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XYZ technique

 
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dldcamp



Joined: 29 May 2007
Posts: 15
Location: Florida

PostPosted: Wed Aug 05, 2009 3:11 pm    Post subject: XYZ technique Reply with quote

Why do some XYZ choices work and others don't? My friend and I each do the very hard daily puzzles together but separately. We each do our own puzzle in other words.... Yesterday I did an XYZ and the puzzle finished correctly very quickly. She did a different one and where she erased a six according to the XYZ that's where my six went! So if she would have continued with the puzzle, she would have not been able to finish it. She is discouraged because she has a difficult time finding XYZ possibilities and thought this was one and I looked at it and it should have been one. I don't get it and don't know what to tell her.
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Kdelle



Joined: 20 Mar 2008
Posts: 59
Location: Hudson, NH

PostPosted: Wed Aug 05, 2009 3:41 pm    Post subject: Reply with quote

My understanding of the XYZ wing is that XYZ must share a Box with either XY or YZ and must also "see" the other. Elimination of Y can be made only in a cell that "sees" all three.

Someone please correct me if this is not correct. Thanks.

Kathy
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arkietech



Joined: 31 Jul 2008
Posts: 1729
Location: Northwest Arkansas USA

PostPosted: Wed Aug 05, 2009 7:16 pm    Post subject: Reply with quote

My understanding is you can only remove candidates from the two cells that "see" all three of the components of the xyz wing.
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Thu Aug 06, 2009 7:14 am    Post subject: Reply with quote

1) An XYZ-Wing must occur in a chute (band or stack).

2) The XYZ cell is called the pivot/vertex, and the XY & YZ cells are called pincer cells.

3a) The pincer cells can not see each other.

3b) One pincer cell must be in the same box as the XYZ cell.

3c) The other pincer cell must be in the same row/column as the XYZ cell, but not in the same box.

4) Eliminations occur inside the (3b) box where it intersects the row/column used in (3c).

Here's an example in [band 1].

Code:
 +-----------------------------------------------+
 |  -Y  -Y  XYZ  |   .   .   .   |   .   YZ  .   |
 |   .   .   .   |   .   .   .   |   .   .   .   |
 |  XY   .   .   |   .   .   .   |   .   .   .   |
 |---------------+---------------+---------------|
 |   .   .   .   |   .   .   .   |   .   .   .   |
 |   .   .   .   |   .   .   .   |   .   .   .   |
 |   .   .   .   |   .   .   .   |   .   .   .   |
 |---------------+---------------+---------------|
 |   .   .   .   |   .   .   .   |   .   .   .   |
 |   .   .   .   |   .   .   .   |   .   .   .   |
 |   .   .   .   |   .   .   .   |   .   .   .   |
 +-----------------------------------------------+
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dldcamp



Joined: 29 May 2007
Posts: 15
Location: Florida

PostPosted: Tue Aug 11, 2009 10:17 pm    Post subject: Reply with quote

Thanks, this explains it simply!
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storm_norm



Joined: 18 Oct 2007
Posts: 1741

PostPosted: Sat Aug 29, 2009 12:46 am    Post subject: Reply with quote

I'd just like to add that a xyz-wing can exist in one house like a column or row except we don't call it a xyz-wing, we call it a naked triple.
this is a naked triple

Code:
+----------+-------+---------+
| . 56  57 | . . . | . 567 . |
| . .  .   | . . . | . .   . |
| . .  .   | . . . | . .   . |
+----------+-------+---------+


then here is the naked triple bent into the xyz-wing.

Code:
+--------+-------+----------+
| . 56 . | . . . | .  567 . |
| . .  . | . . . | 57 .   . |
| . .  . | . . . | .  .   . |
+--------+-------+----------+


also,
a xy-wing is just a naked triple bent into another house.
here is the classic naked triple.

Code:
+---------+-------+--------+
| . 56 57 | . . . | . 67 . |
| . .  .  | . . . | . .  . |
| . .  .  | . . . | . .  . |
+---------+-------+--------+


then here is the naked triple bent into a xy-wing

Code:
+--------+-------+---------+
| . 56 . | . . . | .  67 . |
| . .  . | . . . | 57 .  . |
| . .  . | . . . | .  .  . |
+--------+-------+---------+

-------
the other naked trip in a house is
Code:
+-------+-------+------------+
| . . . | . . . | 567 567 56 |
| . . . | . . . | .   .   .  |
| . . . | . . . | .   .   .  |
+-------+-------+------------+
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strmckr



Joined: 18 Aug 2009
Posts: 61

PostPosted: Sat Aug 29, 2009 3:19 am    Post subject: Reply with quote

ive modified storms and added in the eliminations with each type.

Code:
 naked triple: x <> 567
+----------+-------+---------+
| x 56  57 | x x x | x 567 x |
| . .  .   | . . . | . .   . |
| . .  .   | . . . | . .   . |
+----------+-------+---------+


Code:
 xyz-wing x <> 5
+--------+-------+----------+
| . 56 . | . . . | x  567 x |
| . .  . | . . . | 57 .   . |
| . .  . | . . . | .  .   . |
+--------+-------+----------+


Code:
naked triple & xy-wing x <> 5, @ <> 567
+---------+-------+--------+
| @ 56 57 | @ @ @ | @ 67 @ |
| x x  x  | . . . | . .  . |
| x x  x  | . . . | . .  . |
+---------+-------+--------+


Code:
xy-wing  x <> 5
+--------+-------+---------+
| . 56 . | . . . | x  67 x |
| x x  x | . . . | 57 .  . |
| . .  . | . . . | .  .  . |
+--------+-------+---------+


Code:
naked triple(box/Row) x <> 567
+-------+-------+------------+
| x x x | x x x | 567 567 56 |
| . . . | . . . | x   x   x  |
| . . . | . . . | x   x   x  |
+-------+-------+------------+


added:
Code:
naked triple( row) x <>7, @ <> 567
+--------+-------+------------+
| 56 @ @ | @ @ @ | 567 567 @  |
| .  . . | . . . | x   x   x  |
| .  . . | . . . | x   x   x  |
+--------+-------+------------+


probably going to create some confusion with both these posts....

Danny answered the question nicely 2 posts above.
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Sara Brown



Joined: 17 Mar 2010
Posts: 1

PostPosted: Wed Mar 17, 2010 12:46 pm    Post subject: Reply with quote

Hello, The game is so interesting and it will be the hard to solve in the XYZ matrics of the cut and cross check it will made, Very knowledgeable to understand and it will develop the creativity of our mind...
Amazing game i ever seen
Thanks a lot
Sara Brown
Datarecoverysoftware Customer Support Center:
http://www.datarecoverysoftware.com/datarecoverysoftware/support.html
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