TalkChess.com

Ferdy wrote: ↑Wed Jul 31, 2019 5:55 am

noobpwnftw wrote: ↑Wed Jul 31, 2019 5:10 am finally there exists a "Discover" program people can run, which loads any UCI-compatible engine and play games, contributing moves encountered during the process.

I tried to compile ChessDBDiscover and it seems to work. Created an engine dir and put engine.exe, a renamed stockfish dev engine, then run ChessDBDiscover.exe with default config values.



So what does the ChessDBDiscover.exe is doing? Does it play engine vs engine matches based on StartFEN in config file? If so how many games? Does it send the results to the cloud?

noobpwnftw wrote: ↑Sat Jul 27, 2019 11:54 pm For those who want to probe my database locally or for other unspecified reasons, here is a full database snapshot of my book project as of today:

ftp://ftp.chessdb.cn/pub/chessdb/data-s ... 190728.tar

The database contains about 3 billion unique chess positions, mostly connected to startpos, analyzed by Stockfish with no less than 22 plies at terminal node and has a very wide multi-pv exploration, the scores been back-propagated using a weighted averaging function, also for most of the positions there is a special field(encoded as 'a0a0') marking known shortest distance of the position from startpos.

Using this database snapshot is as simple as putting the data files under your database folder and launch the server, yet still, I'd recommend you to use the online API and make feature requests if you need any, since it is getting updated constantly and I have no plans to make such kind of snapshots very frequently(while waiting for a contributor to make incremental snapshots possible).

This database snapshot is released into the public domain.

noobpwnftw wrote: ↑Wed Jul 31, 2019 9:48 am

Ferdy wrote: ↑Wed Jul 31, 2019 5:55 am

noobpwnftw wrote: ↑Wed Jul 31, 2019 5:10 am finally there exists a "Discover" program people can run, which loads any UCI-compatible engine and play games, contributing moves encountered during the process.

I tried to compile ChessDBDiscover and it seems to work. Created an engine dir and put engine.exe, a renamed stockfish dev engine, then run ChessDBDiscover.exe with default config values.



So what does the ChessDBDiscover.exe is doing? Does it play engine vs engine matches based on StartFEN in config file? If so how many games? Does it send the results to the cloud?

Yes, it keeps playing games and submitting results until you close the program.

Ferdy wrote: ↑Wed Jul 31, 2019 2:50 pm How do I know if positions from the run are saved in cloud?

Ferdy wrote: ↑Tue Jul 30, 2019 10:40 am

Ovyron wrote: ↑Tue Jul 30, 2019 12:54 am

Ferdy wrote: ↑Tue Jul 30, 2019 12:47 amUse fen and not epd.
If you only have epd, just add "0 1" at the end to make it a fen.

Thanks, now it works.

This is really cool, I kind of feel like I downloaded some huge database that weighs just 9MB

Also working on simple html interface, I hope to release it next week.

Ferdy wrote: ↑Fri Aug 02, 2019 1:26 pm
Html interface is released at https://github.com/fsmosca/ChessDB-Online-Book

Download the whole thing and open index.html.

Or try it at https://fsmosca.github.io/ChessDB-Online-Book/
Make sure to enable javascript.

zullil wrote: ↑Fri Aug 02, 2019 3:10 pm How was the "winrate" for each position determined?

// 2019-08-02: ChessDB does not return winrate when score is mate.
// So we will calculate winrate by logistic function
if (typeof winrate === "undefined") {
  const K = 1.2;
  winrate = 100 * 1/(1 + (10**(-K*score/400)));
  winrate = winrate.toFixed(2);
}