14 votes
Accepted

What previous results match/compare to Alireza Firouzja's 3000+ performance in the European Team Championships?

An unofficial list of the highest Tournament Performance Ratings (TPRs) on record in standard FIDE classical tournaments since 1970 is here: https://deletionpedia.org/en/...
Mobeus Zoom's user avatar
  • 2,279
8 votes
Accepted

How do you calculate your Tournament Performance Rating?

TPR calculators and expected rating change. http://englishchess.org.uk/Juniors/tournament-performance-calculator/ http://www.uschess.org/content/view/13146/836/ Basically Performance rating is the ...
Fred Knight's user avatar
  • 3,122
7 votes

How do you calculate your Tournament Performance Rating?

Section 1.48 of the FIDE Title Regulations effective from 1 July 2017 specifies how the performance rating is calculated. The average rating of the opponents is adjusted by a value determined by ...
joriki's user avatar
  • 170
6 votes

Quickly converting board to bitboard representation using python-chess library

To convert a single bitboard to a numpy array: def bitboard_to_array(bb: int) -> np.ndarray: s = 8 * np.arange(7, -1, -1, dtype=np.uint64) b = (bb >> s).astype(np.uint8) b = np....
Mateen Ulhaq's user avatar
  • 1,264
6 votes

Quickly converting board to bitboard representation using python-chess library

python-chess already has the built in utilities to handle conversions. Here is an example: import chess board = chess.Board('rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1') WP = board....
AndrewGrant's user avatar
6 votes

If a pawn promotes to a checking piece while also revealing a check, it is a double check?

Yes, a double check is when two pieces give check at the same time. It doesn't matter how you got to that position. As to whether there's an error on that wiki, it's probably best to try to ask its ...
itub's user avatar
  • 10.5k
5 votes
Accepted

How can I find my performance rating?

Under FIDE rules, the performance rating is calculated by taking the average of your opponent's ratings, and then adding a factor from a table based on performance. Let's say you played 5 games, ...
D M's user avatar
  • 18.8k
5 votes
Accepted

Detect pinned pieces code

A: Let's use bishop for our example. xrayBishopAttacks works if we have the following position: but it doesn't work if you have this: The f3 knight is not pinned because there is something else ...
SmallChess's user avatar
  • 22.5k
5 votes
Accepted

FIDE norm chance expectation calculation question

Given the new requirements, I tried to do a calculation. I couldn't find one on the internet suitable for this task, but this one suggests that for one game between a 2150 and a 2450 player, the ...
Glorfindel's user avatar
  • 24.8k
5 votes
Accepted

Faster bit-board implementation in Javascript

The real speed in bitboards is created by precomputing the bitboards for every instance. This means that you already have the attacked squares for a rook on d4 and every other piece on every square. ...
Mike Jones's user avatar
  • 5,169
5 votes
Accepted

Lc0 gets slower if weight file gets bigger

The bigger weights file corresponds to a larger Neural Network, which means more computation per node, but better evaluation per node.This is expected, and there is nothing that can make a bigger NN ...
Oscar Smith's user avatar
  • 1,098
5 votes
Accepted

How did I overperform in this rapid tournament?

There is a game theory of why 1st round NFL drafts don't perform as well as expected. The reasoning is that the player had an above average couple of games and returned to his average performance. ...
Mike Jones's user avatar
  • 5,169
4 votes

How did I overperform in this rapid tournament?

Yes, it was luck or you are stronger in longer time controls. No one can really say which is the case for you personally, considering you only played a few longer games. To find out you just have to ...
Inertial Ignorance's user avatar
4 votes
Accepted

C++ vs Java Engine move generation performance

Your code looks fine. We can't really give you the exact cause, but we can give you some hints. Q: How did you generate sliding pieces? Sliding piece generation is typically the slowest because we ...
SmallChess's user avatar
  • 22.5k
4 votes

Detect pinned pieces code

Answering my own question here. I've managed to increase the speed of the move generation code, by implementing the pinnedPices() routine. The C++ version runs Perft (start_pos, 6) under ~3.5 secs, ...
Fernando's user avatar
  • 425
4 votes

Chess Engine: Faster Move Generation

Move generation has been tested to death in modern chess engines, and the current consensus is that the following two approaches are optimal for sliding pieces: A lookup table indexed by PEXT of the ...
konsolas's user avatar
  • 3,176
3 votes

How can I find my performance rating?

Performance rating doesn't make sense for a single game, it only makes sense if you play a bunch of games (at least 4 or 5) in a chess event. For example, in a round robin tournament with 4 players, ...
LeibnizGW's user avatar
  • 1,149
3 votes
Accepted

How to make Lichess local analysis utilize more cpu and memory?

The menu for the analysis board has sliders for CPUs and memory (see screenshot below). Have you tried adjusting those? Maybe whether they actually work or not depends on which browser you are using. ...
itub's user avatar
  • 10.5k
3 votes
Accepted

Can playing too much chess affect your performance?

At least for some players, yes, although how many games, the type of games, and in what period of time, causes burn out, I would assume varies from player to player. I've been reading "Bent Larsen's ...
Herb's user avatar
  • 4,207
3 votes
Accepted

Meditation practice among the chess elite?

I found these sources for "meditation" among the past 2 worlds champions: Carlsen: https://www.youtube.com/watch?v=ELoJbv4bCHw Anand: https://badrirag.wordpress.com/category/viswanathan-anand/ Q : ...
David's user avatar
  • 348
3 votes

How did I overperform in this rapid tournament?

In wild games with opposite side castling, etc anything is possible. Chances to win for the underdog increase. With your attacking style you are more likely to see much above average (but also much ...
user1583209's user avatar
  • 20.8k
3 votes

If a pawn promotes to a checking piece while also revealing a check, it is a double check?

Yes, the case you mentioned would also qualify as a double check. But it also depends on what your definitions are. If the Perft result does consider that to not be a double check, it doesn't mean ...
Inertial Ignorance's user avatar
3 votes

What previous results match/compare to Alireza Firouzja's 3000+ performance in the European Team Championships?

In addition to the information in last reply, There are also Wesly So 3183 and Karen Grigoryan 3103. But the level of the tournaments are not as sophisticated as Caruana and Firouzja case.
Komorebi's user avatar
2 votes
Accepted

How can I speed up my check detection in Javascript?

It looks like your engine is using very simple for loop and arrays. Your code simply loop over again and again, possibly repeat each search iteration. That’s obviously not good. Chess engine can’t ...
SmallChess's user avatar
  • 22.5k
2 votes

What is the most efficient way to calculate attack squares in a chess engine?

It may help to keep a list of each piece and the squares it attacks for the position. Then when a move occurs, you can reduce the work calculating for the pieces that don't move. Non-moving kings, ...
D Krueger's user avatar
  • 121
2 votes

Meditation practice among the chess elite?

I don't know of any studies. A quick search turned up this article where Nakamura says I don't do anything special to prepare myself although I do occasionally meditate!
Cleveland's user avatar
  • 7,574
2 votes

How to automatically evaluate a player's performance in a game?

chess.com CAPS. Compare CAPS score from chess.com (requires subscription), to table found in a graphic on this: https://www.chess.com/article/view/better-than-ratings-chess-com-s-new-caps-system . ...
JWILD's user avatar
  • 21
2 votes

Validate Engine moves using Perft and divide

Just to answer my own question, the bug I had is better explained here: http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=234034&t=25096 My make/undo/perft code are correct, ...
Fernando's user avatar
  • 425
2 votes
Accepted

Validate Engine moves using Perft and divide

Q1 I wouldn't code up a new divide function because if you have a bug in your code, your new function will also be buggy. Why don't you use Stockfish? Do you know you can run perft on Stockfish? In ...
SmallChess's user avatar
  • 22.5k
2 votes

C++ vs Java Engine move generation performance

Disclaimer: I can't support my claims with numbers. I don't have your engine to profile. It is mostly gut feelings. It looks like a performance killer is a castling test. Testing for canCastle*S (it ...
user58697's user avatar
  • 1,577

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