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Fruit (chess)
Fruit is a chess engine developed by Fabien Letouzey. In the SSDF rating list released on November 24, 2006, Fruit version 2.2.1 had a rating of 2842. In the CEGT rating list released on January 24, 2007, Fruit version 2.2.1 had a rating of 2776. History At the World Computer Chess Championship in Reykjavík in 2005, Fruit 2.2 scored 8.5 out of 11, finishing in second place behind Zappa. Until Version 2.1 (''Peach''), Fruit was free and open-source software subject to the requirements of the GNU General Public License and as such contributed much to the development in computer chess in recent years. Some people still work on the v2.1 source code and have created variations from the original Fruit. As of July 23, 2007, Fruit became freeware. Fruit 2.3.1 was one of the top 3 free UCI chess engines. Technical details of Fruit 2.1 Fruit uses the classical Negascout ( principal variation search) algorithm with iterative deepening to traverse the game tree. It also uses the nul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fabien Letouzey
Fabien is both a French given masculine name and a French surname. Notable people with the name include: People with the given name Fabien: * Fabien Audard (born 1978), French professional football (soccer) player * Fabien Barthez (born 1971), retired French football goalkeeper * Fabien Boudarène (born 1978), French footballer * Fabien Camus (born 1985), French football player * Fabien Chéreau (born 1980), French computer programmer * Fabien Cool (born 1972), former French football goalkeeper * Fabien Cordeau (1923-2007), politician in Quebec, Canada * Fabien Cousteau (born 1967), French aquatic filmmaker * Fabien Delrue (born 2000), French badminton player * Fabien Foret (born 1973), professional motorcycle racer * Fabien Frankel (born 1994), British actor * Fabien Galthié (born 1969), French rugby union coach and former player * Fabien Gilot (born 1984), French Olympic and world champion swimmer * Fabien Giroix (born 1960), French racing driver * Fabien Laurenti (b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Principal Variation
A variation can refer to a specific sequence of successive moves in a turn-based game, often used to specify a hypothetical future state of a game that is being played. Although the term is most commonly used in the context of Chess analysis, it has been applied to other games. It also is a useful term used when describing computer tree-search algorithms (for example minimax) for playing games such as Go{{cite web , url=http://www.andromeda.com/people/ddyer/go/search.html, title=Searches, tree pruning and tree ordering in Go, date=21 December 2007 or Chess. A variation can be any number of steps as long as each step would be legal if it were to be played. It is often as far ahead as a human or computer can calculate; or however long is necessary to reach a particular position of interest. It may also lead to a terminal state in the game, in which case the term "winning variation" or "losing variation" is sometimes used. Principal variation The principal variation refers to the par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmetric Multiprocessing
Symmetric multiprocessing or shared-memory multiprocessing (SMP) involves a multiprocessor computer hardware and software architecture where two or more identical processors are connected to a single, shared main memory, have full access to all input and output devices, and are controlled by a single operating system instance that treats all processors equally, reserving none for special purposes. Most multiprocessor systems today use an SMP architecture. In the case of multi-core processors, the SMP architecture applies to the cores, treating them as separate processors. Professor John D. Kubiatowicz considers traditionally SMP systems to contain processors without caches. Culler and Pal-Singh in their 1998 book "Parallel Computer Architecture: A Hardware/Software Approach" mention: "The term SMP is widely used but causes a bit of confusion. ..The more precise description of what is intended by SMP is a shared memory multiprocessor where the cost of accessing a memory location ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rybka
Rybka is a computer chess engine designed by International Master Vasik Rajlich. Around 2011, Rybka was one of the top-rated engines on chess engine rating lists and won many computer chess tournaments. After Rybka won four consecutive World Computer Chess Championships from 2007 to 2010, it was stripped of these titles after the International Computer Games Association concluded in June 2011 that Rybka was plagiarized from both the Crafty and the Fruit chess engines and so failed to meet their originality requirements. In 2015FIDE Ethics Commission following a complaint put forward by Vasik Rajlich and chess engine developer and games publisher Chris Whittington regarding ethical breaches during internal disciplinary proceedings, ruled the ICGA guilty and sanctioned ICGA with a warning. Case 2/2012. ChessBase published a challenging two-part interview-article about the process and verdict with ICGA spokesperson David Levy. Subsequently, ChessBase has published Rybka to prod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crafty
Crafty is a chess program written by UAB professor Dr. Robert Hyatt, with continual development and assistance from Michael Byrne, Tracy Riegle, and Peter Skinner. It is directly derived from Cray Blitz, winner of the 1983 and 1986 World Computer Chess Championships. Tord Romstad, the author of Stockfish, described Crafty as "arguably the most important and influential chess program ever". Crafty finished in second place in the 2010 Fifth Annual ACCA Americas' Computer Chess Championships. Crafty lost only one game, namely to the first-place winner, Thinker. Crafty also finished in second place in the 2010 World Computer Rapid Chess Championships. Crafty won seven out of nine games, finishing just behind the first-place winner Rybka by only ½ point. In the World Computer Chess Championships 2004, running on slightly faster hardware than all other programs, Crafty took fourth place with the same number of points as the third-place finisher, Fritz 8. On the November 2007 S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Chess
GNU Chess is a free software chess engine and command-line interface chessboard. The goal of GNU Chess is to serve as a basis for research, and as such it has been used in numerous contexts. GNU Chess is free software, licensed under the terms of the GNU General Public License version 3 or any later version, and is maintained by collaborating developers. As one of the earliest computer chess programs with full source code available, it is one of the oldest for Unix-based systems and has since been ported to many other platforms. Features As of 2 September 2017 GNU Chess 5.60 is rated at 2813 Elo points (when using one CPU) on CCRL's 40-moves-in-40-minutes list. For comparison, the strongest chess engine in the list using one CPU, Strelka 5.5, has an Elo rating of 3108 (the 295 ELO point difference indicates that Strelka 5.5 would beat GNU Chess 5.60 in about 85% of games). On the same list, Fritz 8 is rated at only 2701, and that program in the 2004 Man vs Machine World ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Cluster
A computer cluster is a set of computers that work together so that they can be viewed as a single system. Unlike grid computers, computer clusters have each node set to perform the same task, controlled and scheduled by software. The components of a cluster are usually connected to each other through fast local area networks, with each node (computer used as a server) running its own instance of an operating system. In most circumstances, all of the nodes use the same hardware and the same operating system, although in some setups (e.g. using Open Source Cluster Application Resources (OSCAR)), different operating systems can be used on each computer, or different hardware. Clusters are usually deployed to improve performance and availability over that of a single computer, while typically being much more cost-effective than single computers of comparable speed or availability. Computer clusters emerged as a result of convergence of a number of computing trends including t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open-source Software
Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Open-source software may be developed in a collaborative public manner. Open-source software is a prominent example of open collaboration, meaning any capable user is able to participate online in development, making the number of possible contributors indefinite. The ability to examine the code facilitates public trust in the software. Open-source software development can bring in diverse perspectives beyond those of a single company. A 2008 report by the Standish Group stated that adoption of open-source software models has resulted in savings of about $60 billion per year for consumers. Open source code can be used for studying and allows capable end users to adapt software to their personal needs in a similar way user scripts an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
End-of-life (product)
An end-of-life product (EOL product) is a product at the end of the product lifecycle which prevents users from receiving updates, indicating that the product is at the end of its useful life (from the vendor's point of view). At this stage, a vendor stops the marketing, selling, or provisioning of parts, services, or software updates for the product. The vendor may simply intend to limit or end support for the product. In the specific case of product sales, a vendor may employ the more specific term "end-of-sale" ("EOS"). All users can continue to access discontinued products, but cannot receive security updates and technical support. The time-frame after the last production date depends on the product and relates to the expected product lifetime from a customer's point of view. Different lifetime examples include toys from fast food chains (weeks or months), mobile phones (3 years) and cars (10 years). Product support Product support during EOL varies by product. For hardware ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Board Representation (chess)
Board representation in computer chess is a data structure in a chess program representing the position on the chessboard and associated game state. Board representation is fundamental to all aspects of a chess program including move generation, the evaluation function, and making and unmaking moves (i.e. search) as well as maintaining the state of the game during play. Several different board representations exist. Chess programs often utilize more than one board representation at different times, for efficiency. Execution efficiency and memory footprint are the primary factors in choosing a board representation; secondary considerations are effort required to code, test and debug the application. Early programs used piece lists and square lists, both array based. Most modern implementations use a more elaborate but more efficient bit array approach called ''bitboards'' which map bits of a 64-bit word or double word to squares of the board. Board state A full description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evaluation Function
An evaluation function, also known as a heuristic evaluation function or static evaluation function, is a function used by game-playing computer programs to estimate the value or goodness of a position (usually at a leaf or terminal node) in a game tree. Most of the time, the value is either a real number or a quantized integer, often in ''n''ths of the value of a playing piece such as a stone in go or a pawn in chess, where ''n'' may be tenths, hundredths or other convenient fraction, but sometimes, the value is an array of three values in the unit interval, representing the win, draw, and loss percentages of the position. There do not exist analytical or theoretical models for evaluation functions for unsolved games, nor are such functions entirely ad-hoc. The composition of evaluation functions is determined empirically by inserting a candidate function into an automaton and evaluating its subsequent performance. A significant body of evidence now exists for several games l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Null-move Heuristic
In computer chess programs, the null-move heuristic is a heuristic (computer science), heuristic technique used to enhance the speed of the alpha-beta pruning search algorithm, algorithm. Rationale Alpha-beta pruning speeds the minimax algorithm by identifying ''cutoffs'', points in the game tree where the current position is so good for the side to move that best play by the other side would have avoided it. Since such positions could not have resulted from best play, they and all branches of the game tree stemming from them can be ignored. The faster the program produces cutoffs, the faster the search runs. The null-move heuristic is designed to guess cutoffs with less effort than would otherwise be required, whilst retaining a reasonable level of accuracy. The null-move heuristic is based on the fact that most reasonable chess moves improve the position for the side that played them. So, if the player whose turn it is to move can forfeit the right to move (or make a null mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
