Questions tagged [engines]
Questions relating to chess engines: any computer program that is able to play/analyze chess positions.
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What algorithm is used when an engine is branded by a certain player?
I've seen a "play Kasparov" on flights, and during those recent chess tournaments, they had a "Play Magnus at 13 (or some young age)" segment where some players in the tournament ...
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My engine's alpha-beta search returns negative score eval. on odd depths and positive on even. Dont understand what is causing this bug
I've been working on implementing/improving my engine's search function the past few days, but yesterday I decided my current search implementation was a mess and that it would be much better to ...
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Will writing a chess engine help my chess?
At first the premise seems absurd - the computer engine relies much more on brute-force search (Shannon's Type A Strategy) over selecting a few strong lines with heuristics (Type B Strategy). But can ...
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What free programs do exist to comment chess games? For Windows, Linux, and Mac
What free programs do exist to comment chess games? For Windows, Linux, and Mac.
I know that ChessBase and ChessOK Aquarium can do it. However, it is my understanding that they are not free.
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Stack data structure to store chess positions?
One method I thought of for storing chess positions is a stack. This is because when you go one move deeper in the search, you add that position onto the stack, and delete the node when finish, this ...
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Why do I get two different ratings for same position (López Opening: Morphy Defense, Caro Variatio) on chess.com?
I've been trying to get back into chess a bit, and noticed the option to practice certain positions - but I've been puzzled by the rating when playing a "Friendly" game (which gives you ...
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How are nodes per second in engines controlled?
I am trying to experiment with the parameter -n in Phalanx XXV. I play a match between phalanx0 (phalanx without any options) vs phalanx1 (phalanx -n 512000 -t 131072). Both phalanx0 and phalanx1 are ...
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Is there a Correspondence Chess ranking on Lichess.org on 2022?
A similar question was posted in the past (2020):
Is there a way on lichess to see the Correspondence chess rankings?
However, that solution is not working anymore. In my perspective, things have ...
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How does centipawn scoring work?/Why is a higher (positive) score horrible while a lower score is better?
I'm a total beginner in Chess. I've known the basic rules for at least 20 years, but have never played it somewhat serious. Only toddler-level.
I recently started trying to learn how to play properly. ...
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Is it possible to only generate one color's legal moves?
Let's say I have a position where white is to move, and I need white's legal moves. Is there any way where it is not necessary to generate black's legal moves? You only need black's moves for white's ...
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Are there chess programs that have a notion of a chaotic or volatile position?
I would like to know what are some quantitative criteria to characterize chaotic or volatile positions, and if there are engines or other programs that implement such criteria. One application I have ...
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How to implement programming with board states (turn, en passant squares, castling rights)
From Gigantua, the fastest chess move generator, it says that
The same holds true for the castling squares and most importantly the current moving color becomes a compiletime template and not an if ...
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Why do Engines show a fraction for the "Depth" and "Current Node" values?
Forgive me if this has been asked elsewhere, but I've both Googled and searched here at CSE and cannot find an answer.
When I'm using an Engine for analysis (in this case, Stockfish 15), I've noticed ...
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Legal chess move generator architecture
I am building a chess engine and I want the engine to directly generate legal moves (instead of pseudo legal + validation).
For this, I am keeping in the chess board structure a bitboard of all ...
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How would the min max algorithm of a chess engine work in the case of 3 player chess?
I understand that for 2 player chess if an engine is playing white, then the engine uses a min max algorithm, which assumes that black will always make the move that is best for black, or worst for ...
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Uniformly generate random chess positions
I want to generate a random legal standard chess position. By legal I mean a chess position that can be reached from the starting position in some amount of moves. My problem is that I want this ...
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Tool for storing multiple engines analysis of chess positions databse
I am looking for a tool that can store engine analysis of a chess positions database. It should be able to store multiple lines of analysis with complete info like depth, tablebase hits, score, etc.; ...
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Border pieces in Magic Bitboards
I've been trying to understand magic bitboards, but everywhere I've read failed to explain how edge pieces are handled.
The pieces at the borders are ignored to save space.
So for a bishop at D3, the ...
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Can't properly use python stockfish package in Mac
I'm trying to get stockfish for python working but I am running into issues. This is my code so far.
from stockfish import Stockfish
stockfish = Stockfish('/Users/Me/opt/anaconda3/lib/python3.9/site-...
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How do I set up an engine never to resign in Arena GUI?
Is there a way to set up the engine in a way it never resignes?
I want to practice mating with bishop and knight but after the engine reaches the depth it can tell it will be checkmated it resigns. I ...
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Which GM said something along the lines of "I can beat any chess engine; just give me time enough (to prevent blunders)"
So I guess I read this long time ago -most probably in the 2000s, when engines started to beat humans. I just have no idea who said it, but I guess it was not a top player at that moment (say Kasparov ...
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Scid vs. PC: a hint needed
I have now installed Scid vs. PC and I have made my first move with White to e4. Now the engine computes the position tree. How can I stop it and make it move with black after some fixed time ?
It ...
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How to find 'Thermopylaes' with engines?
Motivation
“You must take your opponent into a deep dark forest where 2+2=5, and the path leading out is only wide enough for one." – Michail Tal
I am looking for ways to systematically find ...
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Is testing an opening by having a computer play against itself viable?
Recently, I got into a brief argument with a colleague when I mentioned that I wanted to use an engine playing against itself to generate a larger sample size for a rare sideline.
His argument was ...
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How do you set up two engines to play each other on a cloud server?
I am exploring a semi-novel idea in the London system, where I play 2...b5!? after 1. d4 Nf6 2. Bf4
A main line goes 3.Nf3 Bb7 4.e3 and now:
4...a6 5.Bd3 e6 or Nh5
4...a6 5.c4 bxc4/b4
4...b4 5.Bd3 e6/...
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Is it worth it to use a redundant mailbox representation in addition to bitboards?
Just like the title says. A mailbox would allow for better handling of checking "which piece is at a certain square," and I see no real downsides to it besides the need to synchronize it ...
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Why isn't legal move filtering done at search time?
Most engines have some method of filtering out pseudo-legal moves from the actual legal ones. However, is there any reason not to keep them? With bit-boards, you can quickly filter out the ones that ...
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How do Chess Bitboards generate individual moves?
If I have a pawn bitboard like this, for example,
00000000
00000000
00000000
00000000
00001000
00000001
11110110
00000000
generating all of the, say, legal capture moves to the right will perform a ...
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How do you nerf Stockfish to analyze the same position multiple times?
I want to make some statistics by analyzing the same position, multiple times, at different levels of Stockfish.
Precisely, I would like Stockfish to analyze a specific position at different "...
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What does it mean when stockfish evaluates a move as an inaccuracy after previously thinking it was the best move?
I stumbled onto this position from a game posted on reddit. Stockfish gives the best move as cxd4, which it evaluates as +2.
If you play cxd4, it then says cxd4 was an inaccuracy (only being +1), and ...
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Why does Stockfish miss mate in 5 with only two legal moves?
I'm interested to understand what is going on for Stockfish on Lichess here. There are only two legal moves for Black, and it gives the position mate-in-14 for white.
When asked to play its ...
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If you play an engine in Arena, how do you send it setoption commands?
I really want to play two engines against each other, one with a tablebase path and one without, but I assume this is just a special case of the question in the title.
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Why does f3 weaken white's position here?
Take this game:
[fen ""]
[Startply "13"]
1. d4 d5 2. Bf4 Nc6 3. Nf3 Bf5 4. e3 Nb4 5. Nh4?? Bxc2 6. Qd2 e5 7. Bg3 Be4 (7... Bxb1 8. Rxb1) 8. f3 Bxb1 9. Rxb1
I'm specifically ...
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Are engines impaired by the 50-move rule?
Are we missing too much from the 50-move rule implementation to engines, whether HCE (Hand-crafted evaluation) or/and NN (Neural Network)?
We know that certain endgames are a win without the rule.
...
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Testing Mate Possibility Without Use of King
I would like to be able to convince myself of the possibility (or lack thereof) of mate using various piece combinations in which the attacker doesn't use their own king.
I'd like to approach this by ...
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Help with evaluating this position
rn2k2r/ppp2p2/4bn1p/2bp4/8/1B3N1P/PPP2PP1/RNB1R1K1 w Qkq - 0 1
I am having trouble evaluating this position, I believe the activity of the pieces is equal, besides the week h6 pawn I cannot see why ...
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Issue with connecting engine to lichess bot (uci communication)
My engine is responding correctly to the first inputs from the GUI (as above), but when it receives go movetime 10000 it just crashes and I don't know why. When I test my engine manually in CMD I get ...
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The ultimate decision of the eternal bishop vs knight question
The following is...disturbing.
[FEN "bbbbkbbb/bbbbbbbb/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
Black is about 15*3-38, say 10 units up (as Black will also grab a pawn and exchange on b2 or ...
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Why do these convergent lines evaluate differently?
I recently analyzed alternative lines for this puzzle on chess.com.
[Event "French Championship"]
[Site "Val d'Isere FRA"]
[Date "2002.08.23"]
[Round "5"]
[...
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Why is my chess engine that uses minimax with alpha-beta pruning so slow, even at depth 3?
I have little experience with any sort of chess AI and am at a complete loss as to why it still takes a couple of seconds to calculate a decent move even at just depth 3. Here is the code:
private ...
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Lichess Cloud Evaluation Flaw?
In the following position that's in the Traxler Counterattack: https://lichess.org/analysis/r1b1k2N/ppp1q1pp/5n2/3Pp3/2Bn4/8/PPPP1bPP/RNBQ1K1R_w_q_-_1_9
[fen "r1b1k2N/ppp1q1pp/5n2/3Pp3/2Bn4/8/...
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Hamppe-Meitner, the final verdict?
[FEN ""]
1.e4 e5 2.Nc3 Bc5 3.Na4 Bxf2+
For those of you who never heard of Hamppe-Meitner. Now I dimly remember that a super engine somewhere found a White win, but even the bringer of the ...
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Do engines have a larger advantage over a human at long or short time controls?
Question: Title question, basically: do engines have a larger advantage over a human at long or short time controls? Have any studies been done on this?
Context for the question: On a reddit thread ...
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Optimising Stockfish parameters when batch-analyzing with python-chess
I am running a python script that analyzes a large batch of PGN games (each of ~5,000 games) across and exports the games evaluations. It calls Stockfish 14 to analyze each game at depth 20. **[EDIT: ...
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What's the strongest non-ML chess engine?
What's the current strongest Chess Engine built solely on heuristics, no neural networks or any kind of deep learning?
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Do modern chess engines learn material values through self-play?
I have a simple question about how Chess engines like Stockfish and Leela value material. Do they use traditional material values (i.e. 1 for pawn, 3 for knight/bishop, 5 for rook, 9 for queen), or do ...
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Looking for free versions of older chess engines
In connection with another project, I am looking on the internet for some free versions of older chess engines, such as some of the old Chessmaster engines from the 1990s. I would even take an old ...
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Python Efficient Board Scoring Function To Use As Placeholder
I'm building a chess engine in Python. I'd like to find a board evaluation function that would be easy to put into my engine as a placeholder while I work on other aspects of the engine first.
I would ...
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Using pgn-extract to output FEN + evaluation
I'm using pgn-extract to convert a PGN database into FEN + evaluations. My goal is something like this:
1. e4 e6 2. d4 b6 3. a3 Bb7
Into this:
rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 ...
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Approximating a rating for too strong engines
Suppose we have an extremely strong engine that happens to win every game it participates in even against the most powerful engines and players.
If it continues to win every game, its rating (for ...
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