Search found 151 matches

by elpapa
Fri Jun 07, 2019 7:04 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Hash collision?
Replies: 42
Views: 1462

Re: Hash collision?

chrisw wrote:
Fri Jun 07, 2019 2:43 pm
Puzzle. Suppose a search takes X nodes and the hashtable is 2^n in size. You would like to be 95% confident no two nodes have a hash collision.

What’s the formula connecting X and n?
This will occupy my mind for days and in the end I won't be able to solve it, thank you very much.
by elpapa
Fri Jun 07, 2019 6:37 pm
Forum: Computer Chess Club: General Topics
Topic: Mortimer trap test bug in Stockfish 10
Replies: 23
Views: 741

Re: Mortimer trap test bug in Stockfish 10

Jp Coming close to the hot point. When you continue 6.Nc4 (which is inferior line according to Stockfish) after 10 moves , Stockfish evaluates -3.54 for black. But when you continue 6.Nxf7 (Stockfish’s best choice for white ), then 10 moves afterward, Stockfish evaluates -4.57 for black ! Is this l...
by elpapa
Fri Jun 07, 2019 3:32 pm
Forum: Computer Chess Club: General Topics
Topic: Mortimer trap test bug in Stockfish 10
Replies: 23
Views: 741

Re: Mortimer trap test bug in Stockfish 10

As you may know Mortimer trap is a famous trap in Ruy lupez openining .(google it and you’ll find it easily). Also it’s a valid test for new chess engines! According to all chess literature and famous GMs the best continuation in move 6 for white is 6.Nc4 ?! But when you test the position by Stockf...
by elpapa
Fri Jun 07, 2019 3:01 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: correct way to score promotions using MVV-LVA
Replies: 6
Views: 339

Re: correct way to score promotions using MVV-LVA

Including underpromotion to knight? Yes, it's not worth the effort in QS. In main search however, underpromotions should be searched. Even in main search you can omit under-promotions to bishop, at least I've never seen a game where under-promotion to bishop led to anything useful. It happens once ...
by elpapa
Tue May 07, 2019 3:28 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Time reduction adding a/b to mini/max?
Replies: 9
Views: 637

Re: Time reduction adding a/b to mini/max?

Robert Pope wrote:
Mon May 06, 2019 4:17 pm
Isn't the average branching factor for AB with random sorting = sqrt(N) (ignoring odd/even effects). So AB at 6 ply would be somewhere on the order of 6^6 ~ 50K nodes.
That's with perfect move ordering, IIRC.
by elpapa
Mon May 06, 2019 4:47 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: A bug is squashing me. HELP!
Replies: 20
Views: 1555

Re: A bug is squashing me. HELP!

So far all I have is a material searcher. From the initial position it returns a score of either 100 or -100 depending upon the modification or search depth. Well, that should be impossible if you only search a few ply, although I'm not sure what you mean by modification. If I were you I would add ...
by elpapa
Sun May 05, 2019 11:55 am
Forum: Computer Chess Club: General Topics
Topic: Bluefish vs Leela in TCEC , who will win? BF =170 Threads, Lc0 =2x GPU
Replies: 40
Views: 3153

Re: Bluefish vs Leela in TCEC , who will win? BF =170 Threads, Lc0 =2x GPU

Someone builds some sort of super train being able to cover L.A to NYC in 10 hours. Everyone is cheering.

As it turns out, it reaches Philadelphia in 5 hours and stands still there for 4½ hours before finishing the journey. Now everyone is booing.

Oh, the stupid masses.
by elpapa
Sun Jan 06, 2019 5:12 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Writing bugs
Replies: 66
Views: 7816

Re: Writing bugs

x <= MAX_MOVES
x < MAX_MOVES
by elpapa
Thu Nov 15, 2018 2:00 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Puzzle Position #1
Replies: 16
Views: 1287

Re: Puzzle Position #1

The bishop on a4 is wrong, it should be a pawn. Kholmov played 18. axb5.

https://www.365chess.com/view_game.php?g=2685254&m=1
by elpapa
Tue Sep 18, 2018 8:55 pm
Forum: Computer Chess Club: General Topics
Topic: Who would be the greatest Chess960 Champion ever?
Replies: 13
Views: 2401

Re: Who would be the greatest Chess960 Champion ever?

Chessqueen wrote:
Tue Sep 18, 2018 8:05 pm
I asked for official Chess Champion
No you didn't.