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Created page with "'''Home * Engines * Houdini''' [[FILE:Grim game.jpg|border|right|thumb|240px| [https://en.wikipedia.org/wiki/Harry_Houdini Houdini] in "[https://en.wikipedi..."
'''[[Main Page|Home]] * [[Engines]] * Houdini'''
[[FILE:Grim game.jpg|border|right|thumb|240px| [https://en.wikipedia.org/wiki/Harry_Houdini Houdini] in "[https://en.wikipedia.org/wiki/The_Grim_Game The Grim Game]" <ref>[https://en.wikipedia.org/wiki/The_Grim_Game The Grim Game] a 1919 [https://en.wikipedia.org/wiki/Silent_film silent film] starring [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini]</ref> ]]
'''Houdini''',<br/>
a chess engine by [[Robert Houdart]], which appeared in 2010 as closed source engine, free for non-commercial use. In January 2011, Houdini '''1.5''' was leading [[Ingo Bauer|Ingo Bauer's]] [[IPON]] [[Engine Rating Lists|rating list]] <ref>[http://www.inwoba.de/News2009_2011.7z IPON-Rating-List Archive 2009/2010/2011] by [[Ingo Bauer]]</ref> . Houdini '''2''', released in September 2011, is commercial and bundled with a number of [[ChessOK]] products, such as [[Aquarium]], [[Chess Assistant]] <ref>[http://chessok.com/?p=25808 Houdini 2 Aquarium products family has been released!], [[ChessOK]], October 07, 2011</ref>, and since December 2011, [[Chess King]] <ref>[http://chessok.com/?p=26441 Chess King Released], [[ChessOK]], December 14, 2011</ref>. Houdini 1.5a remains available as a free download <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=421920&t=40245 Re: Houdini 2 is released] by [[Robert Houdart]], [[CCC]], September 02, 2011</ref>. Houdini '''3''', released in October 2012, has further improved by more than 50 Elo points <ref>[http://www.inwoba.de/index.html IPON-Rating-List, 2012.10.17] by [[Ingo Bauer]]</ref> . According to its author, Houdini 3 applies a accelerated [[Principal Variation Search|principal variation search]], also dubbed "Smart" [[Fail-High]]. If a different move becomes [[Best Move|best]] at very high [[Depth|search depths]] at the [[Root|root]], re-searches to determine its [[Exact Score|exact score]] and the new [[Principal Variation|principal variation]] are done faster due to a reduced search depth, presumably in conjunction with [[Extensions|extensions]] along the PV <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=488422&t=45624 Re: Houdini 3 reducing the depth feature] by [[Robert Houdart]], [[CCC]], October 19, 2012</ref> . Since November 2012, Houdini 3 is available as [[ChessBase]] engine <ref>[http://chessbase-shop.com/en/products/houdini_3_standard_multiprocessor_version Houdini 3 Standard multiprocessor version], [[ChessBase|ChessBase Shop]]</ref> . Houdini '''4''', released in November 2013, was about 50 Elo stronger than its predecessor, and features 6-men [[Syzygy Bases|Syzygy bases]].
<span id="5"></span>
=Houdini 5=
Released about three years after the previous version, in November 2016, '''Houdini 5''' is vastly improved being about 200 Elo stronger than Houdini 4. It has a completely rewritten [[Evaluation|evaluation]] with more aggressive [[King Safety|king safety]] and sophisticated [[Mobility|piece mobility]], features a more [[Selectivity|selective]] [[Search|search]], exploring critical variations significantly deeper, and for hardware with multiple processors, [[Lazy SMP]]. Houdini '''5 Pro''' supports up to 128 [[Thread|threads]], up to 128 GiB of [[Shared Hash Table|hash memory]], [[Memory#HugePages|large memory pages]], [[NUMA|NUMA-architecture]], and [[Nalimov Tablebases|Nalimov tablebases]] to find the shortest path to [[Checkmate|mate]].
A development version of Houdini 5 qualified for [[TCEC Season 9#Superfinal|TCEC Season 9 Superfinal]], and even won the [[TCEC Season 9#Rapid|TCEC Season 9 Rapid tournament]]. The final release version of Houdini 5 is about 30 Elo stronger than the engine that played in the TCEC tournament so far. But that was apparently not enough for [[Stockfish|Stockfish 8]] in long time control matches - Houdini 5 lost the 100 game [[TCEC Season 9#Superfinal|Superfinal]] with 45½ - 54½.
<span id="6"></span>
=Houdini 6=
Released in September 2017, Houdini '''6''' again improved in [[Search|search]] and [[Evaluation|evaluation]] to add another 50-60 Elo in [[Playing Strength|strength]], which roughly corresponds to doubling the computational power of the computer <ref>[http://www.cruxis.com/chess/houdini.htm Houdini Chess Engine]</ref>. '''Houdini 6.03''' won the [[TCEC Season 10#Superfinal|TCEC Season 10 Superfinal]] versus [[Komodo|Komodo 1970.00]], a successor of Komodo 11, with '''53 - 47''' (+15=76-9) <ref>[http://www.chessdom.com/houdini-is-tcec-season-10-champion/ Houdini is TCEC Season 10 champion!], [[Chessdom]], December 07, 2017</ref> <ref>[http://www.chessdom.com/interview-with-robert-houdart-author-of-the-champion-engine-houdini/ Interview with Robert Houdart, author of the champion engine Houdini], [[Chessdom]], December 08, 2017</ref>.
=Houdini's Origin=
Robert Houdart claims his engine is original <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=534&start=20#p4798 Re: Why Is Houdini Not Entered In The WCCC??] by [[Robert Houdart]], [[Computer Chess Forums|Open Chess Forum]], August 04, 2010</ref>, and admits taking ideas from the open source programs [[Ippolit|Ippolit/Robbolito]], [[Stockfish]] and [[Crafty]] <ref>[http://www.cruxis.com/chess/houdini.htm Houdini Chess Engine - Acknowledgements]</ref> . Other programmers and forum members raised suspicions that Robert took ideas from the controversial Ippolit/Robbolito source code too literally as initial base of his program <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=534&start=40#p5084 Re: Why Is Houdini Not Entered In The WCCC??] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|Open Chess Forum]], August 09, 2010</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=534&start=40#p5089 Re: Why Is Houdini Not Entered In The WCCC??] by [[Robert Houdart]], [[Computer Chess Forums|Open Chess Forum]], August 10, 2010</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=1647&start=10#p14724 Re: Computer Chess Biggest Liar] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|OpenChess Forum]], October 11, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?pid=427014#pid427014 Re: Interesting poll] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 15, 2012</ref> .
==Sources of Inspiration==
Robert Houdart on the origins of Houdini in [[CCC]], June 08, 2010 <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=354245&t=34770 Re: Purpose of Chess Engine Origins forum is...?] by [[Robert Houdart]], [[CCC]] (Computer Chess Club: Engine Origins, requires registration), June 08, 2010 in a reply to [[Jeremy Bernstein]]</ref>
From the start I have very clearly acknowledged the different sources of inspiration for Houdini ([[Ippolit|Ippo/Robbo]], [[Stockfish]] and [[Crafty]]) and have shown every respect for the hard work of others, be it on my web site, in the readme file, or in this forum ...
Houdini and the Ippo family have lots of high-level similarities, but zillions of low-level subtle differences.
Claims have been made that I "just changed a couple of resource strings", "made a cheap compile" or "grabbed some free code", but, in truth, none of you have any clue about the effort that was invested in Houdini.
It is funny that I would not be called a "real" chess engine author, when I am both a professional software developer and a reasonably strong chess player (peak 2280 rating), who has been writing chess engines for over 25 years now in a variety of programming languages.
It is sad that on the one hand you request that everybody demonstrates respect for the hard work of others, but on the other hand you seem to be unable to extend the same courtesy (or even the benefit of the doubt) to Houdini.
==Material Table==
The idea to index the [[Material Tables|material table]] in the same manner as Robbolito, with combined counters of queens, rooks, light and dark bishops, knights and pawns, and to calculate piece counters from that table-index by a sequence of mod/div operations by {2,2,3,3,2,2,2,2,3,3,9,9} might be considered obvious after studying the mentioned source code, and if applying that scheme, there is hardly anything to avoid a sequence of almost identical [[x86]] machine code with same constants for [[General Setwise Operations#ReciprocalMultiplication|reciprocal multiplication]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=34578 Houdini - a cheap compile of Ippo/Robo] by [[Lance Perkins]], [[CCC|CCC - Computer Chess Club: Engine Origins]], May 29, 2010 (requires login)</ref>.
==Strelka 5==
Robert Houdart on [[Strelka|Strelka 5]], December 04, 2011 <ref>[http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=436467&t=41272 Re: Komodo 4 on long time control] by [[Robert Houdart]], [[CCC]], December 04, 2011</ref>
Strelka 5 is Houdini 1.5 [https://en.wikipedia.org/wiki/Reverse_engineering RE], not Houdini 2. I share your fears, any #1 engine will be RE'd in a matter of months. For Houdini 1.5 it's taken about 6 months.
Reply by [[Richard Vida]] <ref>[http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=436498&t=41272 Re: Komodo 4 on long time control] by [[Richard Vida]], [[CCC]], December 04, 2011</ref>
You mean 6 months until [[Strelka]] has been released to public. You do not know how much time did [[Jury Osipov|Yuri Osipov]] spent on RE, neither when he did start his RE project. For me it took barely one week. As [[Milos Stanisavljevic|Milos S.]] pointed out <ref>[http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=435775&t=41236 Re: Lazy eval - test results] by [[Milos Stanisavljevic]], [[CCC]], December 01, 2011</ref> , you made RE very very easy because of starting your project from [[Robbolito]] codebase... Personally I see no problem with that (other than you not telling the truth).
=Release Dates=
* Houdini 1.0 : May 15, 2010
* Houdini 1.5 : December 15, 2010
* Houdini 2.0 : September 01, 2011
* Houdini 3 : October 15, 2012
* Houdini 4 : November 25, 2013
* Houdini 5: November 09, 2016
* Houdini 6: September 17, 2017
=Publications=
==Chess Engine==
* [[Diogo R. Ferreira]] ('''2012'''). ''Determining the Strength of Chess Players based on actual Play''. [[ICGA Journal#35_1|ICGA Journal, Vol. 35, No. 1]] » [[Playing Strength]]
* [[Arno Nickel]] ('''2012'''). ''[http://www.edition-marco-shop.de/epages/64079634.sf/de_DE/?ObjectPath=/Shops/64079634/Categories/Schachgeschehen/Computerschach Die schöne neue Welt der Schachengines]''. [http://www.zeitschriftschach.de/ SCHACH] 2,3,5,6 2012, [http://www.edition-marco-shop.de/WebRoot/Store14/Shops/64079634/5177/F0A3/C389/D0DD/3A71/C0A8/2935/25F6/Die_schoene_neue_Welt_der_Schachengines.pdf pdf] (German) <ref>Part 1 covers [[Houdini]], [[Rybka]], [[Komodo]], [[Stockfish]], [[Critter]], [[Naum]], [[Chiron]] and [[Spike]]</ref>
* [[Matej Guid]], [[Ivan Bratko]] ('''2012'''). ''Detecting Fortresses in Chess''. [http://ev.fe.uni-lj.si/ Elektrotehniški vestnik], Vol. 79, Nos. 1-2, [https://ailab.si/matej/doc/Detecting_Fortresses_in_Chess.pdf pdf] » [[Fortress]], [[Rybka]], [[Houdini]]
* [[Diogo R. Ferreira]] ('''2013'''). ''The Impact of the Search Depth on Chess Playing Strength''. [[ICGA Journal#36_2|ICGA Journal, Vol. 36, No. 2]]
==Harry Houdini==
* [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini], et al. ('''1906, 2012'''). ''[https://books.google.com/books?id=j5_XHZImTqcC&printsec=frontcover The Right Way to Do Wrong: An Exposé of Successful Criminals]''. [http://de.wikipedia.org/wiki/CreateSpace.com CreateSpace], [http://www.amazon.com/The-Right-Way-Wrong-Successful/dp/1481157647 amazon.com]
: [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini] ('''2007'''). ''[https://archive.org/details/right_way_to_do_wrong_lah_librivox The Right Way to Do Wrong]''. [https://en.wikipedia.org/wiki/LibriVox Librivox audio recording] from the [https://en.wikipedia.org/wiki/Internet_Archive Internet Archive]
* [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini], [http://www.loc.gov/rr/rarebook/coll/122.html Harry Houdini Collection] ('''1908'''). ''[https://archive.org/details/unmaskingrobert00houdgoog The unmasking of Robert-Houdin]''. New York : Publishers Printing Co. <ref>[https://en.wikipedia.org/wiki/Jean_Eug%C3%A8ne_Robert-Houdin Jean Eugène Robert-Houdin - Wikipedia]</ref>
* [https://en.wikipedia.org/wiki/Walter_B._Gibson Walter Brown Gibson], [http://archives.library.illinois.edu/archon/?p=creators/creator&id=2380 Morris N. Young] ('''1953'''). ''[[https:\\books.google.com/books?id=WqAlWYtemkIC|Houdini on Magic]]''. [https://en.wikipedia.org/wiki/Dover_Publications Dover Publications]
=Forum Posts=
==2010 ...==
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=348905&t=34326 Re: Costeff Study 1979] by [[Robert Houdart]], [[CCC]], May 16, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=34578 Houdini - a cheap compile of Ippo/Robo] by [[Lance Perkins]], [[CCC|CCC - Computer Chess Club: Engine Origins]], May 29, 2010 (requires login)
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=354023&t=34673 Re: question on draw evaluation] by [[Robert Houdart]], [[CCC]], June 07, 2010 » [[Draw Evaluation]]
* [http://www.talkchess.com/forum/viewtopic.php?t=35453 Houdini 1.03 is available] by [[Robert Houdart]], [[CCC]], July 15, 2010
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=361912&t=35338 Re: Mate in 17 revisited] by [[Robert Houdart]], [[CCC]], July 16, 2010 » [[Zugzwang]]
* [http://www.talkchess.com/forum/viewtopic.php?t=35469 Houdini 1.03a bug-fix is available] by [[Robert Houdart]], [[CCC]], July 17, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=35497 Houdini 1.03a tests] by [[Harun Taner]], [[CCC]], July 18, 2010
* [http://www.open-chess.org/viewtopic.php?f=3&t=534 Why Is Houdini Not Entered In The WCCC??] by Sean Evans, [[Computer Chess Forums|Open Chess Forum]], August 03, 2010
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=368026&t=35858 Re: Plain and fancy magic on modern hardware] by [[Robert Houdart]], [[CCC]], August 26, 2010 » [[Magic Bitboards]]
* [http://www.talkchess.com/forum/viewtopic.php?t=36886 Gaviota EGTB in Houdini 1.5 + contacting Eugene Nalimov] by [[Robert Houdart]], [[CCC]], December 01, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37091 Houdini 1.5 is released] by [[Robert Houdart]], [[CCC]], December 15, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37175 Houdini 1.5 with Large Page support and 8-cores for w32] by [[Robert Houdart]], [[CCC]], December 19, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37206 Houdini 1.5: one mystery/question] by [[Jouni Uski]], [[CCC]], December 21, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37311 Houdini and Chessbase GUI engine matches] by [[Robert Houdart]], [[CCC]], December 27, 2010
'''2011'''
* [http://open-chess.org/viewtopic.php?f=7&t=992 Houdini Engine Origins] by [[Jeremy Bernstein]], [[Computer Chess Forums|OpenChess Forum]], January 18, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=38052 a Telltale position] by [[Larry Kaufman]], [[CCC]], 12 February, 2011
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=396662&t=38198 Re: Why are the Ippo derivative stronger than Stockfish?] by [[Richard Vida]], [[CCC]], 25 February, 2011
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=400730&t=38535 Re: Hash usage percent display (in Arena)] by [[Robert Houdart]], [[CCC]], March 24, 2011
* [http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=406820&t=38932 Re: Houdini, Fire, IvanHoe, (and Rybka?) are 'clones'...?] by [[Jury Osipov]], [[CCC]], May 12, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39812 Some news about Houdini 2.0] by [[Robert Houdart]], [[CCC]], July 22, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40245 Houdini 2 is released] by [[Robert Houdart]], [[CCC]], September 02, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40673 Houdini 2 Aquarium released] by [[Robert Houdart]], [[CCC]], October 09, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1647 Computer Chess Biggest Liar] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|OpenChess Forum]], October 09, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40709 how far is too far: houdini for sell?] by Joseph, [[CCC]], October 11, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40728 Houdini with 1:1 Robbolito-code?] by [[Dr. Alexander Schmidt]], [[CCC]], October 12, 2011
: [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=428534&t=40728 Re: Houdini with 1:1 Robbolito-code?] by [[Norman Schmidt]], [[CCC]], October 12, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40777 Strelka 5 by Yuriy Osipov] by Slavik Pavloff, [[CCC]], October 15, 2011 » [[Strelka]]
* [http://www.talkchess.com/forum/viewtopic.php?t=41221 New:Houdini 2 Chess Benchmarks are Acceptable!] by [[Sedat Canbaz]], [[CCC]], November 26, 2011
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=436153&t=41313 Re: Any plans for Houdini 3?] by [[Robert Houdart]], [[CCC]], December 03, 2011
* [http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=436498&t=41272 Re: Komodo 4 on long time control] by [[Richard Vida]], [[CCC]], December 04, 2011 » [[Komodo]], [[Strelka]]
* [http://www.talkchess.com/forum/viewtopic.php?t=41375 Houdini 2.0c - Mate in 1 bug] by [[Árpád Rusz]], [[CCC]], December 08, 2011
'''2012'''
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?pid=427014#pid427014 Re: Interesting poll] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 15, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45624 Houdini 3 reducing the depth feature] by Maurizio Maglio, [[CCC]], October 17, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45697 Houdini 3 does not behave the same in 64-bit and 32-bit] by [[Ernest Bonnem]], [[CCC]], October 23, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45768 houdini3 search and mate scores] by [[Uri Blass]], [[CCC]], October 29, 2012 » [[Score#MateScores|Mate Scores]]
* [http://www.talkchess.com/forum/viewtopic.php?t=45816 Houdini 3 update does behave the same in 64-bit and 32-bit] by [[Ernest Bonnem]], [[CCC]], November 01, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45948 What is stronger than Houdini 3 for what?] by S.Taylor, [[CCC]], November 11, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45961 Houdini 3 tests (8cpu)] by [[Harun Taner]], [[CCC]], November 12, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=46019 The scaling of Houdini 3 and Komodo 5] by [[Kai Laskos]], [[CCC]], November 16, 2012 » [[Komodo]]
* [http://forum.computerschach.de/cgi-bin/mwf/topic_show.pl?tid=5184 Houdini 3-Houdini 3: Nutzen der Bedenkzeitverlängerung] by Patrick Götz, [[Computer Chess Forums|CSS-Forum]], December 07, 2012 (German) » [[Depth#DiminishingReturns|Diminishing Returns]]
* [http://www.talkchess.com/forum/viewtopic.php?t=46182 Houdini 3 the same in 64-bit and 32-bit: well, not quite?] by [[Ernest Bonnem]], [[CCC]], November 28, 2012
'''2013'''
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=26392 10 Lessons to be Learned from todays Top Engines] by Josef, [[Computer Chess Forums|Rybka Forum]], January 03, 2013 » [[Komodo]], [[Stockfish]]
* [http://www.talkchess.com/forum/viewtopic.php?t=46879 eval scale in Houdini] by [[Rein Halbersma]], [[CCC]], January 14, 2013 » [[Evaluation]]
* [http://www.talkchess.com/forum/viewtopic.php?t=48733 Scaling at 2x nodes (or doubling time control)] by [[Kai Laskos]], [[CCC]], July 23, 2013 » [[Match Statistics#DoublingTC|Doubling TC]], [[Depth#DiminishingReturns|Diminishing Returns]], [[Playing Strength]], [[Houdini]]
* [http://www.talkchess.com/forum/viewtopic.php?t=50224 Houdini 4 has been released] by [[Robert Houdart]], [[CCC]], November 25, 2013
* [http://www.talkchess.com/forum/viewtopic.php?t=50266 Houdini, much weaker engines, and Arpad Elo] by [[Kai Laskos]], [[CCC]], November 29, 2013 » [[Match Statistics]], [[Pawn Advantage, Win Percentage, and ELO]] <ref>[https://en.wikipedia.org/wiki/Arpad_Elo Arpad Elo - Wikipedia]</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=50304 IPON results for Houdini 4] by [[Robert Houdart]], [[CCC]], December 02, 2013 » [[IPON]]
* [http://www.talkchess.com/forum/viewtopic.php?t=50340 Be careful where you buy Houdini 4, or you could get burned] by [[Tom Likens]], [[CCC]], December 05, 2013
'''2014'''
* [http://www.talkchess.com/forum/viewtopic.php?t=51107 Houdini 3/4?] by Jason Coombs, [[CCC]], January 30, 2014
* [http://www.talkchess.com/forum/viewtopic.php?p=570955 Threads factor: Komodo, Houdini, Stockfish and Zappa] by [[Andreas Strangmüller]], [[CCC]], May 17, 2014 » [[Thread]], [[Komodo]], [[Houdini]], [[Stockfish]], [[Zappa]]
==2015 ...==
* [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]]
'''2016'''
* [http://www.talkchess.com/forum/viewtopic.php?t=59849 Houdini 5 in TCEC] by John Wentworth, [[CCC]], April 13, 2016 » [[TCEC Season 9]] <ref>[http://www.chessdom.com/houdini-5-to-participate-in-tcec-season-9/ Houdini 5 to participate in TCEC Season 9], [[Chessdom]], April 13, 2016</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=61357 Houdini 5 dev in TCEC] by [[Jouni Uski]], [[CCC]], September 08, 2016 » [[TCEC Season 9]]
* [http://www.talkchess.com/forum/viewtopic.php?t=61611 New Houdini] by [[Dann Corbit]], [[CCC]], October 05, 2016
* [http://www.talkchess.com/forum/viewtopic.php?t=62035 Houdini 5 has been released] by [[Robert Houdart]], [[CCC]], November 09, 2016
* [http://www.talkchess.com/forum/viewtopic.php?t=62366 chessbase houdini is out but...] by Stavros Atmatzidis, [[CCC]], December 03, 2016
'''2017'''
* [http://www.talkchess.com/forum/viewtopic.php?t=65211 Houdini 6 has been released] by [[Robert Houdart]], [[CCC]], September 18, 2017
* [http://www.talkchess.com/forum/viewtopic.php?t=65288 Scaling from FGRL results with top 3 engines] by [[Kai Laskos]], [[CCC]], September 26, 2017 » [[FGRL]], [[Komodo]], [[Stockfish]]
=External Links=
==Chess Engine==
* [https://en.wikipedia.org/wiki/Houdini_%28chess%29 Houdini (chess) from Wikipedia]
===Purchase===
* [http://www.cruxis.com/chess/houdini.htm Houdini Chess Engine]
* [https://shop.chessbase.com/en/products/houdini_6_pro_multiprocessor_version Houdini 6 Pro] [[ChessBase|ChessBase Shop]], September 17, 2017
* [https://shop.chessbase.com/en/products/houdini_5_pro_multiprocessor_version Houdini 5 Pro] [[ChessBase|ChessBase Shop]], December 02, 2016
* [https://shop.chessok.com/index.php?main_page=index&cPath=7_56 Houdini 6 and Aquarium 2018], [[ChessOK]] » [[Aquarium]]
===Interviews===
* [http://chess-king.com/images/kingintromaterials/HoudartInterview/InterviewHoudiniA.pdf Interview of Robert Houdart, the Creator of the Strongest Chess Engine in the world: Houdini] (pdf), [http://chess-king.com/ chess-king.com]
* [https://en.chessbase.com/post/houdini-3-the-world-s-strongest-che-engine-in-the-fritz-interface Houdini 3 – the world's strongest chess engine in the Fritz interface - Interview with Robert Houdart, author of Houdini], [[ChessBase|ChessBase News]], October 29, 2012
* [http://www.chessdom.com/robert-houdart-on-houdini-5-dev-in-tcec/ Robert Houdart on Houdini 5 dev in TCEC], [[Chessdom]], August 25, 2016 » [[TCEC Season 9]]
* [http://www.chessdom.com/interview-with-robert-houdart-mark-lefler-and-gm-larry-kaufman/ Interview with Robert Houdart, Mark Lefler and GM Larry Kaufman] by [[Nelson Hernandez]], [[Chessdom]], November 23, 2017 » [[TCEC Season 10]]
* [http://www.chessdom.com/interview-with-robert-houdart-author-of-the-champion-engine-houdini/ Interview with Robert Houdart, author of the champion engine Houdini], [[Chessdom]], December 08, 2017
===Reports===
* [https://en.chessbase.com/post/neu-houdini-6 New: Houdini 6 | ChessBase], [[ChessBase|ChessBase News]], October 18, 2017
* [https://en.chessbase.com/post/houdini-3-the-new-king-of-the-block-part-one- Houdini 3: the new king of the block (part one)] by [[Albert Silver]], [[ChessBase|ChessBase News]], November 13, 2012
* [https://en.chessbase.com/post/houdini-3-analyzing-in-the-cloud-part-two- Houdini 3: Analyzing in the cloud (part two)] by [[Albert Silver]], [[ChessBase|ChessBase News]], November 17, 2012
* [https://en.chessbase.com/post/houdini-4-the-800-pound-gorilla-2 Houdini 4: the 800-pound gorilla], [[ChessBase|ChessBase News]], December 07, 2013
* [https://thetech.com/2014/01/15/chess-v133-n62 One chess champion per laptop] by [http://www.mit.edu/~roberto/ Roberto Perez-Franco], [[Massachusetts Institute of Technology|MIT's]] [https://en.wikipedia.org/wiki/The_Tech_%28newspaper%29 The Tech], January 15, 2014 » [[TCEC Season 5]]
* [http://www.chessdom.com/houdini-5-to-participate-in-tcec-season-9/ Houdini 5 to participate in TCEC Season 9], [[Chessdom]], April 13, 2016 » [[TCEC Season 9]]
* [https://en.chessbase.com/post/houdini5tacticalmode Houdini 5's Tactical Mode: Releasing the Kraken] by [[Albert Silver]], [[ChessBase|ChessBase News]], December 08, 2016
* [https://en.chessbase.com/post/fair-play-in-engine-match Fair play in engine chess], [[ChessBase|ChessBase News]], December 30, 2016 » [[Houdini#5|Houdini 5]], [[Komodo#10|Komodo 10]]
* [https://en.chessbase.com/post/tcec-superfinal-houdini-vs-komodo TCEC: Superfinal Houdini vs Komodo] by [[Stephan Oliver Platz]], [[ChessBase|ChessBase News]], November 23, 2017 » [[TCEC Season 10]]
* [http://www.chessdom.com/houdini-is-tcec-season-10-champion/ Houdini is TCEC Season 10 champion!], [[Chessdom]], December 07, 2017
* [https://en.chessbase.com/post/houdini-wins-the-tcec-superfinal Houdini wins TCEC Superfinal] by [[Stephan Oliver Platz]], [[ChessBase|ChessBase News]], December 13, 2017 » [[TCEC Season 10]]
===Rating Lists===
* [http://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Houdini&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 Houdini] in [[CCRL|CCRL 40/40]]
* [http://www.computerchess.org.uk/ccrl/4040/cgi/engine_details.cgi?match_length=30&each_game=1&print=Details&each_game=1&eng=Houdini%206%2064-bit%204CPU#Houdini_6_64-bit_4CPU Houdini 6 64-bit 4CPU] in [[CCRL|CCRL 40/40]]
==Harry Houdini==
* [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini from Wikipedia]
* [https://www.thegreatharryhoudini.com/ Harry Houdini - The Life of Harry Houdini]
* [http://www.loc.gov/rr/rarebook/coll/122.html Harry Houdini Collection]
* [https://www.biography.com/people/harry-houdini-40056 Harry Houdini Biography - Facts, Birthday, Life Story - Biography.com]
=References=
<references />
'''[[Engines|Up one level]]'''
[[Category:UCI]]
[[Category:Commercial]]
[[Category:Legend]]
[[Category:Magic]]
[[FILE:Grim game.jpg|border|right|thumb|240px| [https://en.wikipedia.org/wiki/Harry_Houdini Houdini] in "[https://en.wikipedia.org/wiki/The_Grim_Game The Grim Game]" <ref>[https://en.wikipedia.org/wiki/The_Grim_Game The Grim Game] a 1919 [https://en.wikipedia.org/wiki/Silent_film silent film] starring [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini]</ref> ]]
'''Houdini''',<br/>
a chess engine by [[Robert Houdart]], which appeared in 2010 as closed source engine, free for non-commercial use. In January 2011, Houdini '''1.5''' was leading [[Ingo Bauer|Ingo Bauer's]] [[IPON]] [[Engine Rating Lists|rating list]] <ref>[http://www.inwoba.de/News2009_2011.7z IPON-Rating-List Archive 2009/2010/2011] by [[Ingo Bauer]]</ref> . Houdini '''2''', released in September 2011, is commercial and bundled with a number of [[ChessOK]] products, such as [[Aquarium]], [[Chess Assistant]] <ref>[http://chessok.com/?p=25808 Houdini 2 Aquarium products family has been released!], [[ChessOK]], October 07, 2011</ref>, and since December 2011, [[Chess King]] <ref>[http://chessok.com/?p=26441 Chess King Released], [[ChessOK]], December 14, 2011</ref>. Houdini 1.5a remains available as a free download <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=421920&t=40245 Re: Houdini 2 is released] by [[Robert Houdart]], [[CCC]], September 02, 2011</ref>. Houdini '''3''', released in October 2012, has further improved by more than 50 Elo points <ref>[http://www.inwoba.de/index.html IPON-Rating-List, 2012.10.17] by [[Ingo Bauer]]</ref> . According to its author, Houdini 3 applies a accelerated [[Principal Variation Search|principal variation search]], also dubbed "Smart" [[Fail-High]]. If a different move becomes [[Best Move|best]] at very high [[Depth|search depths]] at the [[Root|root]], re-searches to determine its [[Exact Score|exact score]] and the new [[Principal Variation|principal variation]] are done faster due to a reduced search depth, presumably in conjunction with [[Extensions|extensions]] along the PV <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=488422&t=45624 Re: Houdini 3 reducing the depth feature] by [[Robert Houdart]], [[CCC]], October 19, 2012</ref> . Since November 2012, Houdini 3 is available as [[ChessBase]] engine <ref>[http://chessbase-shop.com/en/products/houdini_3_standard_multiprocessor_version Houdini 3 Standard multiprocessor version], [[ChessBase|ChessBase Shop]]</ref> . Houdini '''4''', released in November 2013, was about 50 Elo stronger than its predecessor, and features 6-men [[Syzygy Bases|Syzygy bases]].
<span id="5"></span>
=Houdini 5=
Released about three years after the previous version, in November 2016, '''Houdini 5''' is vastly improved being about 200 Elo stronger than Houdini 4. It has a completely rewritten [[Evaluation|evaluation]] with more aggressive [[King Safety|king safety]] and sophisticated [[Mobility|piece mobility]], features a more [[Selectivity|selective]] [[Search|search]], exploring critical variations significantly deeper, and for hardware with multiple processors, [[Lazy SMP]]. Houdini '''5 Pro''' supports up to 128 [[Thread|threads]], up to 128 GiB of [[Shared Hash Table|hash memory]], [[Memory#HugePages|large memory pages]], [[NUMA|NUMA-architecture]], and [[Nalimov Tablebases|Nalimov tablebases]] to find the shortest path to [[Checkmate|mate]].
A development version of Houdini 5 qualified for [[TCEC Season 9#Superfinal|TCEC Season 9 Superfinal]], and even won the [[TCEC Season 9#Rapid|TCEC Season 9 Rapid tournament]]. The final release version of Houdini 5 is about 30 Elo stronger than the engine that played in the TCEC tournament so far. But that was apparently not enough for [[Stockfish|Stockfish 8]] in long time control matches - Houdini 5 lost the 100 game [[TCEC Season 9#Superfinal|Superfinal]] with 45½ - 54½.
<span id="6"></span>
=Houdini 6=
Released in September 2017, Houdini '''6''' again improved in [[Search|search]] and [[Evaluation|evaluation]] to add another 50-60 Elo in [[Playing Strength|strength]], which roughly corresponds to doubling the computational power of the computer <ref>[http://www.cruxis.com/chess/houdini.htm Houdini Chess Engine]</ref>. '''Houdini 6.03''' won the [[TCEC Season 10#Superfinal|TCEC Season 10 Superfinal]] versus [[Komodo|Komodo 1970.00]], a successor of Komodo 11, with '''53 - 47''' (+15=76-9) <ref>[http://www.chessdom.com/houdini-is-tcec-season-10-champion/ Houdini is TCEC Season 10 champion!], [[Chessdom]], December 07, 2017</ref> <ref>[http://www.chessdom.com/interview-with-robert-houdart-author-of-the-champion-engine-houdini/ Interview with Robert Houdart, author of the champion engine Houdini], [[Chessdom]], December 08, 2017</ref>.
=Houdini's Origin=
Robert Houdart claims his engine is original <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=534&start=20#p4798 Re: Why Is Houdini Not Entered In The WCCC??] by [[Robert Houdart]], [[Computer Chess Forums|Open Chess Forum]], August 04, 2010</ref>, and admits taking ideas from the open source programs [[Ippolit|Ippolit/Robbolito]], [[Stockfish]] and [[Crafty]] <ref>[http://www.cruxis.com/chess/houdini.htm Houdini Chess Engine - Acknowledgements]</ref> . Other programmers and forum members raised suspicions that Robert took ideas from the controversial Ippolit/Robbolito source code too literally as initial base of his program <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=534&start=40#p5084 Re: Why Is Houdini Not Entered In The WCCC??] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|Open Chess Forum]], August 09, 2010</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=534&start=40#p5089 Re: Why Is Houdini Not Entered In The WCCC??] by [[Robert Houdart]], [[Computer Chess Forums|Open Chess Forum]], August 10, 2010</ref> <ref>[http://www.open-chess.org/viewtopic.php?f=3&t=1647&start=10#p14724 Re: Computer Chess Biggest Liar] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|OpenChess Forum]], October 11, 2011</ref> <ref>[http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?pid=427014#pid427014 Re: Interesting poll] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 15, 2012</ref> .
==Sources of Inspiration==
Robert Houdart on the origins of Houdini in [[CCC]], June 08, 2010 <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=354245&t=34770 Re: Purpose of Chess Engine Origins forum is...?] by [[Robert Houdart]], [[CCC]] (Computer Chess Club: Engine Origins, requires registration), June 08, 2010 in a reply to [[Jeremy Bernstein]]</ref>
From the start I have very clearly acknowledged the different sources of inspiration for Houdini ([[Ippolit|Ippo/Robbo]], [[Stockfish]] and [[Crafty]]) and have shown every respect for the hard work of others, be it on my web site, in the readme file, or in this forum ...
Houdini and the Ippo family have lots of high-level similarities, but zillions of low-level subtle differences.
Claims have been made that I "just changed a couple of resource strings", "made a cheap compile" or "grabbed some free code", but, in truth, none of you have any clue about the effort that was invested in Houdini.
It is funny that I would not be called a "real" chess engine author, when I am both a professional software developer and a reasonably strong chess player (peak 2280 rating), who has been writing chess engines for over 25 years now in a variety of programming languages.
It is sad that on the one hand you request that everybody demonstrates respect for the hard work of others, but on the other hand you seem to be unable to extend the same courtesy (or even the benefit of the doubt) to Houdini.
==Material Table==
The idea to index the [[Material Tables|material table]] in the same manner as Robbolito, with combined counters of queens, rooks, light and dark bishops, knights and pawns, and to calculate piece counters from that table-index by a sequence of mod/div operations by {2,2,3,3,2,2,2,2,3,3,9,9} might be considered obvious after studying the mentioned source code, and if applying that scheme, there is hardly anything to avoid a sequence of almost identical [[x86]] machine code with same constants for [[General Setwise Operations#ReciprocalMultiplication|reciprocal multiplication]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=34578 Houdini - a cheap compile of Ippo/Robo] by [[Lance Perkins]], [[CCC|CCC - Computer Chess Club: Engine Origins]], May 29, 2010 (requires login)</ref>.
==Strelka 5==
Robert Houdart on [[Strelka|Strelka 5]], December 04, 2011 <ref>[http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=436467&t=41272 Re: Komodo 4 on long time control] by [[Robert Houdart]], [[CCC]], December 04, 2011</ref>
Strelka 5 is Houdini 1.5 [https://en.wikipedia.org/wiki/Reverse_engineering RE], not Houdini 2. I share your fears, any #1 engine will be RE'd in a matter of months. For Houdini 1.5 it's taken about 6 months.
Reply by [[Richard Vida]] <ref>[http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=436498&t=41272 Re: Komodo 4 on long time control] by [[Richard Vida]], [[CCC]], December 04, 2011</ref>
You mean 6 months until [[Strelka]] has been released to public. You do not know how much time did [[Jury Osipov|Yuri Osipov]] spent on RE, neither when he did start his RE project. For me it took barely one week. As [[Milos Stanisavljevic|Milos S.]] pointed out <ref>[http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=435775&t=41236 Re: Lazy eval - test results] by [[Milos Stanisavljevic]], [[CCC]], December 01, 2011</ref> , you made RE very very easy because of starting your project from [[Robbolito]] codebase... Personally I see no problem with that (other than you not telling the truth).
=Release Dates=
* Houdini 1.0 : May 15, 2010
* Houdini 1.5 : December 15, 2010
* Houdini 2.0 : September 01, 2011
* Houdini 3 : October 15, 2012
* Houdini 4 : November 25, 2013
* Houdini 5: November 09, 2016
* Houdini 6: September 17, 2017
=Publications=
==Chess Engine==
* [[Diogo R. Ferreira]] ('''2012'''). ''Determining the Strength of Chess Players based on actual Play''. [[ICGA Journal#35_1|ICGA Journal, Vol. 35, No. 1]] » [[Playing Strength]]
* [[Arno Nickel]] ('''2012'''). ''[http://www.edition-marco-shop.de/epages/64079634.sf/de_DE/?ObjectPath=/Shops/64079634/Categories/Schachgeschehen/Computerschach Die schöne neue Welt der Schachengines]''. [http://www.zeitschriftschach.de/ SCHACH] 2,3,5,6 2012, [http://www.edition-marco-shop.de/WebRoot/Store14/Shops/64079634/5177/F0A3/C389/D0DD/3A71/C0A8/2935/25F6/Die_schoene_neue_Welt_der_Schachengines.pdf pdf] (German) <ref>Part 1 covers [[Houdini]], [[Rybka]], [[Komodo]], [[Stockfish]], [[Critter]], [[Naum]], [[Chiron]] and [[Spike]]</ref>
* [[Matej Guid]], [[Ivan Bratko]] ('''2012'''). ''Detecting Fortresses in Chess''. [http://ev.fe.uni-lj.si/ Elektrotehniški vestnik], Vol. 79, Nos. 1-2, [https://ailab.si/matej/doc/Detecting_Fortresses_in_Chess.pdf pdf] » [[Fortress]], [[Rybka]], [[Houdini]]
* [[Diogo R. Ferreira]] ('''2013'''). ''The Impact of the Search Depth on Chess Playing Strength''. [[ICGA Journal#36_2|ICGA Journal, Vol. 36, No. 2]]
==Harry Houdini==
* [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini], et al. ('''1906, 2012'''). ''[https://books.google.com/books?id=j5_XHZImTqcC&printsec=frontcover The Right Way to Do Wrong: An Exposé of Successful Criminals]''. [http://de.wikipedia.org/wiki/CreateSpace.com CreateSpace], [http://www.amazon.com/The-Right-Way-Wrong-Successful/dp/1481157647 amazon.com]
: [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini] ('''2007'''). ''[https://archive.org/details/right_way_to_do_wrong_lah_librivox The Right Way to Do Wrong]''. [https://en.wikipedia.org/wiki/LibriVox Librivox audio recording] from the [https://en.wikipedia.org/wiki/Internet_Archive Internet Archive]
* [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini], [http://www.loc.gov/rr/rarebook/coll/122.html Harry Houdini Collection] ('''1908'''). ''[https://archive.org/details/unmaskingrobert00houdgoog The unmasking of Robert-Houdin]''. New York : Publishers Printing Co. <ref>[https://en.wikipedia.org/wiki/Jean_Eug%C3%A8ne_Robert-Houdin Jean Eugène Robert-Houdin - Wikipedia]</ref>
* [https://en.wikipedia.org/wiki/Walter_B._Gibson Walter Brown Gibson], [http://archives.library.illinois.edu/archon/?p=creators/creator&id=2380 Morris N. Young] ('''1953'''). ''[[https:\\books.google.com/books?id=WqAlWYtemkIC|Houdini on Magic]]''. [https://en.wikipedia.org/wiki/Dover_Publications Dover Publications]
=Forum Posts=
==2010 ...==
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=348905&t=34326 Re: Costeff Study 1979] by [[Robert Houdart]], [[CCC]], May 16, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=34578 Houdini - a cheap compile of Ippo/Robo] by [[Lance Perkins]], [[CCC|CCC - Computer Chess Club: Engine Origins]], May 29, 2010 (requires login)
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=354023&t=34673 Re: question on draw evaluation] by [[Robert Houdart]], [[CCC]], June 07, 2010 » [[Draw Evaluation]]
* [http://www.talkchess.com/forum/viewtopic.php?t=35453 Houdini 1.03 is available] by [[Robert Houdart]], [[CCC]], July 15, 2010
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=361912&t=35338 Re: Mate in 17 revisited] by [[Robert Houdart]], [[CCC]], July 16, 2010 » [[Zugzwang]]
* [http://www.talkchess.com/forum/viewtopic.php?t=35469 Houdini 1.03a bug-fix is available] by [[Robert Houdart]], [[CCC]], July 17, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=35497 Houdini 1.03a tests] by [[Harun Taner]], [[CCC]], July 18, 2010
* [http://www.open-chess.org/viewtopic.php?f=3&t=534 Why Is Houdini Not Entered In The WCCC??] by Sean Evans, [[Computer Chess Forums|Open Chess Forum]], August 03, 2010
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=368026&t=35858 Re: Plain and fancy magic on modern hardware] by [[Robert Houdart]], [[CCC]], August 26, 2010 » [[Magic Bitboards]]
* [http://www.talkchess.com/forum/viewtopic.php?t=36886 Gaviota EGTB in Houdini 1.5 + contacting Eugene Nalimov] by [[Robert Houdart]], [[CCC]], December 01, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37091 Houdini 1.5 is released] by [[Robert Houdart]], [[CCC]], December 15, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37175 Houdini 1.5 with Large Page support and 8-cores for w32] by [[Robert Houdart]], [[CCC]], December 19, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37206 Houdini 1.5: one mystery/question] by [[Jouni Uski]], [[CCC]], December 21, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=37311 Houdini and Chessbase GUI engine matches] by [[Robert Houdart]], [[CCC]], December 27, 2010
'''2011'''
* [http://open-chess.org/viewtopic.php?f=7&t=992 Houdini Engine Origins] by [[Jeremy Bernstein]], [[Computer Chess Forums|OpenChess Forum]], January 18, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=38052 a Telltale position] by [[Larry Kaufman]], [[CCC]], 12 February, 2011
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=396662&t=38198 Re: Why are the Ippo derivative stronger than Stockfish?] by [[Richard Vida]], [[CCC]], 25 February, 2011
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=400730&t=38535 Re: Hash usage percent display (in Arena)] by [[Robert Houdart]], [[CCC]], March 24, 2011
* [http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=406820&t=38932 Re: Houdini, Fire, IvanHoe, (and Rybka?) are 'clones'...?] by [[Jury Osipov]], [[CCC]], May 12, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=39812 Some news about Houdini 2.0] by [[Robert Houdart]], [[CCC]], July 22, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40245 Houdini 2 is released] by [[Robert Houdart]], [[CCC]], September 02, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40673 Houdini 2 Aquarium released] by [[Robert Houdart]], [[CCC]], October 09, 2011
* [http://www.open-chess.org/viewtopic.php?f=3&t=1647 Computer Chess Biggest Liar] by [[Franklin Titus|kingliveson]], [[Computer Chess Forums|OpenChess Forum]], October 09, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40709 how far is too far: houdini for sell?] by Joseph, [[CCC]], October 11, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40728 Houdini with 1:1 Robbolito-code?] by [[Dr. Alexander Schmidt]], [[CCC]], October 12, 2011
: [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=428534&t=40728 Re: Houdini with 1:1 Robbolito-code?] by [[Norman Schmidt]], [[CCC]], October 12, 2011
* [http://www.talkchess.com/forum/viewtopic.php?t=40777 Strelka 5 by Yuriy Osipov] by Slavik Pavloff, [[CCC]], October 15, 2011 » [[Strelka]]
* [http://www.talkchess.com/forum/viewtopic.php?t=41221 New:Houdini 2 Chess Benchmarks are Acceptable!] by [[Sedat Canbaz]], [[CCC]], November 26, 2011
* [http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=436153&t=41313 Re: Any plans for Houdini 3?] by [[Robert Houdart]], [[CCC]], December 03, 2011
* [http://talkchess.com/forum/viewtopic.php?topic_view=threads&p=436498&t=41272 Re: Komodo 4 on long time control] by [[Richard Vida]], [[CCC]], December 04, 2011 » [[Komodo]], [[Strelka]]
* [http://www.talkchess.com/forum/viewtopic.php?t=41375 Houdini 2.0c - Mate in 1 bug] by [[Árpád Rusz]], [[CCC]], December 08, 2011
'''2012'''
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?pid=427014#pid427014 Re: Interesting poll] by [[Ed Schroder|Rebel]], [[Computer Chess Forums|Rybka Forum]], July 15, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45624 Houdini 3 reducing the depth feature] by Maurizio Maglio, [[CCC]], October 17, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45697 Houdini 3 does not behave the same in 64-bit and 32-bit] by [[Ernest Bonnem]], [[CCC]], October 23, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45768 houdini3 search and mate scores] by [[Uri Blass]], [[CCC]], October 29, 2012 » [[Score#MateScores|Mate Scores]]
* [http://www.talkchess.com/forum/viewtopic.php?t=45816 Houdini 3 update does behave the same in 64-bit and 32-bit] by [[Ernest Bonnem]], [[CCC]], November 01, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45948 What is stronger than Houdini 3 for what?] by S.Taylor, [[CCC]], November 11, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=45961 Houdini 3 tests (8cpu)] by [[Harun Taner]], [[CCC]], November 12, 2012
* [http://www.talkchess.com/forum/viewtopic.php?t=46019 The scaling of Houdini 3 and Komodo 5] by [[Kai Laskos]], [[CCC]], November 16, 2012 » [[Komodo]]
* [http://forum.computerschach.de/cgi-bin/mwf/topic_show.pl?tid=5184 Houdini 3-Houdini 3: Nutzen der Bedenkzeitverlängerung] by Patrick Götz, [[Computer Chess Forums|CSS-Forum]], December 07, 2012 (German) » [[Depth#DiminishingReturns|Diminishing Returns]]
* [http://www.talkchess.com/forum/viewtopic.php?t=46182 Houdini 3 the same in 64-bit and 32-bit: well, not quite?] by [[Ernest Bonnem]], [[CCC]], November 28, 2012
'''2013'''
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=26392 10 Lessons to be Learned from todays Top Engines] by Josef, [[Computer Chess Forums|Rybka Forum]], January 03, 2013 » [[Komodo]], [[Stockfish]]
* [http://www.talkchess.com/forum/viewtopic.php?t=46879 eval scale in Houdini] by [[Rein Halbersma]], [[CCC]], January 14, 2013 » [[Evaluation]]
* [http://www.talkchess.com/forum/viewtopic.php?t=48733 Scaling at 2x nodes (or doubling time control)] by [[Kai Laskos]], [[CCC]], July 23, 2013 » [[Match Statistics#DoublingTC|Doubling TC]], [[Depth#DiminishingReturns|Diminishing Returns]], [[Playing Strength]], [[Houdini]]
* [http://www.talkchess.com/forum/viewtopic.php?t=50224 Houdini 4 has been released] by [[Robert Houdart]], [[CCC]], November 25, 2013
* [http://www.talkchess.com/forum/viewtopic.php?t=50266 Houdini, much weaker engines, and Arpad Elo] by [[Kai Laskos]], [[CCC]], November 29, 2013 » [[Match Statistics]], [[Pawn Advantage, Win Percentage, and ELO]] <ref>[https://en.wikipedia.org/wiki/Arpad_Elo Arpad Elo - Wikipedia]</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=50304 IPON results for Houdini 4] by [[Robert Houdart]], [[CCC]], December 02, 2013 » [[IPON]]
* [http://www.talkchess.com/forum/viewtopic.php?t=50340 Be careful where you buy Houdini 4, or you could get burned] by [[Tom Likens]], [[CCC]], December 05, 2013
'''2014'''
* [http://www.talkchess.com/forum/viewtopic.php?t=51107 Houdini 3/4?] by Jason Coombs, [[CCC]], January 30, 2014
* [http://www.talkchess.com/forum/viewtopic.php?p=570955 Threads factor: Komodo, Houdini, Stockfish and Zappa] by [[Andreas Strangmüller]], [[CCC]], May 17, 2014 » [[Thread]], [[Komodo]], [[Houdini]], [[Stockfish]], [[Zappa]]
==2015 ...==
* [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]]
'''2016'''
* [http://www.talkchess.com/forum/viewtopic.php?t=59849 Houdini 5 in TCEC] by John Wentworth, [[CCC]], April 13, 2016 » [[TCEC Season 9]] <ref>[http://www.chessdom.com/houdini-5-to-participate-in-tcec-season-9/ Houdini 5 to participate in TCEC Season 9], [[Chessdom]], April 13, 2016</ref>
* [http://www.talkchess.com/forum/viewtopic.php?t=61357 Houdini 5 dev in TCEC] by [[Jouni Uski]], [[CCC]], September 08, 2016 » [[TCEC Season 9]]
* [http://www.talkchess.com/forum/viewtopic.php?t=61611 New Houdini] by [[Dann Corbit]], [[CCC]], October 05, 2016
* [http://www.talkchess.com/forum/viewtopic.php?t=62035 Houdini 5 has been released] by [[Robert Houdart]], [[CCC]], November 09, 2016
* [http://www.talkchess.com/forum/viewtopic.php?t=62366 chessbase houdini is out but...] by Stavros Atmatzidis, [[CCC]], December 03, 2016
'''2017'''
* [http://www.talkchess.com/forum/viewtopic.php?t=65211 Houdini 6 has been released] by [[Robert Houdart]], [[CCC]], September 18, 2017
* [http://www.talkchess.com/forum/viewtopic.php?t=65288 Scaling from FGRL results with top 3 engines] by [[Kai Laskos]], [[CCC]], September 26, 2017 » [[FGRL]], [[Komodo]], [[Stockfish]]
=External Links=
==Chess Engine==
* [https://en.wikipedia.org/wiki/Houdini_%28chess%29 Houdini (chess) from Wikipedia]
===Purchase===
* [http://www.cruxis.com/chess/houdini.htm Houdini Chess Engine]
* [https://shop.chessbase.com/en/products/houdini_6_pro_multiprocessor_version Houdini 6 Pro] [[ChessBase|ChessBase Shop]], September 17, 2017
* [https://shop.chessbase.com/en/products/houdini_5_pro_multiprocessor_version Houdini 5 Pro] [[ChessBase|ChessBase Shop]], December 02, 2016
* [https://shop.chessok.com/index.php?main_page=index&cPath=7_56 Houdini 6 and Aquarium 2018], [[ChessOK]] » [[Aquarium]]
===Interviews===
* [http://chess-king.com/images/kingintromaterials/HoudartInterview/InterviewHoudiniA.pdf Interview of Robert Houdart, the Creator of the Strongest Chess Engine in the world: Houdini] (pdf), [http://chess-king.com/ chess-king.com]
* [https://en.chessbase.com/post/houdini-3-the-world-s-strongest-che-engine-in-the-fritz-interface Houdini 3 – the world's strongest chess engine in the Fritz interface - Interview with Robert Houdart, author of Houdini], [[ChessBase|ChessBase News]], October 29, 2012
* [http://www.chessdom.com/robert-houdart-on-houdini-5-dev-in-tcec/ Robert Houdart on Houdini 5 dev in TCEC], [[Chessdom]], August 25, 2016 » [[TCEC Season 9]]
* [http://www.chessdom.com/interview-with-robert-houdart-mark-lefler-and-gm-larry-kaufman/ Interview with Robert Houdart, Mark Lefler and GM Larry Kaufman] by [[Nelson Hernandez]], [[Chessdom]], November 23, 2017 » [[TCEC Season 10]]
* [http://www.chessdom.com/interview-with-robert-houdart-author-of-the-champion-engine-houdini/ Interview with Robert Houdart, author of the champion engine Houdini], [[Chessdom]], December 08, 2017
===Reports===
* [https://en.chessbase.com/post/neu-houdini-6 New: Houdini 6 | ChessBase], [[ChessBase|ChessBase News]], October 18, 2017
* [https://en.chessbase.com/post/houdini-3-the-new-king-of-the-block-part-one- Houdini 3: the new king of the block (part one)] by [[Albert Silver]], [[ChessBase|ChessBase News]], November 13, 2012
* [https://en.chessbase.com/post/houdini-3-analyzing-in-the-cloud-part-two- Houdini 3: Analyzing in the cloud (part two)] by [[Albert Silver]], [[ChessBase|ChessBase News]], November 17, 2012
* [https://en.chessbase.com/post/houdini-4-the-800-pound-gorilla-2 Houdini 4: the 800-pound gorilla], [[ChessBase|ChessBase News]], December 07, 2013
* [https://thetech.com/2014/01/15/chess-v133-n62 One chess champion per laptop] by [http://www.mit.edu/~roberto/ Roberto Perez-Franco], [[Massachusetts Institute of Technology|MIT's]] [https://en.wikipedia.org/wiki/The_Tech_%28newspaper%29 The Tech], January 15, 2014 » [[TCEC Season 5]]
* [http://www.chessdom.com/houdini-5-to-participate-in-tcec-season-9/ Houdini 5 to participate in TCEC Season 9], [[Chessdom]], April 13, 2016 » [[TCEC Season 9]]
* [https://en.chessbase.com/post/houdini5tacticalmode Houdini 5's Tactical Mode: Releasing the Kraken] by [[Albert Silver]], [[ChessBase|ChessBase News]], December 08, 2016
* [https://en.chessbase.com/post/fair-play-in-engine-match Fair play in engine chess], [[ChessBase|ChessBase News]], December 30, 2016 » [[Houdini#5|Houdini 5]], [[Komodo#10|Komodo 10]]
* [https://en.chessbase.com/post/tcec-superfinal-houdini-vs-komodo TCEC: Superfinal Houdini vs Komodo] by [[Stephan Oliver Platz]], [[ChessBase|ChessBase News]], November 23, 2017 » [[TCEC Season 10]]
* [http://www.chessdom.com/houdini-is-tcec-season-10-champion/ Houdini is TCEC Season 10 champion!], [[Chessdom]], December 07, 2017
* [https://en.chessbase.com/post/houdini-wins-the-tcec-superfinal Houdini wins TCEC Superfinal] by [[Stephan Oliver Platz]], [[ChessBase|ChessBase News]], December 13, 2017 » [[TCEC Season 10]]
===Rating Lists===
* [http://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Houdini&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 Houdini] in [[CCRL|CCRL 40/40]]
* [http://www.computerchess.org.uk/ccrl/4040/cgi/engine_details.cgi?match_length=30&each_game=1&print=Details&each_game=1&eng=Houdini%206%2064-bit%204CPU#Houdini_6_64-bit_4CPU Houdini 6 64-bit 4CPU] in [[CCRL|CCRL 40/40]]
==Harry Houdini==
* [https://en.wikipedia.org/wiki/Harry_Houdini Harry Houdini from Wikipedia]
* [https://www.thegreatharryhoudini.com/ Harry Houdini - The Life of Harry Houdini]
* [http://www.loc.gov/rr/rarebook/coll/122.html Harry Houdini Collection]
* [https://www.biography.com/people/harry-houdini-40056 Harry Houdini Biography - Facts, Birthday, Life Story - Biography.com]
=References=
<references />
'''[[Engines|Up one level]]'''
[[Category:UCI]]
[[Category:Commercial]]
[[Category:Legend]]
[[Category:Magic]]
