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ABK, (Arena's book format)
the opening book format of Arena. It persists a book tree as array of entries, each entry referring one book move with priority and statistics, an entry index of the next move inside a book line (> 0 if any), and an entry index of a possible sibling move (>= 0 if any). The sizeof of an entry is 28, the initial position indexed by 900 1.
Contents
Entry Structure
The array of entries/structures is written to / read from a binary file under Windows (x86), struct and integers implicitely stored little-endian wise:
struct SBookMoveEntry {
char from; /* a1 0, b1 1, ..., h1 7, ... h8 63 */
char to; /* a1 0, b1 1, ..., h1 7, ... h8 63 */
char promotion; /* 0 none, +-1 rook, +-2 knight, +-3 bishop, +-4 queen */
char priority;
int ngames;
int nwon;
int nlost;
int plycount;
int nextMove;
int nextSibling;
} * pOpeningBook;Sample Tree
root index
▼
┌───────────┐ ┌───────────┐
│nextSibling│ ─────────────── ► ────────────── │nextSibling│ ─────────────── ► ...
├───────────┤ ├───────────┤
│ e2-e4 │ │ d2-d4 │
├───────────┤ ├───────────┤
│ nextMove │ │ nextMove │
└───────────┘ └───────────┘
▼ ▼
┌───────────┐ ┌───────────┐ ┌───────────┐ ┌───────────┐ ┌───────────┐ ┌───────────┐ ┌───────────┐ ┌───────────┐
│nextSibling│►│nextSibling│►│nextSibling│►... │nextSibling│►│nextSibling│►│nextSibling│►│nextSibling│►...►│nextSibling│
├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤
│ e7-e5 │ │ c7-c5 │ │ e6-e6 │ │ d7-d5 │ │ g8-f6 │ │ c7-c6 │ │ e7-e6 │ │ f7-f5 │
├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤
│ nextMove │ │ nextMove │ │ nextMove │ │ nextMove │ │ nextMove │ │ nextMove │ │ nextMove │ │ nextMove │
└───────────┘ └───────────┘ └───────────┘ └───────────┘ └───────────┘ └───────────┘ └───────────┘ └───────────┘
▼ ▼ ▼ ▼ ▼ ▼ ▼ ▼
┌───────────┐ ... ┌───────────┐ ┌───────────┐ ... ... ┌───────────┐ ...
│nextSibling│►... │nextSibling│►... │nextSibling│►... │nextSibling│►...
├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤
│ g1-f3 │ │ d2-d4 │ │ c2-c4 │ │ e2-e4 │
├───────────┤ ├───────────┤ ├───────────┤ ├───────────┤
│ nextMove │ │ nextMove │ │ nextMove │ │ nextMove │
└───────────┘ └───────────┘ └───────────┘ └───────────┘
▼ ▼ ▼ ▼
... ... ... ...See also
Forum Posts
2007 ...
- Which is the best general purpose Arena (abk format) Book by Christopher Conkie, CCC, June 04, 2007
- Opening books format by James Constance, CCC, April 14, 2008
Re: Opening books format by Jury Osipov, CCC, April 15, 2008
Re: Opening books format by Richard Pijl, CCC, April 15, 2008
Re: Opening books format by Dann Corbit, CCC, April 15, 2008
Re: Opening books format by Lance Perkins, CCC, April 17, 2008
2010 ...
- Convert .obk books to .abk books? by David Dahlem, CCC, September 15, 2011
- Scid / Scid vs. PC - ChessBase (.ctg) and Arena (.abk) by Norbert Raimund Leisner, CCC, August 19, 2016 » CTG, SCID, Scid vs. PC
- How to use Arena book? by P. Kumar, CCC, February 01, 2017
2020 ...
- abk to pgn tool by Fauzi, FishCooking, September 14, 2020 » PGN
External Links
- Arena Chess GUI - Opening Books
- Commercial Opening Book Fauzi 4.5.abk by Fauzi Akram Dabat
- Free Opening Book Downloads from HIARCS Chess Software
- Arena opening books from Numpty chess 2
References
Re: Opening books format by Jury Osipov, CCC, April 15, 2008↩︎
Scid / Scid vs. PC - ChessBase (.ctg) and Arena (.abk) by Norbert Raimund Leisner, CCC, August 19, 2016↩︎