Difference between revisions of "Elephant"

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=Description=  
 
=Description=  
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Elephant applies [[Principal Variation Search|PVS]] [[Alpha-Beta|alpha-beta]] with [[Transposition Table|transposition table]], [[Quiescence Search|quiescence]], [[Null Move Pruning#AdaptiveNullMovePruning|adaptive null move pruning]], [[Internal Iterative Deepening|IID]], [[Razoring|razoring]], [[Futility Pruning|futility pruning]] and various [[Extensions|extensions]], embedded inside an [[Depth#FractionalPlies|fractional ply]] [[Iterative Deepening|iterative deepening]] framework. [[Move Ordering|Move ordering]] at the [[Root|root]] is based on [[Node|node count]], and otherwise considers [[Hash Move|hash move]] including [[Principal variation|principle variation]], [[Static Exchange Evaluation|static exchange evaluation]], [[Killer Heuristic|killer-]] and [[History Heuristic|history heuristic]]. [[Evaluation]] might be [[Lazy Evaluation|lazy]] and takes [[Material|material]], [[Pawn Hash Table|cached]] [[Pawn Structure|pawn structure]], [[King Safety|king safety]], [[Piece-Square Tables|piece-squares tables]], [[Mobility|mobility]] and multiple other terms into account. Elephant was used as testbed to compare various [[Bitboards|bitboard]] techniques in generating [[Sliding Piece Attacks|sliding piece attacks]] <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=140111&t=16002 Re: BitBoard Tests Magic v Non-Rotated 32 Bits v 64 Bits] by [[Harald Lüßen]], [[CCC]], August 24, 2007</ref>, in particular [[Exploding Bitboards|Exploding-]] and [[Sherwin Bitboards]].
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Elephant applies [[Principal Variation Search|PVS]] [[Alpha-Beta|alpha-beta]] with [[Transposition Table|transposition table]], [[Quiescence Search|quiescence]], [[Null Move Pruning#AdaptiveNullMovePruning|adaptive null move pruning]], [[Internal Iterative Deepening|IID]], [[Razoring|razoring]], [[Futility Pruning|futility pruning]] and various [[Extensions|extensions]], embedded inside an [[Depth#FractionalPlies|fractional ply]] [[Iterative Deepening|iterative deepening]] framework. [[Move Ordering|Move ordering]] at the [[Root|root]] is based on [[Node|node count]], and otherwise considers [[Hash Move|hash move]] including [[Principal Variation|principle variation]], [[Static Exchange Evaluation|static exchange evaluation]], [[Killer Heuristic|killer-]] and [[History Heuristic|history heuristic]]. [[Evaluation]] might be [[Lazy Evaluation|lazy]] and takes [[Material|material]], [[Pawn Hash Table|cached]] [[Pawn Structure|pawn structure]], [[King Safety|king safety]], [[Piece-Square Tables|piece-squares tables]], [[Mobility|mobility]] and multiple other terms into account. Elephant was used as testbed to compare various [[Bitboards|bitboard]] techniques in generating [[Sliding Piece Attacks|sliding piece attacks]] <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=140111&t=16002 Re: BitBoard Tests Magic v Non-Rotated 32 Bits v 64 Bits] by [[Harald Lüßen]], [[CCC]], August 24, 2007</ref>, in particular [[Exploding Bitboards|Exploding-]] and [[Sherwin Bitboards]].
  
 
=See also=  
 
=See also=  
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=External Links=  
 
=External Links=  
 
==Chess Engine==  
 
==Chess Engine==  
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* [http://wbec-ridderkerk.nl/html/details1/Elephant.html Elephant] from [[WBEC|WBEC Ridderkerk]]
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* [https://web.archive.org/web/20120105073311/http://wbec-ridderkerk.nl/html/details1/Elephant.html Elephant] from [[WBEC|WBEC Ridderkerk]] ([https://en.wikipedia.org/wiki/Wayback_Machine Wayback Machine])
 
* [http://www.computerchess.org.uk/ccrl/404/cgi/engine_details.cgi?print=Details&eng=Elephant%201.06 Elephant 1.06] in [[CCRL|CCRL 40/4]]
 
* [http://www.computerchess.org.uk/ccrl/404/cgi/engine_details.cgi?print=Details&eng=Elephant%201.06 Elephant 1.06] in [[CCRL|CCRL 40/4]]
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==Chess and Variants==  
 
==Chess and Variants==  
 
* [http://history.chess.free.fr/india.htm Indian Chess Sets]
 
* [http://history.chess.free.fr/india.htm Indian Chess Sets]
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* [https://en.wikipedia.org/wiki/Blind_men_and_an_elephant Blind men and an elephant - Wkipedia]
 
* [https://en.wikipedia.org/wiki/Blind_men_and_an_elephant Blind men and an elephant - Wkipedia]
 
* [https://en.wikipedia.org/wiki/War_elephant War elephant from Wikipedia]
 
* [https://en.wikipedia.org/wiki/War_elephant War elephant from Wikipedia]
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* [[:Category:King Crimson|King Crimson]] - [http://www.elephant-talk.com/wiki/ETWiki_Home Elephant Talk], live on [https://en.wikipedia.org/wiki/Fridays_%28TV_series%29 Fridays] (1982), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
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* [[:Category:King Crimson|King Crimson]] - [http://www.elephant-talk.com/wiki/ETWiki_Home Elephant Talk], live on [https://en.wikipedia.org/wiki/Fridays_%28TV_series%29 Fridays] (1981), [https://en.wikipedia.org/wiki/YouTube YouTube] Video
 
: lineup: [https://en.wikipedia.org/wiki/Tony_Levin Tony Levin], [[:Category:Adrian Belew|Adrian Belew]], [[:Category:Bill Bruford|Bill Bruford]], [[:Category:Robert Fripp|Robert Fripp]]
 
: lineup: [https://en.wikipedia.org/wiki/Tony_Levin Tony Levin], [[:Category:Adrian Belew|Adrian Belew]], [[:Category:Bill Bruford|Bill Bruford]], [[:Category:Robert Fripp|Robert Fripp]]
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: {{#evu:https://www.youtube.com/watch?v=GTQrlDzqUCA|alignment=left|valignment=top}}
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: {{#evu:https://www.youtube.com/watch?v=p5Eoek8a500|alignment=left|valignment=top}}
  
 
=References=  
 
=References=  
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'''[[Engines|Up one Level]]'''
 
'''[[Engines|Up one Level]]'''
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[[Category:WinBoard]]
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[[Category:PC]]
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[[Category:X86]]
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[[Category:X64]]
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[[Category:Windows]]
 
[[Category:Industrial Heritage Trail]]
 
[[Category:Industrial Heritage Trail]]
 
[[Category:Mammal]]
 
[[Category:Mammal]]

Revision as of 19:22, 12 September 2020

Home * Engines * Elephant

The Glas Elephant [1] in Hamm [2]

Elephant,
a WinBoard compatible chess engine written by Harald Lüßen in C++, first released in March 2004 [3] . The name was chosen due to the connection with pieces in Chaturanga, Chinese Chess and chess, such as rook and bishop [4] , because elephants are known to be intelligent, and further due its author's weight [5] .

Description

Elephant applies PVS alpha-beta with transposition table, quiescence, adaptive null move pruning, IID, razoring, futility pruning and various extensions, embedded inside an fractional ply iterative deepening framework. Move ordering at the root is based on node count, and otherwise considers hash move including principle variation, static exchange evaluation, killer- and history heuristic. Evaluation might be lazy and takes material, cached pawn structure, king safety, piece-squares tables, mobility and multiple other terms into account. Elephant was used as testbed to compare various bitboard techniques in generating sliding piece attacks [6], in particular Exploding- and Sherwin Bitboards.

See also

Forum Posts

External Links

Chess Engine

Chess and Variants

Misc

lineup: Tony Levin, Adrian Belew, Bill Bruford, Robert Fripp

References

  1. ↑ The Glas Elephant, Maximilianpark, Hamm, North Rhine-Westphalia, Germany, The Industrial Heritage Trail
  2. ↑ Elefantenparade – HammWiki
  3. ↑ Elephant from WBEC Ridderkerk
  4. ↑ Re: Elephant by Eugene Nalimov, CCC, March 26, 2001
  5. ↑ Elephant 1.00, a new winboard engine by Harald Lüßen, CCC, March 15, 2004
  6. ↑ Re: BitBoard Tests Magic v Non-Rotated 32 Bits v 64 Bits by Harald Lüßen, CCC, August 24, 2007

Up one Level

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