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Terminology for pincer patterns without direct deletions

 
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tlanglet



Joined: 17 Oct 2007
Posts: 2461
Location: Northern California Foothills

PostPosted: Sun Jul 25, 2010 9:17 pm    Post subject: Terminology for pincer patterns without direct deletions Reply with quote

I was just playing around and found this ALS_XZ.

Code:
 *-----------------------------------------------------------*
 | 9     3     5     | 2     17    17    | 6     8     4     |
 | 1     6     7     | 4     5     8     | 23    23    9     |
 | 4     8     2     | 36   *36    9     | 5     7     1     |
 |-------------------+-------------------+-------------------|
 | 8     2     13    | 9     17-3  56    | 137   4     56    |
 | 67    9     13    | 57    4     2     | 8    #13    56    |
 | 67    5     4     | 1378  1378  36    | 137   9     2     |
 |-------------------+-------------------+-------------------|
 | 2     7     6     | 135   9     35    | 4    #15    8     |
 | 5     4     9     | 178   1278  17    | 12    6     3     |
 | 3     1     8     | 56   *26    4     | 9    #25    7     |
 *-----------------------------------------------------------*


ALS_XZ (236)r39c5, marked "*" & (1235)r579c8, marked "#".
x=2
z=3

This ALS_XZ does not have any direct deletions. However a little help by transporting does the trick.
(3)r5c8-r5c3=(3)r4c3; r4c5<>3.

So the question is should this situation have a name. ALL wing patterns that do not make a direct deletion are called "flightless". I jokingly called a skyscraper that did not have a direct deletion "grounded" (since a pilot that can't flight is grounded).

But what about other patterns that have pincers that can be transported? Should all be referred to as "flightless" for simplicity?

Note that I have NOT researched this issue. If the sudoku community has already answered this question then I will be happy to follow the standard. If not, I would hope we could define something for this forum.

Ted
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keith



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

PostPosted: Sun Jul 25, 2010 9:35 pm    Post subject: Reply with quote

Ted,

For a number of reasons, I vote for "Flightless" to describe any wing that does not make an immediate deletion, but does make a deletion when a pincer cell is extended by coloring or other means.

I am not aware that the term has been used anywhere but here. I think I coined it, and Nataraj popularized it. I think it is descriptive, and sufficiently whimsical.

We had previously used words like "useless" (the pattern is not useless) and "extended" which has other connotations to some people, or "wing with coloring", which is clumsy.

The point I would make about this kind of terminology, is that it helps with a common language. If you say, "flightless wing", I understand immediately what you mean. If you say "extended wing", it could be a number of things.

Best wishes,

Keith
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tlanglet



Joined: 17 Oct 2007
Posts: 2461
Location: Northern California Foothills

PostPosted: Sun Jul 25, 2010 10:59 pm    Post subject: Reply with quote

Keith,

I agree with your comments but they seem to only address wings. What about other pincer patterns such as the ALS_XZ example, Remote Pairs, etc?

Ted
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keith



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

PostPosted: Mon Jul 26, 2010 1:53 am    Post subject: Reply with quote

Ted,

I'd start with flightless wing, and then see what else may be needed.

I think "flightless" could apply to the extension of any pincer, but I can't really imagine what a flightless remote pair might be.

Best wishes,

Keith
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Jul 26, 2010 2:14 am    Post subject: Reply with quote

There was a time when I thought that I knew the difference between extended and transported. Then I decided that I didn't know the difference and the terminology section of this forum didn't have them defined, either. Flightless falls into the same category. Either you have a working definition for it or you don't. If you do, then it might not match someone else's working definition.

Bottom Line: I'm staying out of making a terminology suggestion on this topic.

What concerns me more is that you turned a 7-cell XY-Chain into an ALS-XY with an extension on one pincer.

Code:
 XY-Chain a-b-c-d-e-f-g  =>  r4c5<>3
 *-----------------------------------------------------------*
 | 9     3     5     | 2     17    17    | 6     8     4     |
 | 1     6     7     | 4     5     8     | 23    23    9     |
 | 4     8     2     | 36   a36    9     | 5     7     1     |
 |-------------------+-------------------+-------------------|
 | 8     2    g13    | 9     17-3  56    | 137   4     56    |
 | 67    9    f13    | 57    4     2     | 8    e13    56    |
 | 67    5     4     | 1378  1378  36    | 137   9     2     |
 |-------------------+-------------------+-------------------|
 | 2     7     6     | 135   9     35    | 4    d15    8     |
 | 5     4     9     | 178   1278  17    | 12    6     3     |
 | 3     1     8     | 56   b26    4     | 9    c25    7     |
 *-----------------------------------------------------------*
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keith



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

PostPosted: Mon Jul 26, 2010 4:03 am    Post subject: Reply with quote

daj95376 wrote:

Bottom Line: I'm staying out of making a terminology suggestion on this topic.


Danny is no Humpty Dumpty:
Quote:
`When I use a word,' Humpty Dumpty said, in rather a scornful tone, `it means just what I choose it to mean -- neither more nor less.'

Laughing
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tlanglet



Joined: 17 Oct 2007
Posts: 2461
Location: Northern California Foothills

PostPosted: Mon Jul 26, 2010 12:33 pm    Post subject: Reply with quote

daj95376 wrote:
What concerns me more is that you turned a 7-cell XY-Chain into an ALS-XY with an extension on one pincer.

Danny,

I am not sure what your concern is about. I was looking for a ALS_XZ and found one, so I posted it as such to frame my question about terminology for pincers without direct deletions. And yes, it turns out to also be a 7-cell xy-chain like many other patterns that can have multiple views.

Would you be more specific about what concerns you?

Ted
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Mon Jul 26, 2010 9:52 pm    Post subject: Reply with quote

tlanglet wrote:
daj95376 wrote:
What concerns me more is that you turned a 7-cell XY-Chain into an ALS-XY with an extension on one pincer.

Would you be more specific about what concerns you?

Don't worry. It's just my OCD opening its big mouth.

Regards, Danny
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tlanglet



Joined: 17 Oct 2007
Posts: 2461
Location: Northern California Foothills

PostPosted: Thu Jul 29, 2010 11:06 pm    Post subject: Reply with quote

I response to the overwhelming interest in this topic, I have decided that I will use the term "flightless" for any pattern that has pincers that do not make a direct deletion, but where deletions are possible by extending/transporting one or both pincers.

It was a long gruesome task but it is great to get it resolved. Wink Wink

Ted
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