Search found 42 matches
- Thu Feb 13, 2020 12:50 am
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: Hashtable packing (e.g. to optimize magic bitboards) is strongly NP-complete
- Replies: 0
- Views: 1762
Hashtable packing (e.g. to optimize magic bitboards) is strongly NP-complete
2010 Volker Annuss shared his densely packed overlapping magic bitboards . The method he described was a heuristic based on simulated annealing. I was wondering if there is a better algorithm to pack hashtables, maybe even an efficient algorithm to find an optimal packing. Probably unsurprisingly to...
- Mon Oct 07, 2019 3:09 pm
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: PGN standard, its improvement and standardization
- Replies: 55
- Views: 16834
- Mon Oct 07, 2019 9:16 am
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: PGN standard, its improvement and standardization
- Replies: 55
- Views: 16834
Re: PGN standard, its improvement and standardization
Hiding such a PV in a normal comment (within braces) hides these from the normal display mechanisms, and thusshould be considered a very bad practice. Unfortunately the PV often coincides with the following moves of the game, and many GUIs don't support having distinct variations for the same moves...
- Sun Apr 07, 2019 6:15 pm
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: 7-men Syzygy attempt
- Replies: 588
- Views: 194365
Re: 7-men Syzygy attempt
This was introduced to return the correct DTZ for mate-in-1 positions. Context:
http://talkchess.com/forum/viewtopic.ph ... 506#757506
https://github.com/syzygy1/Cfish/commit ... d91bec9088
https://github.com/syzygy1/Cfish/commit ... cbddb82be6
http://talkchess.com/forum/viewtopic.ph ... 506#757506
https://github.com/syzygy1/Cfish/commit ... d91bec9088
https://github.com/syzygy1/Cfish/commit ... cbddb82be6
- Fri Mar 29, 2019 10:14 am
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: 7 man syzygy tablebase probe Fathom
- Replies: 2
- Views: 1303
Re: 7 man syzygy tablebase probe Fathom
If that's the only commit, then no, this is definitely not enough. It's a start, though.
- Thu Mar 21, 2019 1:01 pm
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: No bishop magics with fixed shift 8
- Replies: 17
- Views: 7184
Re: No bishop magics with fixed shift 8
Sorry, I moved the file in the repository. It still exists under v1 in https://github.com/niklasf/magics. Yes, that's a nice observation. Initially I did not think it is important, because due to the "-c" in the exponent the excluded range is quite small (at least compared to the period). However it...
- Fri Mar 01, 2019 1:53 pm
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: Fun challenge for best cool code
- Replies: 8
- Views: 2680
Re: Fun challenge for best cool code
So, I think Python Chess now accepts both: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq x, y Yeah, on the master branch it now even defaults to w - - 0 1 respectively. Not sure if that's a bit too relaxed ... in any case a user could parse, r...
- Wed Dec 12, 2018 7:02 pm
- Forum: Computer Chess Club: General Topics
- Topic: lila-tablebase: Syzygy tablebase server
- Replies: 2
- Views: 1187
lila-tablebase: Syzygy tablebase server
https://github.com/niklasf/lila-tablebase: This is a Syzygy tablebase server that I created as a backend for https://syzygy-tables.info and https://lichess.org/analysis#explorer. It is intended for remote access to tablebases. (Obviously not for low latency access in engines). For the last 3 months ...
- Tue Aug 14, 2018 10:59 pm
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: 7-men Syzygy attempt
- Replies: 588
- Views: 194365
Re: 7-men Syzygy attempt
Congrats for finishing all tables with <= 1 pawns! Getting close to completion now. Based on the tablebase.lichess.ovh mirror: pawns generated/total - 396/396 P 330/330 PP 166/180 PPP 55/72 PPPP 14/20 PPPPP 2/3 eg generated/total 6v1 126/126 5v2 350/350 4v3 487/525 Small plug: I've been updating syz...
- Thu Jun 28, 2018 1:29 pm
- Forum: Computer Chess Club: Programming and Technical Discussions
- Topic: 7-men Syzygy attempt
- Replies: 588
- Views: 194365
Re: 7-men Syzygy attempt
The current probing code seems to try and read past the end of the table file when probing the DTZ for 2B5/1R6/k7/8/8/P7/6B1/q6K w - - 0 1 (KRBBPvKQ). Can reproduce in python-chess as well. Here's a gdb session with Cfish: Starting program: /root/Cfish/src/cfish [Thread debugging using libthread_db ...