Search found 26 matches

by John Major
Sun Dec 04, 2011 1:26 pm
Forum: Computer Chess Club: General Topics
Topic: question about speedup when starting a test position
Replies: 16
Views: 1306

Re: question about speedup when starting a test position

The branch prediction also needs warm-up, besides caches and hash. This is a problem with processor simulation.
by John Major
Sat Nov 26, 2011 1:11 pm
Forum: Computer Chess Club: General Topics
Topic: Someone worked hard, someone else not.
Replies: 35
Views: 4734

Re: Someone worked hard, someone else not.

Oh, I know this game, let me try too! Someone worked hard , spending tens of thousands of hours creating an engine. He spent a few dozen of them resolving a specific bug somewhere deep in the transposition table which made the engine fail in certain positions. This someone also solved hundreds of i...
by John Major
Tue Nov 15, 2011 11:35 pm
Forum: Computer Chess Club: General Topics
Topic: Houdini analysis in Fritz 13--strange.
Replies: 12
Views: 2057

Re: Houdini analysis in Fritz 13--strange.

Image
Houdini has the best logo of them all. Reminds me of Derren Brown.
by John Major
Sun Nov 13, 2011 10:57 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Want to know what savings to expect with pruning methods...
Replies: 23
Views: 3423

Re: Want to know what savings to expect with pruning methods

What do you guys recommend I should do next now? - null move, easy to get quick results - LMR, also quick results, but can weaken your engine - TT, difficult to get right, worth it - PVS, easy - futility, initially easy, I'd skip this - Aspiration windowing, difficult to get right, I'd skip this - ...
by John Major
Sun Nov 13, 2011 8:24 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Want to know what savings to expect with pruning methods...
Replies: 23
Views: 3423

Re: Want to know what savings to expect with pruning methods

Right now my engine can reach up to ply 8 (not including Q search) in about 20 seconds on avg. The only saving features I have is: MVV/LVA move ordering and killer. My question is does 8 ply at 20 seconds sound right? Is it too slow? Sounds right What type of savings can I expect with each? Transpo...
by John Major
Wed Sep 14, 2011 12:55 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: perft conflict...
Replies: 13
Views: 2422

Re: perft conflict...

In i-perft check evasions are wrong: user@dell:~/i-perft$ wine i-perft.exe -divide 1 "rn1qkbnr/p1pppppp/b7/8/1p2P3/P7/1PPPKPPP/RNBQ1BNR w kq - 2 4" i-perft 1.0 (c) 2006-2008 AJ Siemelink +---+---+---+---+---+---+---+---+ 8 |*r*|*n*| |*q*|*k*|*b*|*n*|*r*| +---+---+---+---+---+---+---+---+ 7 |...
by John Major
Sat Aug 20, 2011 11:52 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: My Engine won't pick up PV's until depth >= 10
Replies: 14
Views: 2682

Re: My Engine won't pick up PV's until depth >= 10

Sven Schüle wrote:
John Major wrote:'Key' in zobristKey() is used uninitialized.
That is due to the "x ^ y" instead of "x ^= y" kind of bugs in that routine which I mentioned.

Sven
No, uninitialized is uninitialized.
by John Major
Sat Aug 20, 2011 11:07 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: My Engine won't pick up PV's until depth >= 10
Replies: 14
Views: 2682

Re: My Engine won't pick up PV's until depth >= 10

Your futility pruning must do take back before returning alpha. f_prune is not initialised. Why should it even return? I guess it should only skip the current move (after calling TakeBack which I initially missed). Sven True, I had overlooked that. I also got compile errors/warnings with g++ in Lin...
by John Major
Sat Aug 20, 2011 9:49 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: My Engine won't pick up PV's until depth >= 10
Replies: 14
Views: 2682

Re: My Engine won't pick up PV's until depth >= 10

...and now my QSearch is causing an explosion :x Some observations: Your null move score = -AlphaBeta(depth - 1 - R, 1 - alpha, 0 - alpha, &line); causes assert(beta > alpha) on top of AlphaBeta() to fail. It should be something like this: score = -AlphaBeta(depth - 1 - R, -beta, -beta ...