Loop Program
[ Tiger and Turtle - illuminated looping [1] Loop,
an UCI compliant chess engine by Fritz Reul with different 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 [2] . Despite different board representation, both Loop versions presumably share same search and evaluation with similar features and weights.
64-bit Loop
The bitboard based Loop applies Magic Bitboards for sliding piece attack generation. Further, iterative alpha-beta bounded static exchange evaluation was applied to Loop Amsterdam [6] , also performing a parallel search for a quad-core processor, which played a strong WCCC 2007 in Amsterdam, and became Third, behind the later disqualified Rybka, and Zappa [7].
Fritz Reul on an essential reason of Loop’s success in Amsterdam in his thesis [8] :
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 [9] :
Fruit Evaluation Overlap
During the ICGA Investigations concerning the Rybka Controversy and evaluation overlaps, 64-bit Loop was inspected by Mark Watkins who found congruence with the evaluation of Fruit 2.1 [16] . As confirmed by David Levy [17], 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 [18] .
Complaints
ICGA President David Levy, May 09, 2014 [19]
See also
Publications
- Fritz Reul (2009). New Architectures in Computer Chess. Ph.D. thesis, pdf
- Fritz Reul (2010). Static Exchange Evaluation with αβ-Approach. ICGA Journal, Vol. 33, No. 1
Forum Posts
2005 …
- Loop List available soon by Fritz Reul, CCC, October 11, 2005
Re: Loop List commercially available soon by Günther Simon, CCC, October 11, 2005
- Loop 13.6 soon available by Gerhard Sonnabend, CCC, April 20, 2007
- doing undoing by Fritz Reul, CCC, May 14, 2007
- Iterative DTS by Fritz Reul, CCC, July 02, 2007
- Re: Bob Hyatt says that… by Mike Scheidl, CCC, August 29, 2008
- Re: Bob Hyatt says that… by Uri Blass, CCC, August 30, 2008
2010 …
- Loop 2007 / Fruit 2.1 by BB+, OpenChess Forum, April 18, 2011 » Fruit
- Loop as a Fruit clone by Rebel, Rybka Forum, September 20, 2013
- Complaints against the Chess programs LOOP and THINKER by Harvey Williamson, Hiarcs Forum, May 12, 2014
- Complaints against the Chess programs LOOP and THINKER by Harvey Williamson, CCC, May 14, 2014
2015 …
- Re: FIDE Rules on ICGA - Rybka controversy by BB+, OpenChess Forum, May 08, 2015
External Links
Chess Engine
- Loop Computer Chess
- List’s ICGA Tournaments (covers Loop)
- Engine Download List from Ron Murawski’s Computer-Chess Wiki
- Loop at CCRL 40/40
- Wii Chess from Wikipedia
- ICGA/Rybka controversy: Feedback - Allegations against another Chess Engine – The LOOP Program by David Levy, ChessBase News, February 17, 2012
- Allegations against two more Chess Engines – The LOOP Program by David Levy, ICGA president, May 22, 2012 » Thinker
- Complaints against the Chess programs LOOP and THINKER by David Levy, ICGA President, May 9, 2014
Misc
- Loop disambiguation page from Wikipedia
- The Loop disambiguation page from Wikipedia
- Looping disambiguation page from Wikipedia
- Loop control flow from Wikipedia
For loop Foreach loop While loop Do while loop Infinite loop
- Dirty Loops - Songs for Lovers - Coffee Break is over, Guitar cover with Sandeep Mohan, YouTube Video
References
- ↑ Tiger and Turtle – Magic Mountain is a monument in the Angerpark in Duisburg, Germany. Here you see its illuminated looping at night, Image by Kleunam, November 18, 2011, CC BY-SA 3.0, Category:Tiger and Turtle – Magic Mountain, Wikimedia Commons, The Industrial Heritage Trail
- ↑ Fritz Reul (2009). New Architectures in Computer Chess. Ph.D. thesis
- ↑ Fritz Reul (2009). New Architectures in Computer Chess, Ph.D. thesis, 2.2.2 Nintendo Wii Chess, pp. 11
- ↑ Fritz Reul (2009). New Architectures in Computer Chess, Ph.D. thesis, 2.2.1 The Chess Machine Hydra, pp. 11
- ↑ Fritz Reul (2009). New Architectures in Computer Chess, Ph.D. thesis, 5.1.1 Non-Bitboard Architectures, pp. 96
- ↑ Fritz Reul (2010). Static Exchange Evaluation with αβ-Approach. ICGA Journal, Vol. 33, No. 1
- ↑ 15th World Computer Chess Championship - Amsterdam 2007 (ICGA Tournaments)
- ↑ Fritz Reul (2009). New Architectures in Computer Chess, Ph.D. thesis, 5.1.2 Magic Hash Functions for Bitboards, pp. 97
- ↑ Fritz Reul (2009). New Architectures in Computer Chess, Ph.D. thesis, 1.2 Preliminary Considerations, pp. 3-4
- ↑ Stuart Cracraft (1984). Bitmap move generation in Chess. ICCA Journal, Vol. 7, No. 3
- ↑ Robert Hyatt (1999). Rotated Bitmaps, a New Twist on an Old Idea. ICCA Journal, Vol. 22, No. 4
- ↑ 0x88 Move Generation by Bruce Moreland
- ↑ Chrilly Donninger (2006). Discussion with Dr. Christian Donninger.
- ↑ Fabien Letouzey (2006). Personal discussion with Fabien Letouzey.
- ↑ Tord Romstad (2007). Discussion with Tord Romstad.
- ↑ Loop 2007 / Fruit 2.1 by BB+, OpenChess Forum, April 18, 2011
- ↑ ICGA/Rybka controversy: Feedback - Allegations against another Chess Engine – The LOOP Program by David Levy, ChessBase News, February 17, 2012
- ↑ Re: Loop 2007 / Fruit 2.1 by BB+, OpenChess Forum, August 22, 2011
- ↑ Complaints against the Chess programs LOOP and THINKER by David Levy, ICGA President, May 9, 2014