Search found 2085 matches

by Michel
Sat Feb 22, 2020 12:56 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: EPD destruction tests
Replies: 81
Views: 8610

Re: EPD destruction tests

First two are NOT correct. White or black can never have more that 16 pieces counting king. Not 17 or 18. The rules of chess say 16 pieces. 8 pawns, two rooks, bishops and knights, queen and king. The pawns can promote into 8 pieces excluding kings So 16 is it unless you are doing non-chess. For th...
by Michel
Mon Feb 17, 2020 7:55 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: hash collisions
Replies: 370
Views: 54656

Re: hash collisions

This whole discussion is silly. About the only hard requirement of a chess program is that it plays legal moves when given a legal position. So a "bug" in a chess program is mostly an undefined concept. A pv must be sensible? Some people here will argue that a pv is only "cosmetics"... Endgame troll...
by Michel
Mon Feb 03, 2020 11:04 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Stockfish Reverts 5 Recent Patches
Replies: 9
Views: 3374

Re: Stockfish Reverts 5 Recent Patches

Michel wrote:
Sun Feb 02, 2020 10:28 pm
I wrote a simple multi-threaded C version of the pentanomial simulator.

https://github.com/vdbergh/simul

Everything in a single C file. As it is much much faster than the Python version one can see better how accurate the implementation is.
Now with a decent README.md!
by Michel
Sun Feb 02, 2020 10:28 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Stockfish Reverts 5 Recent Patches
Replies: 9
Views: 3374

Re: Stockfish Reverts 5 Recent Patches

I wrote a simple multi-threaded C version of the pentanomial simulator.

https://github.com/vdbergh/simul

Everything in a single C file. As it is much much faster than the Python version one can see better how accurate the implementation is.
by Michel
Sun Feb 02, 2020 9:53 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Stockfish Reverts 5 Recent Patches
Replies: 9
Views: 3374

Re: Stockfish Reverts 5 Recent Patches

The validity of the pentanomial model can be verified by simulation. https://github.com/vdbergh/pentanomial Concerning short tests: there are various things to consider, notably: Fishtest Elo bounds are no longer BayesElo. The stopping time distribution for an SPRT has long tails. The great majorit...
by Michel
Thu Jan 23, 2020 7:13 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Hyatt 4000 openings
Replies: 7
Views: 1929

Re: Hyatt 4000 openings

Unbalanced opening are completely safe to use as long as the pentanomial variance is used to calculate the error bars. For SPRT it is bit more complicated but pentanomial SPRT has been integrated into Fishtest recently and is working satisfactorily. So now one can just copy that code (although it is...
by Michel
Mon Jan 20, 2020 4:10 pm
Forum: Computer Chess Club: General Topics
Topic: Dumping a search tree
Replies: 1
Views: 553

Re: Dumping a search tree

GnuCheese can do it... http://hardy.uhasselt.be/GnuCheese/ $ gnucheese Initializing 64 bit magics... Transposition table: Entries=2048K Size=49152K Pawn hash table: Entries=1K Size=72K Eval cache table: Entries=1024K Size=8192K 3-pc GTBs complete No 4-pc GTBs available No 5-pc GTBs available GnuChee...
by Michel
Thu Jan 16, 2020 7:45 am
Forum: Computer Chess Club: General Topics
Topic: Women World Fischer Random Championship 2019 Next Month in USA
Replies: 81
Views: 8702

Re: Women World Fischer Random Championship 2019 Next Month in USA

That's not what you are claiming. You have repeatedly gotten wrong what I'm claiming. Now I'm going to claim that you're the only person in the world that considers a King on c1 castling with a rook on h1 a legal chess move. If anybody reading this agrees with you and replies to this message saying...
by Michel
Fri Jan 10, 2020 7:51 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: RMO - Randomized Move Order - yet another Lazy SMP derivate
Replies: 114
Views: 24092

Re: RMO - Randomized Move Order - yet another Lazy SMP derivate

The above Dr. Dobbs journal article references this paper: https://www.researchgate.net/publication/221583842_Superlinear_Speedup_in_Parallel_State-Space_Search When N processors perform depth-first search on disjoint parts of a state space tree to find a solution, the speedup can be superlinear (i...
by Michel
Tue Jan 07, 2020 11:23 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: RMO - Randomized Move Order - yet another Lazy SMP derivate
Replies: 114
Views: 24092

Re: RMO - Randomized Move Order - yet another Lazy SMP derivate

It is only the fixed depth tests that I prefer v4, but there is no reason not to stop the search if one thread reaches the depth limit. It turns out Stockfish can be made stronger by simply repeating a single-threaded search at a given depth a number of times. In fact, it seems a single-threaded se...