Older Version
Newer Version
GerdIsenberg
Jul 23, 2017
**[[Home]] * [[Engines]] * Betsabe**
|| [[image:Willem_Drost_-_Batsheba_met_de_brief_van_koning_David.jpg link="http://en.wikipedia.org/wiki/File:Willem_Drost_-_Batsheba_met_de_brief_van_koning_David.jpg"]] ||~ || **Betsabe II**, (Betsabe, Betsabé II)
a [[Chess Engine Communication Protocol]] compliant [[Open Source Engines|open source chess engine]] under the [[Free Software Foundation#GPL|GPL]] written by [[Juan Benitez]] in [[C]], able to run under [[Windows]], [[Linux]], [[Mac OS]] and [[Android]] platforms. Betsabe II is successor of Betsabe, which already played various [[Spanish Computer Chess Championship|Spanish Computer Chess Championships]] in the 90s, notably the [[SCCC 1993]] where it became first Spanish Champion with a 100% score, and the [[SCCC 1994]] as runner-up behind [[Zeus|Zeus II]]. Betsabe was initially based on [[Dieter Steinwender]] and [[Chrilly Donninger|Chrilly Donninger's]] program [[Minimax (program)|Minimax]] <ref>betsabe-II-109-ja-jm/readme.txt</ref>, but differences in [[Search|search]] and [[Evaluation|evaluation]] are substantial. ||
|| Betsabé <ref>[[http://en.wikipedia.org/wiki/File:Willem_Drost_-_Batsheba_met_de_brief_van_koning_David.jpg|Bathsheba holding King David's letter]] by [[Arts#Drost|Willem Drost]], 1654, [[http://en.wikipedia.org/wiki/The_Louvre|Louvre Museum]], [[http://en.wikipedia.org/wiki/Bathsheba|Bathsheba from Wikipedia]]</ref> ||~ ||^ ||
[[toc]]
=Description=
==Board Representation==
Betsabe II maintains a [[10x12 Board|10x12 board]] as internal [[Board Representation|board representation]] and to [[Move Generation|generate moves]]. Definition of (part of) the [[Initial Position|initial position]] <ref>data.h</ref>:
[[code format="cpp"]]
const int Tablero_Inicio[120] = {
FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA,
FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA,
FUERA, T_B, C_B , A_B , D_B , R_B , A_B , C_B , T_B, FUERA,
FUERA, P_B, P_B , P_B , P_B , P_B , P_B , P_B , P_B, FUERA,
FUERA, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, FUERA,
FUERA, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, FUERA,
FUERA, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, FUERA,
FUERA, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, VACIO, FUERA,
FUERA, P_N , P_N , P_N , P_N , P_N , P_N , P_N , P_N, FUERA,
FUERA, T_N, C_N , A_N , D_N , R_N , A_N , C_N , T_N, FUERA,
FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA,
FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA, FUERA};
[[code]]
==Search==
Betsabe II applies [[Principal Variation Search|PVS]] with [[Transposition Table|transposition table]] inside an [[Iterative Deepening|iterative deepening]] [[Depth#FractionalPlies|fractional ply]] framework in conjunction with [[Mate Distance Pruning|mate distance pruning]], [[Internal Iterative Deepening|IID]], [[Null Move Pruning#AdaptiveNullMovePruning|adaptive null move pruning]], [[Late Move Reductions|LMR]], [[Razoring|razoring]], [[Futility Pruning|futility pruning]], [[Static Exchange Evaluation|SEE pruning]] in [[Quiescence Search|quiescence]], and [[Check Extensions|check-]] and [[Capture Extensions|capture extensions]] with transitions to [[Pawn Endgame|pawn endings]]. [[Move Ordering|Move ordering]] is enhanced by [[History Heuristic|history-]] and [[Killer Heuristic|killer heuristic]] with two ordinary [[Killer Move|killer moves]] and one [[Mate Killers|mate killer]] per [[Ply|ply]].
==Evaluation==
The [[Evaluation|evaluation]] might be [[Lazy Evaluation|lazy]] using [[Material|material]] and [[Piece-Square Tables|piece-square tables]] with respect to [[Bound|bounds]], and otherwise considers [[Mobility|mobility]], [[Pawn Structure|pawn structure]], [[King Safety|king safety]] and various [[Evaluation of Pieces|piece terms]].
=Selected Games=
[[SCCC 1999]], round 7, [[Betsabe]] - [[Genesis AR|Genesis]] <ref>[[http://www.stmintz.com/ccc/index.php?id=84977|Spanish Championship: Final Round]] by Sergio Martinez, [[CCC]], December 29, 1999</ref>
[[code]]
[Event "SCCC 1999"]
[Site "Parets del Valles"]
[Date "29.12.99"]
[Round "7"]
[White "Betsabe"]
[Black "Genesis"]
[Result "1-0"]
1.d4 e6 2.e4 d5 3.Nc3 Bb4 4.e5 Bxc3+ 5.bxc3 c5 6.Qg4 g6 7.Nf3 f5 8.Qg5 Qc7
9.Qd2 Nc6 10.Ba3 b6 11.Rb1 Bb7 12.Bd3 Nge7 13.O-O c4 14.Be2 h6 15.Rb2 Qd7
16.Rfb1 g5 17.h3 O-O-O 18.Nh2 Ng6 19.Bd6 Nf4 20.Bf3 Qf7 21.Nf1 Rxd6 22.exd6
Rh7 23.Ng3 Qd7 24.Ne2 Nxe2+ 25.Qxe2 Qxd6 26.a4 Re7 27.Ra1 e5 28.Qd2 e4 29.Bh5
Na5 30.Rba2 f4 31.Re1 Kb8 32.Qc1 Ka8 33.Qb2 e3 34.Raa1 exf2+ 35.Kxf2 Qf6
36.Rxe7 Qxe7 37.Re1 Qd7 38.Re8+ Bc8 39.Rf8 Qe6 40.Bg4 Qe3+ 41.Kf1 Kb7 42.Bxc8+
Kc7 43.Bg4 Nc6 44.Rc8+ Kb7 45.Rxc6 Kxc6 46.Qb5+ Kb7 47.Qxd5+ Kc7 48.Qd7+
1-0
[[code]]
=See also=
* [[David]]
* [[Minimax (program)]]
* [[Various Classifications#Mythology|Mythology]]
* [[Various Classifications#Nobility|Nobility]]
=Forum Posts=
* [[http://www.open-aurec.com/wbforum/viewtopic.php?f=2&t=51551|New engine - Betsabé II 1.0]] by Tony Mokonen, [[Computer Chess Forums|Winboard Forum]], February 18, 2011
* [[http://www.talkchess.com/forum/viewtopic.php?t=53263|Betsabe II 1.47]] by [[Graham Banks]], [[CCC]], August 12, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=64686|Betsabe II 1.75 released]] by [[Graham Banks]], [[CCC]], July 22, 2017
=External Links=
==Chess Engine==
* [[http://kirr.homeunix.org/chess/engines/Jim%20Ablett/BETSABE%20II/|Index of /chess/engines/Jim Ablett/BETSABE II]] hosted by [[Kirill Kryukov]]
* [[http://julien.marcel.free.fr/macchess/Chess_on_Mac/Engines.html|Mac Chess Engines Repository]] hosted by [[Julien Marcel]]
* [[http://www.computerchess.org.uk/ccrl/4040/cgi/engine_details.cgi?print=Details&each_game=1&eng=Betsabe%20II%201.30%2064-bit|Betsabe II 1.30 64-bit]] in [[CCRL|CCRL 40/40]]
==Misc==
* [[http://es.wikipedia.org/wiki/Betsab%C3%A9|Betsabé - Wikipedia.es]] (Spanish)
* [[http://en.wikipedia.org/wiki/Bathsheba|Bathsheba from Wikipedia]]
* [[http://en.wikipedia.org/wiki/Books_of_Samuel|Books of Samuel from Wikipedia]]
* [[http://www.usnews.com/news/religion/articles/2008/01/25/bathsheba-is-one-of-the-most-beguiling-characters-in-the-bible|Bathsheba is One of the Most Beguiling Characters in the Bible]] by [[http://www.usnews.com/topics/author/jessica_feinstein|Jessica Feinstein]], [[http://en.wikipedia.org/wiki/U.S._News_%26_World_Report|US News & World Report]], January 25, 2008
* [[http://en.wikipedia.org/wiki/David_and_Bathsheba_%28film%29|David and Bathsheba (film) from Wikipedia]]
=References=
<references />
=What links here?=
[[include page="Betsabe" component="backlinks" limit="20"]]
**[[Engines|Up one level]]**