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Fin terminology

 
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Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Sat Apr 24, 2010 3:29 pm    Post subject: Fin terminology Reply with quote

Folks have been doing some very cool things with almost patterns lately, which is great to see. They've been referred to in different ways, like “almost”, "finned”, “nearly” and so on.

What do y’all think of this approach?

It is well established that the term “fin” is used with fishy patterns like x-wings, swordfish, jellyfish, and bigger fish.

The term “almost” covers non-fishy structures like xy-wings, xyz-wings, you-name-it-wings, locked sets, URs, and on and on. I know one gentleman that can almost a Sue-de-Coq at will, but that’s another story.

To use a term like “finned xy-wing” might cause confusion and has no precedence that I can find. "Almost xy-wing" would be better.

This might seem petty, but most terms come to mean only one thing. If they begin to become widely used to mean something else it dilutes and pollutes the terminology.

I hope I’m not off base and I’m open to suggestions, as always.
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Marty R.



Joined: 12 Feb 2006
Posts: 5180
Location: Rochester, NY, USA

PostPosted: Sat Apr 24, 2010 4:19 pm    Post subject: Reply with quote

Quote:
This might seem petty, but most terms come to mean only one thing.

I think that's true, most terms mean one thing, but that's not mutually exclusive with one thing having more than one term. One example would be Locked Candidates and Box-line interactions meaning the same thing.

A technique I used on the April 24 VH here was 49-48-48-48-89, which performs like an XY-Wing. I call it an XY-Wing Chain (because that's how I learned it), while others call it an Extended XY-Wing, which is a term I've seen used to mean different things.

As to the specific example of Fin, I don't have a problem, as it seems to be used only to describe an extra candidate (occasionally two) without which a standard pattern would exist (e.g., Finned Skyscraper, XY-Wing, Naked Pair, etc.) I interpret Almost to mean the same thing and I haven't had any problems.

That's just how I see it and I don't claim to speak for anyone else.
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Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Sat Apr 24, 2010 4:45 pm    Post subject: Reply with quote

Marty R. wrote:
As to the specific example of Fin, I don't have a problem, as it seems to be used only to describe an extra candidate (occasionally two) without which a standard pattern would exist (e.g., Finned Skyscraper, XY-Wing, Naked Pair, etc.) I interpret Almost to mean the same thing and I haven't had any problems.

That the two terms are being used interchangeably is the problem. I invite you to follow this link to Sudopedia and tell me it doesn't smell like fish in there Smile .

While you're there, do a search for "fin" if you'd like.
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ttt



Joined: 06 Dec 2008
Posts: 42
Location: vietnam

PostPosted: Sun Apr 25, 2010 9:02 am    Post subject: Re: Fin terminology Reply with quote

Luke451 wrote:
To use a term like “finned xy-wing” might cause confusion and has no precedence that I can find. "Almost xy-wing" would be better.

Yes, I’m not good on using terminologies (by some reasons... Very Happy). So IMO, the “Almost” term is easy for me... Very Happy

For example:

Code:
 *--------------------------------------------------------------------*
 | 189    13789  378    | 19     4      2      | 3689   5689   35689  |
 | 469    349    346    | 59     359    8      | 1      2      7      |
 | 189    2      5      | 6      1379   379    | 4      89     389    |
 |----------------------+----------------------+----------------------|
 | 3      6      478    | 2      789    479    | 789    15     15     |
 | 4589   45789  1      | 4789   36789  34679  | 2      6789   689    |
 | 289    789    278    | 1789   16789  5      | 6789   3      4      |
 |----------------------+----------------------+----------------------|
 | 268    38     2368   | 789    6789   1      | 5      4      3689   |
 | 7      1458   9      | 3      568    46     | 68     168    2      |
 | 14568  13458  3468   | 4589   2      469    | 36789  16789  13689  |
 *--------------------------------------------------------------------*

Present as diagram: => r5c6<>6

Code:
Almost XY-wing(3689)r35c9/r1c7
 ||
(XY-wing:368)r35c9/r1c7-(6)r6c7=(6)r5c89
 ||
(9)r35c9-(9)r79c9=(9)r9c78-(9=46)r89c6
 ||
(89)r1c7/r3c8-(89=3)r3c9-(3)r3c6=(3)r5c6

Tri-sis based on pattern XY-wing that combines bi-value (89)r3c8 and ALS(469)r89c6...

For hard puzzles (SE rating >=9.0) IMO, based on bi-value cells then we can be found some “Almost” patterns like XY-wing, XYZ-wing... and combine with A*ALSs or candidtes on row/col/box.

ttt
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Mogulmeister



Joined: 03 May 2007
Posts: 695

PostPosted: Sat May 01, 2010 10:44 pm    Post subject: Re: Fin terminology Reply with quote

Luke451 wrote:
Folks have been doing some very cool things with almost patterns lately, which is great to see. They've been referred to in different ways, like “almost”, "finned”, “nearly” and so on.

What do y’all think of this approach?

It is well established that the term “fin” is used with fishy patterns like x-wings, swordfish, jellyfish, and bigger fish.

The term “almost” covers non-fishy structures like xy-wings, xyz-wings, you-name-it-wings, locked sets, URs, and on and on. I know one gentleman that can almost a Sue-de-Coq at will, but that’s another story.

To use a term like “finned xy-wing” might cause confusion and has no precedence that I can find. "Almost xy-wing" would be better.

This might seem petty, but most terms come to mean only one thing. If they begin to become widely used to mean something else it dilutes and pollutes the terminology.

I hope I’m not off base and I’m open to suggestions, as always.


My two Euros worth:

I think that it is always usage that governs the application of language and subsequent terminology. Even a "wrong" word can become current and mean something which it strictly doesn't. Orthodoxy in nomenclature often battles with semantics and these do not always make good bedfellows.

The French and Chinese have been building walls to try and protect their languages from "pollution" by English. We the English have tried and failed to build walls against Americanisms. Neologisms rise and fall by usage. They gain traction that way and in the end definitions loose meaning as usage wins out.

So, "fish" were used because of some convenient shapes and many arguments ensued as various marine exotica were used. Some of Havard's early forums solicited Marine terms to describe ever larger
structures eg

http://www.sudoku.frihost.net/forum/viewtopic.php?t=990&

Since when was an x-wing a "fish" ?

Then "fins" were used to describe extensions or extra candidates as people tried to stick with pelagic terminology. There's sashimi and if you look hard enough someone probably has bento box but it hasn't made the light of day due to lack of use.

A "fin" is an excresence, a protruding aquatic body part, an "extra" in an otherwise ordered grid. Equally, the presence of an extra candidate can make something "almost".

Got to say that I don't really mind - since I left this board last time we now have pincers (but where are the crabs/lobsters etc?) that "transport". Fair enough, left to my British sensibilities I'd probably have used "extension" but if everyone starts transporting, so will I.

Got to say I agree with Marty - the alternative is go with someone like Bill Richter (sp?) who has his own (as far as my small brain can tell) classification system.

Either way it will all "evolve" in the same way that English does - just don't get me on the subject of modern solecisms.
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Luke451



Joined: 20 Apr 2008
Posts: 310
Location: Southern Northern California

PostPosted: Sun May 02, 2010 3:53 pm    Post subject: Reply with quote

Mogulmeister wrote:
Since when was an x-wing a "fish" ?

Since when hasn't it?

The first line from Sudopedia: "An X-Wing is a fish pattern involving 2 rows and 2 columns."

Fish have fins. That's why sudoku fish have fins, sticking with the pelagic theme, as you say. One can find an almost finned fish. Are we to start in with finned finned fish now? (I can hear it already: "Why the heck not? We already have "almost almost locked sets! ") Smile

I agree that language is in a constant state of flux and yesterday bad meant bad, but today bad means good. However, beyond this board no one's seeing fins on anything but fish.
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Sun May 02, 2010 6:51 pm    Post subject: Re: Fin terminology Reply with quote

Mogulmeister wrote:
Some of Havard's early forums solicited Marine terms to describe ever larger structures

Thanks for providing the name Leviathan Exclamation ___ I've needed it a few times. As in ...

Code:
 +-----------------------+
 | . . 2 | 3 . 9 | 1 5 . |
 | . . . | 2 . . | . . 6 |
 | 9 . 4 | . . 6 | . . . |
 |-------+-------+-------|
 | 2 6 . | 5 . 4 | 3 . . |
 | . . . | . 2 . | . . . |
 | 5 . 3 | 1 . . | . . . |
 |-------+-------+-------|
 | 3 . . | 4 . . | . 1 5 |
 | 8 . . | . . . | 6 . . |
 | . 2 . | . . . | 4 . 3 |
 +-----------------------+   # P_Set_D:  8

 +--------------------------------------------------------------------------------+
 |  6       78      2       |  3       478     9       |  1       5       478     |
 |  17      3       18      |  2       4578    578     |  789     489     6       |
 |  9       5       4       |  78      1       6       |  278     3       278     |
 |--------------------------+--------------------------+--------------------------|
 |  2       6       789     |  5       789     4       |  3       789     1       |
 |  4       1       789     |  6789    2       3       |  5       6789    789     |
 |  5       789     3       |  1       6789    78      |  2789    246789  24789   |
 |--------------------------+--------------------------+--------------------------|
 |  3       79      679     |  4       6789    2       |  789     1       5       |
 |  8       4       15      |  79      3       15      |  6       279     279     |
 |  17      2       1569    |  6789    56789   1578    |  4       789     3       |
 +--------------------------------------------------------------------------------+

Leviathan r1458c16b7\r2c2389b5+r9|c5|b8  <> 7  [r9c5]
Leviathan r1458c1b27\r2c234589           <> 7  [r9c5]
Leviathan r18c167b47\r26c23b39+r9|c5|b8  <> 7  [r9c5]
Leviathan r18c16b467\r26c2389 +r9|c5|b8  <> 7  [r9c5]


BTW, all of Havard's fish elimination examples can be derived through the smaller "finned Franken Swordfish".
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wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Mon May 03, 2010 1:19 am    Post subject: Re: Fin terminology Reply with quote

daj95376 wrote:


BTW, all of Havard's fish elimination examples can be derived through the smaller "finned Franken Swordfish".


Tiny hiss fit, Havard is my longest mentor. I attribute to him most of my understanding. Danny, you are next.
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keith



Joined: 19 Sep 2005
Posts: 3184
Location: near Detroit, Michigan, USA

PostPosted: Mon May 03, 2010 2:11 am    Post subject: Re: Fin terminology Reply with quote

wapati wrote:
... Havard is my longest mentor. I attribute to him most of my understanding. Danny, you are next.


Interesting thought.

First of all, I learned the Sudoku basics by using Sudoku Susser and by studying Robert Woodhead's excellent solution manual. That was years ago, but I still cannot think of a better place to start.

Next, all the contributors to this, the DailySudoku forum, who have asked questions and posted interesting puzzles and solutions, have greatly expanded my understanding. MartyR is at the top of that list.

Havard's "Two Strong Links" was a revelation for me.

After that, TKiel, Myth Jellies, ravel, re'born, Mike Barker, Ronk, Ruud, and others helped me along.

At the risk of offending those not named, nataraj and Danny have been great fun these last couple of years.

Keith

(Don't criticize my list: Post your own!)
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wapati



Joined: 10 Jun 2008
Posts: 472
Location: Brampton, Ontario, Canada.

PostPosted: Mon May 03, 2010 3:35 am    Post subject: Re: Fin terminology Reply with quote

keith wrote:

(Don't criticize my list: Post your own!)
Quite so.
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon May 03, 2010 7:25 am    Post subject: Reply with quote

And Jeff.

With my special thanks to Angus Johnson for writing Simple Sudoku and making it freeware. Without it, I never would have examined/studied so many scenarios and had Idea happen nearly as often.
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Mogulmeister



Joined: 03 May 2007
Posts: 695

PostPosted: Mon May 03, 2010 8:57 pm    Post subject: Reply with quote

Luke451 wrote:
Mogulmeister wrote:
Since when was an x-wing a "fish" ?

Since when hasn't it?

The first line from Sudopedia: "An X-Wing is a fish pattern involving 2 rows and 2 columns." Is that Leviticus or John ?

Fish have fins. That's why sudoku fish have fins, sticking with the pelagic theme, as you say. One can find an almost finned fish. Are we to start in with finned finned fish now? (I can hear it already: "Why the heck not? We already have "almost almost locked sets! ") Smile

I agree that language is in a constant state of flux and yesterday bad meant bad, but today bad means good. However, beyond this board no one's seeing fins on anything but fish.


I was being semantic on the fish - all the others are indeed fish but X-wing sounds more like a aero fighter!

I believe fin will evolve in its own way as did American English (and English English for that matter). If we stop and think about it a second, a finned x-wing presents loads of inate contradictions for both structural and physiological reasons but because people use it so do I.

A fin is often a generalised excresence, a torpedo has fins so do old rockets and according to that other "bible" (wiki) "has been extended to include other animal limbs and man-made devices"

If a "man-made device" like a sudoku structure has a "fin" and its not attached to a fish then so what ? The extension of the word fin to non "fish" is directly analogous to the extension, usage and assimilation of many other words.

However. we could go down another path and call the "almost thing" that sticks out of a recognised but "non fish" pattern - a "tumour" perhaps? Laughing

Quote:
However, beyond this board no one's seeing fins on anything but fish.


Who knows for sure ? Whether or not people do or don't use terminology beyond this forum now really won't matter, usage will however - I remember some of the "Wings" evolving (w&m) for example and I seem to remember one of them perhaps started here (George Woods?). Is it Ayers Rock or Uluru ? Is it speciality or specialty ? I could go on but mercifully shan't. Smile


Last edited by Mogulmeister on Tue May 04, 2010 5:49 am; edited 2 times in total
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Mogulmeister



Joined: 03 May 2007
Posts: 695

PostPosted: Mon May 03, 2010 9:09 pm    Post subject: Reply with quote

Thanks Danny for the name recognition! I suspect that a Leviathan, like the real thing is exceedingly rare but many thanks for showing me one !!!!Smile
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