## Sky - Wings (biplane) { Edit: rediscoverd (W-wing)}

Advanced methods and approaches for solving Sudoku puzzles

### Sky - Wings (biplane) { Edit: rediscoverd (W-wing)}

I found this intresting simplistic cycle

...posted this to figure out what it was...

Edit: [yes i know its a xy-chain.] {also called W-wing}(thanks ronk)

that exsits between two pairs

where one set is locked into a house that has two polar opposite end points that are also bivalves

where the end points are identical to each other and not alinged in the same house.

the elimination acts similar to that of a skyscraper.

Code: Select all
` *-----------------------* |. .  .|.  . .| . . .| |X X  X|. AB .|. BC .| |. . BC|. AB .| X X X| *-----------------------* `
=> X <>C

OR

Code: Select all
`|Ab  . .| Ab .   . | . . . ||BC .  .| X   X  X | . . . | |X X X  | BC  .  . | . . . |`
=> X <>C

Code: Select all
` thanks paul for the puzzle!.---------------.-------------.----------------.| 6   18    4   | 3   5  2    | 9    7    18   || 9-5 189   2   | 4   7  18@   | 58@   3    6  || 3   7     58@  | 6   9  18@   | 48-5 14-5 2  |:---------------+-------------+----------------:| 4   2     9   | 5   3  6    | 1    8    7    || 7   5     1   | 2   8  4    | 3    6    9    || 8   6     3   | 7   1  9    | 2    45   45   |:---------------+-------------+----------------:| 2   48    578 | 1   6  578  | 458  9    3    || 1   389   578 | 89  4  3578 | 6    2    58   || 59  3489  6   | 89  2  358  | 7    145  1458 |'---------------'-------------'----------------'`

there is two examples of this function at work:

(5=8)R3C3 - (1|8) R3C6 = (1|8)R2C6 - (8=5)R2C7
=> R2C1, R3C78<>5

OR:

(5=8)R3C3 - (1|8)R1C2 = (1|8)R1C9 - (5=8)R2C7
=> R2C1, R3C78<>5
Last edited by StrmCkr on Thu Feb 26, 2009 3:35 am, edited 7 times in total.
Some do, some teach, the rest look it up.

StrmCkr

Posts: 1134
Joined: 05 September 2006

StrmCkr, it seems you've rediscovered the w-wing. I summarized the w-wing pattern variants here, but don't recall who coined the term.
Last edited by ronk on Wed Feb 25, 2009 2:51 pm, edited 1 time in total.
ronk
2012 Supporter

Posts: 4764
Joined: 02 November 2005
Location: Southeastern USA

i just figured that out befor you wrote the reply ronk.

thanks for the info ronk!

that link will deffintily help me out for varations i never considered befor.

i just finished checking the puzzle on various solvers.

one of them just showed one of the two moves as a W-wing...

(which means its nothing new just something fun!)

http://www.dailysudoku.com/sudoku/forums/viewtopic.php?p=6365&sid=7e86be0928b37fe9a8c75026d9021ec3#6365

Steve R: said it first

I still dont really like the name, it should describe how it looks and acts.

Vote:
rename it to Biplane
(thats how it looks 2 wings. and ellimiantes on two wings...)

or skywings.

learn how to fly you first need 2 wings. :P
Last edited by StrmCkr on Thu Feb 26, 2009 4:21 am, edited 3 times in total.
Some do, some teach, the rest look it up.

StrmCkr

Posts: 1134
Joined: 05 September 2006

Could you add a "NO CHANGE" to the poll ?

... That will give you a more accurate idea.

tarek

tarek

Posts: 3537
Joined: 05 January 2006

Do you want to use the term biplane....

cf swordfish = type of biplane !

C
coloin

Posts: 1877
Joined: 05 May 2005

i know there is biplanes called "sword fish"

but they still only have 2 wings

most notable is the one that crippled the bismarks rudder.

no change - cause its been accepted for a several years now..
Last edited by StrmCkr on Fri Mar 06, 2009 12:10 pm, edited 1 time in total.
Some do, some teach, the rest look it up.

StrmCkr

Posts: 1134
Joined: 05 September 2006

ronk wrote:StrmCkr, it seems you've rediscovered the w-wing. I summarized the w-wing pattern variants here, but don't recall who coined the term.

Here is the history:

http://www.dailysudoku.com/sudoku/forums/viewtopic.php?t=2008

Keith
keith
2017 Supporter

Posts: 216
Joined: 03 April 2006

thanks keith,

i did alot of reading on other sites once i knew what it was called.
i found many threads / topics on the subject.

and found the link above with the first casting of the name "w-wing"

i have also figured out the "remote triple"

thread i have on here is also a varation of the w-wing.
using the properties shown by ronk as an empty rectangle set up.

Code: Select all
`.  .  . |  /  a  / |  .  .  .  . ab  . |  a a-b a |  .  .  .  .  .  . |  /  a  / |  .  .  . ---------+----------+----------  .  .  . |  .  .  . |  .  .  .  . -b  . |  . ab  . |  .  .  .  .  .  . |  .  .  . |  .  .  . ---------+----------+----------  .  .  . |  .  .  . |  .  .  .  .  .  . |  .  .  . |  .  .  .  .  .  . |  .  .  . |  .  .  .  Type E: `
Some do, some teach, the rest look it up.

StrmCkr

Posts: 1134
Joined: 05 September 2006

ronk wrote:I summarized the w-wing pattern variants here ...

To that summary, I've added an example of a W-Ring.
ronk
2012 Supporter

Posts: 4764
Joined: 02 November 2005
Location: Southeastern USA

thanks for the update ronk

i'll have to study those..
Some do, some teach, the rest look it up.

StrmCkr

Posts: 1134
Joined: 05 September 2006