25,161
edits
Changes
Created page with "'''Home * Engines * Loop''' FILE:Tigerandturtle.jpg|border|right|thumb| [https://en.wikipedia.org/wiki/Tiger_and_Turtle_%E2%80%93_Magic_Mountain Tiger and..."
'''[[Main Page|Home]] * [[Engines]] * Loop'''
[[FILE:Tigerandturtle.jpg|border|right|thumb| [https://en.wikipedia.org/wiki/Tiger_and_Turtle_%E2%80%93_Magic_Mountain Tiger and Turtle] - illuminated looping <ref>[https://en.wikipedia.org/wiki/Tiger_and_Turtle_%E2%80%93_Magic_Mountain Tiger and Turtle – Magic Mountain] is a monument in the [https://de.wikipedia.org/wiki/Angerpark Angerpark] in [https://en.wikipedia.org/wiki/Duisburg Duisburg], Germany. Here you see its illuminated looping at night, [https://commons.wikimedia.org/wiki/File:Tigerandturtle.jpg Image] by Kleunam, November 18, 2011, [https://creativecommons.org/licenses/by-sa/3.0/ CC BY-SA 3.0], [https://commons.wikimedia.org/wiki/Category:Tiger_and_Turtle_%E2%80%93_Magic_Mountain Category:Tiger and Turtle – Magic Mountain], [https://en.wikipedia.org/wiki/Wikimedia_Commons Wikimedia Commons], [[:Category:Industrial Heritage Trail|The Industrial Heritage Trail]]</ref> ]]
'''Loop''',<br/>
an [[UCI]] compliant chess engine by [[Fritz Reul]] with different [[Board Representation|board representations]] for 32-bit and 64-bit platforms, at times commercial. Loop became subject of its author's Ph.D. thesis ''New Architectures in Computer Chess'' <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess''. Ph.D. Thesis</ref> . Despite different board representation, both Loop versions presumably share same [[Search|search]] and [[Evaluation|evaluation]] with similar features and weights.
=<span id="32bit"></span>32-bit Loop=
The 32-bit program, based on Reul's former program [[List (Program)|List]], relies on a [[Vector Attacks#15x12|15x12 board]] representation in conjunction with disjoint [[Piece-Lists#NewArchitecture|piece-lists]] with adequate [[Move Generation|move generation]] of [[Vector Attacks#NewArchitecture|blocker loops]]. It participated as ''Loop Leiden'' at the [[DOCCC 2006]], becoming strong runner up behind [[Rybka]]. A specially adapted version called ''Loop Express'' became the engine of [[Wii Chess]] for the [https://en.wikipedia.org/wiki/Nintendo Nintendo] [https://en.wikipedia.org/wiki/Wii Wii] [https://en.wikipedia.org/wiki/Video_game_console console] in 2008 <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 2.2.2 Nintendo Wii Chess, pp. 11</ref> . The non-bitboard data-structure of Loop was also applied in [[Chrilly Donninger|Chrilly Donninger's]] chess machine [[Hydra]] <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 2.2.1 The Chess Machine Hydra, pp. 11</ref> .
Reul in his thesis <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 5.1.1 Non-Bitboard Architectures, pp. 96</ref> :
This computerchess architecture was first implemented in the quite successful computerchess engine Loop Leiden 2006. The computerchess architecture was later implemented partially in Hydra and completely in Wii Chess by Nintendo (see Section 2.1). The high performance was just as important for these projects as the simplicity and ease of implementation in the following two environments: (1) the environment of a sophisticated computer-chess machine (Hydra) and (2) the environment of a commercial games console with the highest quality and security standards.
=64-bit Loop=
The [[Bitboards|bitboard]] based Loop applies [[Magic Bitboards]] for [[Sliding Piece Attacks|sliding piece attack generation]]. Further, iterative [[Alpha-Beta|alpha-beta]] bounded [[Static Exchange Evaluation|static exchange evaluation]] was applied to ''Loop Amsterdam'' <ref>[[Fritz Reul]] ('''2010'''). ''Static Exchange Evaluation with αβ-Approach''. [[ICGA Journal#33_1|ICGA Journal, Vol. 33, No. 1]]</ref> , also performing a [[Parallel Search|parallel search]] for a quad-core processor, which played a strong [[WCCC 2007]] in [https://en.wikipedia.org/wiki/Amsterdam Amsterdam], and became Third, behind the later disqualified [[Rybka]], and [[Zappa]] <ref>[https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=173 15th World Computer Chess Championship - Amsterdam 2007 (ICGA Tournaments)]</ref> .
Fritz Reul on an essential reason of Loop's success in Amsterdam in his thesis <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 5.1.2 Magic Hash Functions for Bitboards, pp. 97</ref> :
A complete computer-chess architecture based on hash functions and magic multiplications for the examination of bitboards is implemented in the computerchess engine Loop Amsterdam. This engine was able to reach the 3rd place at the 15th World Computer-Chess Championship, Amsterdam (NL) 2007. An essential reason for the success of this 64-bit computer-chess engine was the use of highly sophisticated perfect hash functions and magic multipliers for the computation of compound bit-patterns (bitboards) via perfect hashing.
=Evaluation=
==Preliminary Considerations==
Evaluation was only marginally covered in Reul's thesis. In ''Preliminary Considerations'' he mentioned discussions with [[Chrilly Donninger]], [[Fabien Letouzey]] and [[Tord Romstad]], and the exchange of source codes <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 1.2 Preliminary Considerations, pp. 3-4</ref> :
This thesis also does not aim at the explicit consideration of known computer-chess architectures, such as [[Rotated Bitboards]] <ref>[[Stuart Cracraft]] ('''1984'''). ''Bitmap move generation in Chess''. [[ICGA Journal#7_3|ICCA Journal, Vol. 7, No. 3]]</ref> <ref>[[Robert Hyatt]] ('''1999'''). ''[http://www.cis.uab.edu/hyatt/bitmaps.html Rotated Bitmaps, a New Twist on an Old Idea]''. [[ICGA Journal#22_4|ICCA Journal, Vol. 22, No. 4]]</ref> or the [[0x88]] representation <ref>[http://web.archive.org/web/20070716111804/www.brucemo.com/compchess/programming/0x88.htm 0x88 Move Generation] by [[Bruce Moreland]]</ref>. Many a reference used in this thesis is not available in a scientifically elaborate form. This includes personal conversations with programmers <ref>[[Chrilly Donninger]] ('''2006'''). ''Discussion with Dr. Christian Donninger''.</ref>, <ref>[[Fabien Letouzey]] ('''2006'''). ''Personal discussion with Fabien Letouzey''.</ref> <ref>[[Tord Romstad]] ('''2007'''). ''Discussion with Tord Romstad''.</ref> and the '''exchange of source codes''' as well as discussions via email. In this way the contents of this thesis can be regarded to be on a state-of the-art level of the research and development in the field of the computer-chess architectures.
==Fruit Evaluation Overlap==
During the [[ICGA Investigations]] concerning the [[Rybka Controversy]] and [[Evaluation Overlap|evaluation overlaps]], 64-bit Loop was inspected by [[Mark Watkins]] who found congruence with the evaluation of [[Fruit|Fruit 2.1]] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1353 Loop 2007 / Fruit 2.1] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], April 18, 2011</ref> . As confirmed by [[David Levy]] <ref> [http://www.chessbase.com/newsdetail.asp?newsid=7926 ICGA/Rybka controversy: Feedback - Allegations against another Chess Engine – The LOOP Program] by [[David Levy]], [[ChessBase|ChessBase News]], February 17, 2012</ref>, the [[ICGA]] has received a complaint on Loop by Fruit author [[Fabien Letouzey]] and an investigation has been started about this case, as already mentioned by Watkins in August 2011 <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1353#p13794 Re: Loop 2007 / Fruit 2.1] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 22, 2011</ref> .
<span id="Complaints"></span>
=Complaints=
[[ICGA]] President [[David Levy]], May 09, 2014 <ref>[https://icga.leidenuniv.nl/?p=919 Complaints against the Chess programs LOOP and THINKER] by [[David Levy]], [[ICGA]] President, May 9, 2014</ref>
The ICGA has received formal complaints against the Chess programs LOOP and [[Thinker|THINKER]], both of which have participated in the World Computer Chess Championship. LOOP was entered by Fritz Reul into the [[WCCC 2007|2007 WCCC]] in Amsterdam. THINKER was entered into the [[WCCC 2010|2010 WCCC]] in Kanazawa.
...
Here we present extracts from the first section of each of [[Mark Watkins]] reports.
'''Loop''' “The version examined here is Loop 2007 (64-bit), which was released at approximately the same time as the WCCC. There is notable similarity to Fruit in the evaluation function (other components were not examined).”
...
Based on the above mentioned reports by Mark Watkins the ICGA is convinced that, at the very least, both Fritz Reul and [[Kerwin Medina]] have a case to answer. Depending on how Reul and/or Medina respond to these allegations the ICGA might decide to conduct further investigations and/or take some form of strong sanctioning action against the programmers. However, the ICGA does not intend to proceed further along the route to strong sanctions for the time being, in order to give these programmers more time in which to make contact with the ICGA President and present their defence to the allegations. If either or both of these programmers fail to do so by December 31st 2014, or refuses to do so, the ICGA will disqualify them from all their results in ICGA events. In the meantime the ICGA has decided to suspend both Fritz Reul and Kerwin Medina from participation in all ICGA events until such time as they have made contact and offered a defence.
=See also=
* [[Coiled]]
* [[Iteration]]
* [[Iterative Search]]
* [[List (Program)|List]]
* [[Wii Chess]]
=Publications=
* [[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess''. Ph.D. Thesis
* [[Fritz Reul]] ('''2010'''). ''Static Exchange Evaluation with αβ-Approach''. [[ICGA Journal#33_1|ICGA Journal, Vol. 33, No. 1]]
=Forum Posts=
==2005 ...==
* [https://www.stmintz.com/ccc/index.php?id=455003 Loop List available soon] by [[Fritz Reul]], [[CCC]], October 11, 2005
: [https://www.stmintz.com/ccc/index.php?id=455043 Re: Loop List commercially available soon] by [[Günther Simon]], [[CCC]], October 11, 2005
* [http://www.talkchess.com/forum/viewtopic.php?t=13270 Loop 13.6 soon available] by [[Gerhard Sonnabend]], [[CCC]], April 20, 2007
* [http://www.talkchess.com/forum/viewtopic.php?t=13764 doing undoing] by [[Fritz Reul]], [[CCC]], May 14, 2007
* [http://www.talkchess.com/forum/viewtopic.php?t=14832 Iterative DTS] by [[Fritz Reul]], [[CCC]], July 02, 2007
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=213390&t=23375 Re: Bob Hyatt says that...] by [[Michael Scheidl|Mike Scheidl]], [[CCC]], August 29, 2008
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=213593&t=23375 Re: Bob Hyatt says that...] by [[Uri Blass]], [[CCC]], August 30, 2008
==2010 ...==
* [http://www.open-chess.org/viewtopic.php?f=5&t=1353 Loop 2007 / Fruit 2.1] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], April 18, 2011 » [[Fruit]]
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27681 Loop as a Fruit clone] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], September 20, 2013
* [http://hiarcs.net/forums/viewtopic.php?t=6707 Complaints against the Chess programs LOOP and THINKER] by [[Harvey Williamson]], [[Computer Chess Forums|Hiarcs Forum]], May 12, 2014
* [http://www.talkchess.com/forum/viewtopic.php?t=52325 Complaints against the Chess programs LOOP and THINKER] by [[Harvey Williamson]], [[CCC]], May 14, 2014
==2015 ...==
* [http://www.open-chess.org/viewtopic.php?f=3&t=2808&start=81 Re: FIDE Rules on ICGA - Rybka controversy] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], May 08, 2015
=External Links=
==Chess Engine==
* [https://www.game-ai-forum.org/icga-tournaments/program.php?id=123 List's ICGA Tournaments] (covers Loop)
* [http://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Loop-List&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 Loop] at [[CCRL|CCRL 40/40]]
* [https://en.wikipedia.org/wiki/Wii_Chess Wii Chess from Wikipedia]
* [https://en.chessbase.com/post/icga-rybka-controversy-feedback ICGA/Rybka controversy: Feedback - Allegations against another Chess Engine – The LOOP Program] by [[David Levy]], [[ChessBase|ChessBase News]], February 17, 2012
* [https://icga.leidenuniv.nl/?p=354 Allegations against two more Chess Engines – The LOOP Program] by [[David Levy]], [[ICGA]] president, May 22, 2012 » [[Thinker]]
* [https://icga.leidenuniv.nl/?p=919 Complaints against the Chess programs LOOP and THINKER] by [[David Levy]], [[ICGA]] President, May 9, 2014
==Misc==
* [https://en.wikipedia.org/wiki/Loop Loop disambiguation page from Wikipedia]
* [https://en.wikipedia.org/wiki/The_Loop The Loop disambiguation page from Wikipedia]
* [https://en.wikipedia.org/wiki/Looping Looping disambiguation page from Wikipedia]
* [https://en.wikipedia.org/wiki/Control_flow#Loops Loop control flow from Wikipedia]
: [https://en.wikipedia.org/wiki/For_loop For loop]
: [https://en.wikipedia.org/wiki/Foreach_loop Foreach loop]
: [https://en.wikipedia.org/wiki/While_loop While loop]
: [https://en.wikipedia.org/wiki/Do_while_loop Do while loop]
: [https://en.wikipedia.org/wiki/Infinite_loop Infinite loop]
=References=
<references />
'''[[Engines|Up one level]]'''
[[Category:UCI]]
[[Category:Commercial]]
[[Category:Industrial Heritage Trail]]
[[FILE:Tigerandturtle.jpg|border|right|thumb| [https://en.wikipedia.org/wiki/Tiger_and_Turtle_%E2%80%93_Magic_Mountain Tiger and Turtle] - illuminated looping <ref>[https://en.wikipedia.org/wiki/Tiger_and_Turtle_%E2%80%93_Magic_Mountain Tiger and Turtle – Magic Mountain] is a monument in the [https://de.wikipedia.org/wiki/Angerpark Angerpark] in [https://en.wikipedia.org/wiki/Duisburg Duisburg], Germany. Here you see its illuminated looping at night, [https://commons.wikimedia.org/wiki/File:Tigerandturtle.jpg Image] by Kleunam, November 18, 2011, [https://creativecommons.org/licenses/by-sa/3.0/ CC BY-SA 3.0], [https://commons.wikimedia.org/wiki/Category:Tiger_and_Turtle_%E2%80%93_Magic_Mountain Category:Tiger and Turtle – Magic Mountain], [https://en.wikipedia.org/wiki/Wikimedia_Commons Wikimedia Commons], [[:Category:Industrial Heritage Trail|The Industrial Heritage Trail]]</ref> ]]
'''Loop''',<br/>
an [[UCI]] compliant chess engine by [[Fritz Reul]] with different [[Board Representation|board representations]] for 32-bit and 64-bit platforms, at times commercial. Loop became subject of its author's Ph.D. thesis ''New Architectures in Computer Chess'' <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess''. Ph.D. Thesis</ref> . Despite different board representation, both Loop versions presumably share same [[Search|search]] and [[Evaluation|evaluation]] with similar features and weights.
=<span id="32bit"></span>32-bit Loop=
The 32-bit program, based on Reul's former program [[List (Program)|List]], relies on a [[Vector Attacks#15x12|15x12 board]] representation in conjunction with disjoint [[Piece-Lists#NewArchitecture|piece-lists]] with adequate [[Move Generation|move generation]] of [[Vector Attacks#NewArchitecture|blocker loops]]. It participated as ''Loop Leiden'' at the [[DOCCC 2006]], becoming strong runner up behind [[Rybka]]. A specially adapted version called ''Loop Express'' became the engine of [[Wii Chess]] for the [https://en.wikipedia.org/wiki/Nintendo Nintendo] [https://en.wikipedia.org/wiki/Wii Wii] [https://en.wikipedia.org/wiki/Video_game_console console] in 2008 <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 2.2.2 Nintendo Wii Chess, pp. 11</ref> . The non-bitboard data-structure of Loop was also applied in [[Chrilly Donninger|Chrilly Donninger's]] chess machine [[Hydra]] <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 2.2.1 The Chess Machine Hydra, pp. 11</ref> .
Reul in his thesis <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 5.1.1 Non-Bitboard Architectures, pp. 96</ref> :
This computerchess architecture was first implemented in the quite successful computerchess engine Loop Leiden 2006. The computerchess architecture was later implemented partially in Hydra and completely in Wii Chess by Nintendo (see Section 2.1). The high performance was just as important for these projects as the simplicity and ease of implementation in the following two environments: (1) the environment of a sophisticated computer-chess machine (Hydra) and (2) the environment of a commercial games console with the highest quality and security standards.
=64-bit Loop=
The [[Bitboards|bitboard]] based Loop applies [[Magic Bitboards]] for [[Sliding Piece Attacks|sliding piece attack generation]]. Further, iterative [[Alpha-Beta|alpha-beta]] bounded [[Static Exchange Evaluation|static exchange evaluation]] was applied to ''Loop Amsterdam'' <ref>[[Fritz Reul]] ('''2010'''). ''Static Exchange Evaluation with αβ-Approach''. [[ICGA Journal#33_1|ICGA Journal, Vol. 33, No. 1]]</ref> , also performing a [[Parallel Search|parallel search]] for a quad-core processor, which played a strong [[WCCC 2007]] in [https://en.wikipedia.org/wiki/Amsterdam Amsterdam], and became Third, behind the later disqualified [[Rybka]], and [[Zappa]] <ref>[https://www.game-ai-forum.org/icga-tournaments/tournament.php?id=173 15th World Computer Chess Championship - Amsterdam 2007 (ICGA Tournaments)]</ref> .
Fritz Reul on an essential reason of Loop's success in Amsterdam in his thesis <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 5.1.2 Magic Hash Functions for Bitboards, pp. 97</ref> :
A complete computer-chess architecture based on hash functions and magic multiplications for the examination of bitboards is implemented in the computerchess engine Loop Amsterdam. This engine was able to reach the 3rd place at the 15th World Computer-Chess Championship, Amsterdam (NL) 2007. An essential reason for the success of this 64-bit computer-chess engine was the use of highly sophisticated perfect hash functions and magic multipliers for the computation of compound bit-patterns (bitboards) via perfect hashing.
=Evaluation=
==Preliminary Considerations==
Evaluation was only marginally covered in Reul's thesis. In ''Preliminary Considerations'' he mentioned discussions with [[Chrilly Donninger]], [[Fabien Letouzey]] and [[Tord Romstad]], and the exchange of source codes <ref>[[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess'', Ph.D. Thesis, 1.2 Preliminary Considerations, pp. 3-4</ref> :
This thesis also does not aim at the explicit consideration of known computer-chess architectures, such as [[Rotated Bitboards]] <ref>[[Stuart Cracraft]] ('''1984'''). ''Bitmap move generation in Chess''. [[ICGA Journal#7_3|ICCA Journal, Vol. 7, No. 3]]</ref> <ref>[[Robert Hyatt]] ('''1999'''). ''[http://www.cis.uab.edu/hyatt/bitmaps.html Rotated Bitmaps, a New Twist on an Old Idea]''. [[ICGA Journal#22_4|ICCA Journal, Vol. 22, No. 4]]</ref> or the [[0x88]] representation <ref>[http://web.archive.org/web/20070716111804/www.brucemo.com/compchess/programming/0x88.htm 0x88 Move Generation] by [[Bruce Moreland]]</ref>. Many a reference used in this thesis is not available in a scientifically elaborate form. This includes personal conversations with programmers <ref>[[Chrilly Donninger]] ('''2006'''). ''Discussion with Dr. Christian Donninger''.</ref>, <ref>[[Fabien Letouzey]] ('''2006'''). ''Personal discussion with Fabien Letouzey''.</ref> <ref>[[Tord Romstad]] ('''2007'''). ''Discussion with Tord Romstad''.</ref> and the '''exchange of source codes''' as well as discussions via email. In this way the contents of this thesis can be regarded to be on a state-of the-art level of the research and development in the field of the computer-chess architectures.
==Fruit Evaluation Overlap==
During the [[ICGA Investigations]] concerning the [[Rybka Controversy]] and [[Evaluation Overlap|evaluation overlaps]], 64-bit Loop was inspected by [[Mark Watkins]] who found congruence with the evaluation of [[Fruit|Fruit 2.1]] <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1353 Loop 2007 / Fruit 2.1] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], April 18, 2011</ref> . As confirmed by [[David Levy]] <ref> [http://www.chessbase.com/newsdetail.asp?newsid=7926 ICGA/Rybka controversy: Feedback - Allegations against another Chess Engine – The LOOP Program] by [[David Levy]], [[ChessBase|ChessBase News]], February 17, 2012</ref>, the [[ICGA]] has received a complaint on Loop by Fruit author [[Fabien Letouzey]] and an investigation has been started about this case, as already mentioned by Watkins in August 2011 <ref>[http://www.open-chess.org/viewtopic.php?f=5&t=1353#p13794 Re: Loop 2007 / Fruit 2.1] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], August 22, 2011</ref> .
<span id="Complaints"></span>
=Complaints=
[[ICGA]] President [[David Levy]], May 09, 2014 <ref>[https://icga.leidenuniv.nl/?p=919 Complaints against the Chess programs LOOP and THINKER] by [[David Levy]], [[ICGA]] President, May 9, 2014</ref>
The ICGA has received formal complaints against the Chess programs LOOP and [[Thinker|THINKER]], both of which have participated in the World Computer Chess Championship. LOOP was entered by Fritz Reul into the [[WCCC 2007|2007 WCCC]] in Amsterdam. THINKER was entered into the [[WCCC 2010|2010 WCCC]] in Kanazawa.
...
Here we present extracts from the first section of each of [[Mark Watkins]] reports.
'''Loop''' “The version examined here is Loop 2007 (64-bit), which was released at approximately the same time as the WCCC. There is notable similarity to Fruit in the evaluation function (other components were not examined).”
...
Based on the above mentioned reports by Mark Watkins the ICGA is convinced that, at the very least, both Fritz Reul and [[Kerwin Medina]] have a case to answer. Depending on how Reul and/or Medina respond to these allegations the ICGA might decide to conduct further investigations and/or take some form of strong sanctioning action against the programmers. However, the ICGA does not intend to proceed further along the route to strong sanctions for the time being, in order to give these programmers more time in which to make contact with the ICGA President and present their defence to the allegations. If either or both of these programmers fail to do so by December 31st 2014, or refuses to do so, the ICGA will disqualify them from all their results in ICGA events. In the meantime the ICGA has decided to suspend both Fritz Reul and Kerwin Medina from participation in all ICGA events until such time as they have made contact and offered a defence.
=See also=
* [[Coiled]]
* [[Iteration]]
* [[Iterative Search]]
* [[List (Program)|List]]
* [[Wii Chess]]
=Publications=
* [[Fritz Reul]] ('''2009'''). ''New Architectures in Computer Chess''. Ph.D. Thesis
* [[Fritz Reul]] ('''2010'''). ''Static Exchange Evaluation with αβ-Approach''. [[ICGA Journal#33_1|ICGA Journal, Vol. 33, No. 1]]
=Forum Posts=
==2005 ...==
* [https://www.stmintz.com/ccc/index.php?id=455003 Loop List available soon] by [[Fritz Reul]], [[CCC]], October 11, 2005
: [https://www.stmintz.com/ccc/index.php?id=455043 Re: Loop List commercially available soon] by [[Günther Simon]], [[CCC]], October 11, 2005
* [http://www.talkchess.com/forum/viewtopic.php?t=13270 Loop 13.6 soon available] by [[Gerhard Sonnabend]], [[CCC]], April 20, 2007
* [http://www.talkchess.com/forum/viewtopic.php?t=13764 doing undoing] by [[Fritz Reul]], [[CCC]], May 14, 2007
* [http://www.talkchess.com/forum/viewtopic.php?t=14832 Iterative DTS] by [[Fritz Reul]], [[CCC]], July 02, 2007
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=213390&t=23375 Re: Bob Hyatt says that...] by [[Michael Scheidl|Mike Scheidl]], [[CCC]], August 29, 2008
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=213593&t=23375 Re: Bob Hyatt says that...] by [[Uri Blass]], [[CCC]], August 30, 2008
==2010 ...==
* [http://www.open-chess.org/viewtopic.php?f=5&t=1353 Loop 2007 / Fruit 2.1] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], April 18, 2011 » [[Fruit]]
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=27681 Loop as a Fruit clone] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], September 20, 2013
* [http://hiarcs.net/forums/viewtopic.php?t=6707 Complaints against the Chess programs LOOP and THINKER] by [[Harvey Williamson]], [[Computer Chess Forums|Hiarcs Forum]], May 12, 2014
* [http://www.talkchess.com/forum/viewtopic.php?t=52325 Complaints against the Chess programs LOOP and THINKER] by [[Harvey Williamson]], [[CCC]], May 14, 2014
==2015 ...==
* [http://www.open-chess.org/viewtopic.php?f=3&t=2808&start=81 Re: FIDE Rules on ICGA - Rybka controversy] by [[Mark Watkins|BB+]], [[Computer Chess Forums|OpenChess Forum]], May 08, 2015
=External Links=
==Chess Engine==
* [https://www.game-ai-forum.org/icga-tournaments/program.php?id=123 List's ICGA Tournaments] (covers Loop)
* [http://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Loop-List&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 Loop] at [[CCRL|CCRL 40/40]]
* [https://en.wikipedia.org/wiki/Wii_Chess Wii Chess from Wikipedia]
* [https://en.chessbase.com/post/icga-rybka-controversy-feedback ICGA/Rybka controversy: Feedback - Allegations against another Chess Engine – The LOOP Program] by [[David Levy]], [[ChessBase|ChessBase News]], February 17, 2012
* [https://icga.leidenuniv.nl/?p=354 Allegations against two more Chess Engines – The LOOP Program] by [[David Levy]], [[ICGA]] president, May 22, 2012 » [[Thinker]]
* [https://icga.leidenuniv.nl/?p=919 Complaints against the Chess programs LOOP and THINKER] by [[David Levy]], [[ICGA]] President, May 9, 2014
==Misc==
* [https://en.wikipedia.org/wiki/Loop Loop disambiguation page from Wikipedia]
* [https://en.wikipedia.org/wiki/The_Loop The Loop disambiguation page from Wikipedia]
* [https://en.wikipedia.org/wiki/Looping Looping disambiguation page from Wikipedia]
* [https://en.wikipedia.org/wiki/Control_flow#Loops Loop control flow from Wikipedia]
: [https://en.wikipedia.org/wiki/For_loop For loop]
: [https://en.wikipedia.org/wiki/Foreach_loop Foreach loop]
: [https://en.wikipedia.org/wiki/While_loop While loop]
: [https://en.wikipedia.org/wiki/Do_while_loop Do while loop]
: [https://en.wikipedia.org/wiki/Infinite_loop Infinite loop]
=References=
<references />
'''[[Engines|Up one level]]'''
[[Category:UCI]]
[[Category:Commercial]]
[[Category:Industrial Heritage Trail]]
