. They highlight the existing possibilities explicitly, instead of packing them into a "rulestring gibberish" (which is basically how newcomers see most rulestring notations). A table is easier to read, easier to understand, and easier to derive further information of interest.

It should be obvious that "easy to write" doesn't imply "easy to read".
...
There is a correspondence between positions in the transition table array and fully specified conditions available in the rulespace. 18 entries, 18 fully specified conditions. 102 entries, 102 fully specified conditions. 512 entries, 512 fully specified conditions.
...

What if you want to write an isotropic transition table? I don't think you'd want to have to write something like this:

Code: Select all

B3-jky/S2-e3acinq – B2ci34cikqtyz5-k6-n78/S234-jknqr5-aci6-e7

                             |
                             |
                             V

Neighbors  0_ 1c 1e 2a 2c 2e 2i 2k 2n 3a 3c 3e 3i 3j 3k 3n 3q 3r 3y 4a 4c 4e 4i 4j 4k 4n 4q 4r 4t 4w 4y 4z 5a 5c 5e 5i 5j 5k 5n 5q 5r 5y 6a 6c 6e 6i 6k 6n 7c 7e 8_
Center Off 0  0  0  0  ?  0  ?  0  0  1  1  1  1  ?  ?  1  1  1  ?  0  ?  0  ?  0  ?  0  ?  0  ?  0  ?  ?  ?  ?  ?  ?  ?  0  ?  ?  ?  ?  ?  ?  ?  ?  ?  0  ?  ?  ?
Center On  0  0  0  1  1  ?  1  1  1  1  1  ?  1  ?  ?  1  1  ?  ?  ?  ?  ?  ?  0  0  0  0  0  ?  ?  ?  ?  0  0  ?  0  ?  ?  ?  ?  ?  ?  ?  ?  0  ?  ?  ?  ?  ?  0

(I probably got some of that wrong anyway.)
I'd rather have something that's slightly hard to read than something that doesn't fit in the infobox.

[confocaloid]

[...] It should be obvious that "easy to write" doesn't imply "easy to read". [...]

What if you want to write an isotropic transition table? I don't think you'd want to have to write something like this: [...]
I'd rather have something that's slightly hard to read than something that doesn't fit in the infobox.

With 102 isotropic conditions, a full "minimal transition table" of some "structure" (object) could still be reasonably small to fit on a page. It doesn't have to be compact, and it doesn't have to be written manually; it can be autogenerated.

In the two-state R1 Moore INT rulespace, the minimal transition table of some oscillator or spaceship could be formatted like this (note that I just reformatted the table from your post):

Code: Select all

-------------------------------------------------------------------
Neighbors  0_ 1c 1e 2a 2c 2e 2i 2k 2n 3a 3c 3e 3i 3j 3k 3n 3q 3r 3y
Center Off  0  0  0  0  ?  0  ?  0  0  1  1  1  1  ?  ?  1  1  1  ?
Center On   0  0  0  1  1  ?  1  1  1  1  1  ?  1  ?  ?  1  1  ?  ?
-------------------------------------------------------------------
Neighbors  4a 4c 4e 4i 4j 4k 4n 4q 4r 4t 4w 4y 4z
Center Off  0  ?  0  ?  0  ?  0  ?  0  ?  0  ?  ?
Center On   ?  ?  ?  ?  0  0  0  0  0  ?  ?  ?  ?
-------------------------------------------------------------------
Neighbors  5a 5c 5e 5i 5j 5k 5n 5q 5r 5y 6a 6c 6e 6i 6k 6n 7c 7e 8_
Center Off  ?  ?  ?  ?  ?  0  ?  ?  ?  ?  ?  ?  ?  ?  ?  0  ?  ?  ?
Center On   0  0  ?  0  ?  ?  ?  ?  ?  ?  ?  ?  0  ?  ?  ?  ?  ?  0
-------------------------------------------------------------------

The transition table of some cellular automaton (chosen from the same rulespace) could look the same way, except without any question marks.

My point is that I believe such tables are significantly easier to read and understand (compared to many rulestring notations), and it is easier to extract information from them. (For example, if there are n cellstates and m question marks in the "minimal transition table", then the object works in n^m different cellular automata from the rulespace. Every question mark denotes a possible choice between n different state-to-state transitions that can be prescribed to happen whenever the corresponding condition is met, and there are m independent choices.)

See also relevant discussion in the section "Formatting the General Symmetric Moore Neighborhood" in Andreen's 1994 message.

[confocaloid]

[...] low-effort low-contribution activity [...]

Some relatively recent wiki edits:

https://conwaylife.com/w/index.php?diff ... did=150739 The word "bun" should remain lowercased, shouldn't be uppercased. EDIT by dvgrn: Rolled back by Unname4798.

https://conwaylife.com/w/index.php?diff ... did=150911 Nonconstructive changes in the userspace of another user. (Replacing a Golly-supported, Golly-canonical rulestring with a Golly-unsupported rulestring.)
Any unwelcome edits in someone else's userspace can and should be rolled back. EDIT by dvgrn: Rolled back by Unname4798.

https://conwaylife.com/w/index.php?diff ... did=150897 "Semi-stable" is ill-defined. EDIT by dvgrn: Rolled back by Unname4798.

https://conwaylife.com/w/index.php?diff ... did=131083 Adding claims about usage of 'overclocking' without any supporting evidence to back up those claims. EDIT by dvgrn: Rolled back by Haycat2009.

https://conwaylife.com/w/index.php?diff ... did=150914 Incorrect revert of an edit that was an improvement. The p160 oscillator in question is not a "reflectorless rotating oscillator" in a useful sense, and it isn't loopable, but it is definitely rotating (period 160, mod 40). See viewtopic.php?p=190392#p190392 EDIT by dvgrn: Rolled back by Unname4798.

https://conwaylife.com/w/index.php?diff ... did=125212 Missing discovery information / links to relevant discussion. See discussion in Thread for basic questions: viewtopic.php?p=190351#p190351 EDIT by dvgrn: I've added one link to the relevant discussion thread; more could be done here.

[Sokwe]

You've added new pages for several spaceships of questionable notability (e.g., 41P4H1V0, 51P5H2V0.1, p8 swan tagalong‎‎). Do these have a particular purpose?