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Rambling about Fish -- Take with a Grain of Salt!

 
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daj95376



Joined: 23 Aug 2008
Posts: 3855

PostPosted: Sat Jan 17, 2009 7:30 pm    Post subject: Rambling about Fish -- Take with a Grain of Salt! Reply with quote

There's no way that I can do a complete presentation on FISH. What I will attempt to do is present relevant information and links to where you can learn more. An important thing to remember is that candidate cells exist in a candidate grid from a real puzzle.

----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- -----

There are (at least) two ways to view Fish.

1) As NxN Base Sectors by Cover Sectors with fin cells possible in the Base Sectors of a candidate grid.

2) As Nx(N+k) Base Sectors by Cover Sectors -- with "k" of the Cover Sectors called Fin Sectors. Obi-Wahn documented this approach. RonK's approach is similar/identical.

Most of the following is from ... The Ultimate Fish Guide: link

Although TUFG was started by tarek, RonK was a significant contributor.

I take full responsibility for rewording of definitions below -- especially the incorrect ones!

===== ===== ===== ===== ===== ===== ===== ===== ===== NxN Fish

Sector wrote:
A collective term for row/column/box.

Line wrote:
A collective term for row/column.

Candidate wrote:
One of several possible digits in a sudoku puzzle.

Fish wrote:
Candidate cells mapped onto NxN Base Sectors by Cover Sectors.
The N Base Sectors are called the Base Set.
The N Cover Sectors are called the Cover Set.
A sector can not appear in both the Base Set and the Cover Set.
The candidate cells are divided into vertices, fin cells, and elimination cells.
The type of sectors forming the Base and Cover Sectors determines fish Shape or configuration.
The number of sectors forming the Base and Cover Sectors is usually termed the fish Size.
The type and number of sectors forming the fish determines the fish.

Vertex wrote:
A candidate cell at the intersection of just one Base Sector and one Cover Sector.

Fin Cell wrote:
A candidate cell that exist in more Base Sectors than Cover Sectors. A fish with one or more fin cells is a finned fish.

Fin -- Myth Jellies & Asellus wrote:
The set of all fin cells. Only one fin possible.

Fin -- RonK wrote:
A Fin Sector that would be used in (2). One or two fins possible.

Elimination Cell wrote:
A candidate cell that exists in more Cover sectors than Base sectors and is a peer to all fin cells.

Naming of Fish:

Code:
The fish Name consists of 2 sections: Shape and Size

Shape of Fish:

Code:
1.  basic         : N x N line. (no fin)
2a. Finned        : N x N lines (with fin, the pattern is limited to "basic fish with extra candidates")
2b. Sashimi       : N x N lines (with fin, not limited to 2a)
3.  Franken       : N (rows+boxes) x N (columns+boxes) (no fins)   -or- vv for rows/columns
4.  Finned Franken: N (rows+boxes) x N (columns+boxes) (with fins) -or- vv for rows/columns
5.  Mutant        : N x N sectors (no fins)
6.  Finned Mutant : N x N sectors (with fins)
7.  Kraken        : Any fish (1-6) that requires life support (information from outside the pattern)
________________________________________________________________________________________________________

Size of Fish:

Code:
1. 1-Fish (aka Cyclopsfish): All elements are in 1 x 1 sector
2. X-Wing                  : All elements are in 2 x 2 sectors
3. Swordfish               : All elements are in 3 x 3 sectors
4. Jellyfish               : All elements are in 4 x 4 sectors
5. Squirmbag (aka Starfish): All elements are in 5 x 5 sectors
6. Whale                   : All elements are in 6 x 6 sectors
7. Leviathan               : All elements are in 7 x 7 sectors

===== ===== ===== ===== ===== ===== ===== ===== ===== Nx(N+k) Fish

I suggest the following threads by Obi-Wahn.

Obi-Wahn #1: Initial presentation with lots of good, basic terminology. link

Obi-Wahn #2: Where he refines this approach. link

daj95376 variant for NxN Fish: link


Last edited by daj95376 on Fri May 01, 2009 9:31 pm; edited 1 time in total
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wapati



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

PostPosted: Sun Jan 18, 2009 6:11 pm    Post subject: Reply with quote

I welcome the thread.

I do see fish and I don't use colors.
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