25,161
edits
Changes
no edit summary
'''[[Main Page|Home]] * [[Engines]] * Koivisto'''
[[FILE:Hjalmar Munsterhjelm - Koivikko ja ruispelto - A II 1169 - Finnish National Gallery.jpg|,|border|right|thumb| [[:Category:Hjalmar Munsterhjelm|Hjalmar Munsterhjelm]] - Koivikko ja ruispelto
<ref>[[:Category:Hjalmar Munsterhjelm|Hjalmar Munsterhjelm]] - Koivikko ja ruispelto (Birch and rye field), 1876, [https://en.wikipedia.org/wiki/Finnish_National_Gallery Finnish National Gallery], [https://en.wikipedia.org/wiki/Wikimedia_Commons Wikimedia Commons]</ref> ]]
'''Koivisto''',<br/>
an [[UCI]] compliant [[:Category:Open Source|open source]] chess engine by [[Kim Kåhre]] and [[Finn Eggers]] et al., at times supported by [[Eugenio Bruno]], written in [[Cpp|C++]],
and first released on [https://en.wikipedia.org/wiki/GitHub GitHub] in September 2020 under the [[Free Software Foundation#GPL|GPL v3.0]].
The [[Bitboards|bitboard]] engine provides [[Automated Tuning|automated evaluation tuning]] by [[Automated Tuning#LogisticRegression|logistic regression]],
either using [https://en.wikipedia.org/wiki/Stochastic_gradient_descent stochastic gradient descent] or [https://en.wikipedia.org/wiki/Stochastic_gradient_descent#AdaGrad AdaGrad].
=Features=
* [[Magic Bitboards]]
==[[Search]]==
* [[Lazy SMP]] (2.0)
* [[Iterative Deepening]]
* [[Aspiration Windows]] (3.0)
* [[Principal Variation Search]]
* [[Transposition Table]]
** [[Quiescence Search]]
==[[Evaluation]]==
* [[NNUE]] (5.0)
* [[Tapered Eval]]
* [[Piece-Square Tables]] of [[Float|floats]]
** [[Isolated Pawn]]
** [[Passed Pawn]]
** [[Blockade of Stop]] (3.0)
** [[Backward Pawns (Bitboards)|Backward Pawns]]
** [[Open Pawns (Bitboards)|Open Pawns]]
** [[King Safety#Attacking|Attacking King Zone]]
** [[King Safety#KingTropism|King Tropism]]
** [[Castling Rights]] (3.0)
* [[Tempo]] (3.0)
* [[Draw Evaluation]] (3.0)
* [[Float]] [[SSE|SSE]] [https://en.wikipedia.org/wiki/Dot_product Dot products] <ref>[https://en.wikipedia.org/wiki/Dot_product Dot products] using [https://software.intel.com/sites/landingpage/IntrinsicsGuide/#text=_mm_mul_ps&expand=3928 _mm_mul_ps], [https://software.intel.com/sites/landingpage/IntrinsicsGuide/#text=_mm_add_ps&expand=3928,133 _mm_add_ps]</ref>
* [[Automated Tuning]] by [[Automated Tuning#LogisticRegression|Logistic Regression]]
=Forum Posts=
==2020==
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=72613&start=353 Re: New engine releases 2020] by [[Finn Eggers]], [[CCC]], September 02, 2020
: [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=72613&start=357 Re: New engine releases 2020] by [[Finn Eggers]], [[CCC]], September 03, 2020
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=75001 Koivisto] by [[Gerd Isenberg]], [[CCC]], September 04, 2020
: [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=75001&start=4 Re: Koivisto] by [[Finn Eggers]], [[CCC]], September 04, 2020
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=75052 Koivisto 2.0] by [[Finn Eggers]], [[CCC]], September 08, 2020
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=75423 Koivisto 3.0 (Including binaries)] by [[Kim Kåhre]], [[CCC]], October 17, 2020
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=75742 Koivisto v4.0 release] by [[Eugenio Bruno]], [[CCC]], November 09, 2020
==2021==
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=77664 Koivisto 5.0] by [[Finn Eggers]], [[CCC]], July 07, 2021
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=77766 Koivisto 6.0] by [[Finn Eggers]], [[CCC]], July 21, 2021
* [https://www.talkchess.com/forum3/viewtopic.php?f=2&t=78560 Koivisto 7.0] by [[Finn Eggers]], [[CCC]], October 31, 2021
==2022==
* [https://www.talkchess.com/forum3/viewtopic.php?f=2&t=79523 Koivisto 8.0] by [[Finn Eggers]], [[CCC]], March 15, 2022
=External Links=
==Chess Engine==
* [https://github.com/Luecx/Koivisto GitHub - Luecx/Koivisto: UCI Chess engine]
** [https://github.com/Luecx/Koivisto/wiki/Evaluation Evaluation · Luecx/Koivisto Wiki · GitHub]
** [https://github.com/Luecx/Koivisto/wiki/Regression-tests Regression tests · Luecx/Koivisto Wiki · GitHub]
* [https://koivisto-chess.com/ Koivisto Chess]
* [https://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Koivisto&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 Koivisto] in [[CCRL|CCRL 40/15]]
==Misc==
* [https://en.wiktionary.org/wiki/Koivisto Koivisto - Wiktionary]
[[Category:GPL]]
[[Category:UCI]]
[[Category:NNUE]]
[[Category:Linux]]
[[Category:Windows]]
[[Category:X64]]
[[Category:PC]]
[[Category:OpenBench]]
[[Category:Plant]]
[[Category:Hjalmar Munsterhjelm]]
