Andscacs

**[[Home]] * [[Engines]] * Andscacs**
|| [[image:andscacs.jpg link="http://www.andscacs.com/"]] ||~ || **Andscacs**,
an [[UCI]] compliant chess engine by [[Daniel José Queraltó]]. Its development started in September 2013, and the first release was published in February 2014 <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=51182|New engine - Andscacs]] by [[Daniel José Queraltó]], [[CCC]], February 06, 2014</ref>. Andscacs soon evolved to a top engine, becoming runner-up at the [[IGWT III]] losing the final from [[Chiron]] with the narrowest margin of 4½ - 5½, but taking revenge one year later at the [[IGWT IV]], this time with 6½ - 5½ to its favour. At the [[WCRCC 2016|Tenth Annual ACCA World Computer Rapid Chess Championship 2016]],  Andscacs emphasized its ambitions, and  became runner-up without losing a single game, but 12 wins and 3 draws, and thus the only program preventing later winner [[Komodo]] from a 100% score.
||
|| Andscacs Logo <ref>Andscacs Logo with [[http://en.wikipedia.org/wiki/Flag_of_Andorra|Flag of Andorra]], [[http://www.andscacs.com/|Andscacs Homepage]]</ref> ||~ ||^ ||
[[toc]]
=Description=
Being a [[Bitboards|bitboard]] engine, Andscacs determines [[Sliding Piece Attacks|sliding piece attacks]] ray-wise, quite similar to the [[Classical Approach|classical approach]] <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=51475&start=11|Re: Andscacs - New version]] by [[Daniel José Queraltó]], [[CCC]], March 03, 2014</ref>. Since version **0.70**,  Andscacs uses [[Magic Bitboards|magic bitboards]] to speed the attack calculations <ref> [[http://www.talkchess.com/forum/viewtopic.php?t=54257|Andscacs - New version 0.70]] by [[Daniel José Queraltó]], [[CCC]], November 05, 2014</ref>.

==Search==
Andscacs applies a [[Principal Variation Search|principal variation search]] with [[Transposition Table|tranposition table]] inside an [[Iterative Deepening|iterative deepening]] framework with [[Aspiration Windows|aspiration windows]] <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=51182|New engine - Andscacs]] by [[Daniel José Queraltó]], [[CCC]], February 06, 2014</ref>. Beside [[Quiescence Search|quiescence]], [[Selectivity|selectivity]] is due to [[Null Move Pruning#AdaptiveNullMovePruning|adaptive null move pruning]], [[Late Move Reductions|late move reductions]], [[Check Extensions|check extensions]], [[Singular Extensions|singular extensions]], [[Razoring|razoring]] and [[Futility Pruning|futility pruning]]. [[Move Ordering|Move ordering]] is further improved by the [[Killer Heuristic|killer heuristic]], [[Internal Iterative Deepening|IID]] and [[Static Exchange Evaluation|static exchange evaluation]], the latter also used to [[Pruning|prune]] bad [[Captures|captures]] in quiescence and futile moves near the horizon. Since version **0.70**, a [[Hash Move|hash move]] is tried in [[Quiescence Search|quiescence search]] even if it’s a [[Quiet Moves|quiet move]]. Trying only [[Captures|captures]] and [[Promotions|promotions]] was clearly weaker <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=54290|Changes in Andscacs 0.70]] by [[Daniel José Queraltó]], [[CCC]], November 08, 2014</ref>. Version 0.80 in Apil 2015 introduced a [[Thread|threaded]] [[Parallel Search|parallel search]] <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=56030|Andscacs - New version 0.80]] by [[Daniel José Queraltó]], [[CCC]], April 17, 2015</ref>, a [[Lazy SMP]] approach <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=55970|Trying to improve lazy smp]] by [[Daniel José Queraltó]], [[CCC]], April 11, 2015</ref>.

==Evaluation==
The [[Evaluation|evaluation]] considers [[Material Tables|material imbalances]], and has [[Piece-Square Tables|piece-square tables]] for [[Middlegame|middlegame]] and [[Endgame|endgame]], [[Point Value|piece values]] adapted by type of positions (open, closed), different types of [[Mobility|piece mobility]], [[King Safety|king safety]] and sophisticated [[Pawn Structure|pawn structure]] evaluation with focus on [[Passed Pawn|passed pawns]], most features smoothed out between [[Game Phases|game phases]] by a [[Tapered Eval|tapered eval]]. Since version 0.62u, evaluation scores are cached with a small [[Evaluation Hash Table|evaluation hash table]] <ref>[[http://www.andscacs.com/|Andscacs Homepage]]</ref>. 

==Tuning==
The about 200 evaluation features were [[Automated Tuning|tuned]] with 750.000 positions to minimize the [[http://en.wikipedia.org/wiki/Standard_deviation|standard deviation]] of [[Stockfish|Stockfish's]] and Andscacs' static evaluation, which initially added a nice Elo boost to Andscacs <ref>[[http://www.talkchess.com/forum/viewtopic.php?t=51182&start=2|Re: New engine - Andscacs]]  by [[Daniel José Queraltó]], [[CCC]], February 06, 2014</ref>, without playing too similar.

=Forum Posts=
==2014==
* [[http://www.talkchess.com/forum/viewtopic.php?t=51182|New engine - Andscacs]] by [[Daniel José Queraltó]], [[CCC]], February 06, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=51218|Andscacs - New version]] by [[Daniel José Queraltó]], [[CCC]], February 09, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=51475|Andscacs - New version]] by [[Daniel José Queraltó]], [[CCC]], March 03, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=51937|Andscacs - New version 0.62w]] by [[Daniel José Queraltó]], [[CCC]], April 10, 2014 
* [[http://www.talkchess.com/forum/viewtopic.php?t=52233|Andscacs - New version 0.62x]] by [[Daniel José Queraltó]], [[CCC]], May 05, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=52572|Andscacs - New version 0.64]] by [[Daniel José Queraltó]], [[CCC]], June 07, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=54257|Andscacs - New version 0.70]] by [[Daniel José Queraltó]], [[CCC]], November 05, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=54290|Changes in Andscacs 0.70]] by [[Daniel José Queraltó]], [[CCC]], November 08, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=54679|Andscacs - New version 0.71]] by [[Daniel José Queraltó]], [[CCC]], December 17, 2014
* [[http://www.talkchess.com/forum/viewtopic.php?t=54700|Changes in Andscacs 0.71]] by [[Daniel José Queraltó]], [[CCC]], December 19, 2014
==2015==
* [[http://www.talkchess.com/forum/viewtopic.php?t=55177|Andscacs - New version 0.72]] by [[Daniel José Queraltó]], [[CCC]], February 01, 2015
* [[http://www.talkchess.com/forum/viewtopic.php?t=55950|Andscacs - Test version 74024]] by [[Daniel José Queraltó]], [[CCC]], April 09, 2015
* [[http://www.talkchess.com/forum/viewtopic.php?t=55970|Trying to improve lazy smp]] by [[Daniel José Queraltó]], [[CCC]], April 11, 2015 » [[Lazy SMP]]
* [[http://www.talkchess.com/forum/viewtopic.php?t=56019|Empirical results with Lazy SMP, YBWC, DTS]] by [[Kai Laskos]], [[CCC]], April 16, 2015 » [[Lazy SMP]], [[Young Brothers Wait Concept|YBWC]], [[Dynamic Tree Splitting|DTS]]
* [[http://www.talkchess.com/forum/viewtopic.php?t=56030|Andscacs - New version 0.80]] by [[Daniel José Queraltó]], [[CCC]], April 17, 2015
* [[http://www.talkchess.com/forum/viewtopic.php?t=56724|Andscacs - New version 0.81]] by [[Daniel José Queraltó]], [[CCC]], June 20, 2015
> [[http://www.talkchess.com/forum/viewtopic.php?t=56724&start=3|Andscacs - New version 0.81 - Detailed changes]] by [[Daniel José Queraltó]], [[CCC]], June 20, 2015
* [[http://www.talkchess.com/forum/viewtopic.php?t=57281|Andscacs - New version 0.82]] by [[Daniel José Queraltó]], [[CCC]],  August 16, 2015
* [[http://www.talkchess.com/forum/viewtopic.php?t=58220|Andscacs - New version 0.83]]  by [[Daniel José Queraltó]], [[CCC]], November 10, 2015 
* [[http://www.talkchess.com/forum/viewtopic.php?t=58512|Andscacs - New version 0.84]] by [[Daniel José Queraltó]], [[CCC]], December 07, 2015
* [[http://www.talkchess.com/forum/viewtopic.php?t=58298&start=52|Re: Why computing K that minimizes the sigmoid func. value?]] by [[Daniel José Queraltó]], [[CCC]], December 07, 2015 » [[Texel's Tuning Method]]
==2016==
* [[http://www.talkchess.com/forum/viewtopic.php?t=59011|Andscacs - New version 0.85]] by [[Daniel José Queraltó]], [[CCC]], January 22, 2016
* [[http://www.talkchess.com/forum/viewtopic.php?t=59615|Andscacs - New version 0.86]] by [[Daniel José Queraltó]], [[CCC]], March 24, 2016
* [[http://www.talkchess.com/forum/viewtopic.php?t=60435|Singular extension]] by [[Daniel José Queraltó]], [[CCC]], June 11, 2016 » [[Singular Extensions]]
* [[http://www.talkchess.com/forum/viewtopic.php?t=60500|Andscacs 0.86.196 BMI2 is available ...]] by [[Frank Quisinsky]], June 15, 2016 » [[BMI2]]
* [[http://www.talkchess.com/forum/viewtopic.php?t=60533|Andscacs - New version 0.87]] by [[Daniel José Queraltó]], [[CCC]], June 19, 2016
* [[http://www.talkchess.com/forum/viewtopic.php?t=60913|Andscacs - New version 0.872]] by [[Daniel José Queraltó]], [[CCC]], July 23, 2016
* [[http://www.talkchess.com/forum/viewtopic.php?t=60940|Detailed changes in Andscacs from 0.86 to 0.872]] by [[Daniel José Queraltó]], [[CCC]], July 25, 2016
* [[http://www.talkchess.com/forum/viewtopic.php?t=61795|Andscacs, developing version]] by [[Daniel José Queraltó]], [[CCC]], October 22, 2016
* [[http://www.talkchess.com/forum/viewtopic.php?t=61868|Andscacs - New version 0.88]] by [[Daniel José Queraltó]], [[CCC]], October 28, 2016
==2017==
* [[http://www.talkchess.com/forum/viewtopic.php?t=63552|Andscacs - New version 0.90]] by [[Daniel José Queraltó]], [[CCC]], March 25, 2017
* [[http://www.talkchess.com/forum/viewtopic.php?t=63944|Andscacs - New version 0.91]] by [[Daniel José Queraltó]], [[CCC]], May 09, 2017
* [[http://www.talkchess.com/forum/viewtopic.php?t=64557|Andscacs new PH feature: first impressions]] by [[Rodolfo Leoni]], [[CCC]], July 08, 2017 » [[Persistent Hash Table]]
* [[http://www.talkchess.com/forum/viewtopic.php?t=65204|Andscacs - New version 0.92]] by [[Daniel José Queraltó]], [[CCC]], September 17, 2017
* [[http://www.talkchess.com/forum/viewtopic.php?t=65632|Andscacs - New version 0.921 with source]] by [[Daniel José Queraltó]], [[CCC]], November 04, 2017 
> [[http://www.talkchess.com/forum/viewtopic.php?t=65632&start=63|Re: Andscacs - New version 0.921 with source]] by [[Jon Dart]], [[CCC]], November 09, 2017 » [[TCEC Season 10]]
> [[http://www.talkchess.com/forum/viewtopic.php?t=65632&start=80|Re: Andscacs - New version 0.921 with source]] by [[Ronald de Man]], [[CCC]], November 11, 2017
* [[http://www.talkchess.com/forum/viewtopic.php?t=66189|Andscacs, test version]] by [[Daniel José Queraltó]], [[CCC]], December 31, 2017
==2018==
* [[http://www.talkchess.com/forum/viewtopic.php?t=66320|Andscacs - New version 0.93]] by [[Daniel José Queraltó]], [[CCC]], January 14, 2018

=External Links=
==Chess Engine==
* [[http://www.andscacs.com/|Andscacs Homepage]]
* [[http://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Andscacs&print=Rating+list&print=Results+table&print=LOS+table&print=Ponder+hit+table&print=Eval+difference+table&print=Comopp+gamenum+table&print=Overlap+table&print=Score+with+common+opponents|Andscacs]] in [[CCRL|CCRL 40/40]]
==Misc==
* Jorge Retamoza Cuarteto - [[https://tango.info/eng/T0370004800|La Cachila]], [[http://jazzstamps.blogspot.de/2013/08/jazzstamp-jazz-hivern-andorra.html|Andorra Jazz Hivern Fest 2013]], [[http://en.wikipedia.org/wiki/YouTube|YouTube]] Video 
> [[http://en.wikipedia.org/wiki/Claudio_Constantini|Claudio Constantini]], [[http://www.apoloybaco.com/jazz/index.php?option=com_content&view=article&id=2630&Itemid=277|Alejandro Di Costanzo]], [[http://www.argentjazz.com.ar/hernan-hock-lleva-su-nuevo-disco-a-boris/|Hernán Hock]], [[http://www.retamoza.com.ar/inicio.htm|Jorge Retamoza]]
> [[media type="youtube" key="2zLpdvq3eMY"]]

=References= 
<references />
=What links here?= 
[[include page="Andscacs" component="backlinks" limit="20"]]
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