Search found 2903 matches

by Evert
Fri Feb 11, 2011 3:42 pm
Forum: Computer Chess Club: General Topics
Topic: What the computer chess community needs to decide
Replies: 265
Views: 63935

Re: What the computer chess community needs to decide

No offense but I don't believe you Sir. How would you know about Alpha Beta then unless you invented it. I wrote my first chess program around 1996, based on a description of how an alpha-beta search works and how you might represent a chess board on a computer in a book by Jaap van den Herik that ...
by Evert
Fri Feb 11, 2011 1:03 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

Spartacus indeed has staged move generation. It generates captures victim by victim, starting from the MVV from the opponent piece list, running through the stm piece list and doing 0x88 attack tests. A stage encompasses generation of captures of all victims of the same (approximate) value, and is ...
by Evert
Thu Feb 10, 2011 8:03 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

Incredible Spartacus still plays so well. Not searching killer moves should be a crippling bug! Sure, rub it in, why not? :P I am curious about what makes Spartacus and Nebiyu so fast compared to the other entries (it's not simply that they strong, they reach larger search depths in less time). Is ...
by Evert
Thu Feb 10, 2011 3:35 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

Even so, at some point it was even missing mate-in-3, and still evaluating as 9.6 in KQK. In the last game there was also somehing that looked suspiciously much like a search bug. In one move its score dropped from a steady 4.3 at move 37 (Spartacus ~-2) to 0.3, while indeed anyone could see it had...
by Evert
Thu Feb 10, 2011 2:15 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

Hmm, it seems Nebiyu has a bit of a problem seeing checkmates... Even at 33 ply it does not come up with mate-in-7. Some of the search depths reported by Nebiyu look insane: I've seen it claim 21 ply after a fraction of a second at timeodds against Sjaak (which was doing 13-14 ply at the same time)...
by Evert
Thu Feb 10, 2011 12:40 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

There's nothing in the eval to say that's bad. I'll add it though! I conecntrated a bit more on the Spartan eval with the last update - specifically hoplites and the structure. There's a lot of room for imrovement! When sorting the movelist I give a small bonus for castling moves, so they're tried ...
by Evert
Wed Feb 09, 2011 7:47 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Alternating Scores
Replies: 14
Views: 1645

Re: Alternating Scores

Yes without quiescence. The +7.00 is a product of my piece values which in my case are 1 3 3 7 10 for P K B R Q. So that is where those numbers are coming from. Right, I completely glossed over the fact that you're using a value of 7 rather than 5 for the rook. Any particular reason for that? Relat...
by Evert
Wed Feb 09, 2011 6:08 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Alternating Scores
Replies: 14
Views: 1645

Re: Alternating Scores

Ok I looked at the eval a little closer. To simplify, I took out everything except the material evaluation. Turns out I have the piece values set at 1 3 3.1 7 10 (for P N B R Q). I also simplified this to 1 3 3 7 10. So again from. Shouldn't matter. 5rk1/pp4p1/2n1p2p/2Npq3/2p5/6P1/P3P1BP/R4Q1K w - ...
by Evert
Wed Feb 09, 2011 2:09 am
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

The problem shows only up at the beginning at the second session, after the engine has played most moves of the first session. That is never very quick. (If you take 2 moves per session or so, the effect is not very pronounced.) If the engine would print the number of moves still left in the curren...
by Evert
Tue Feb 08, 2011 6:25 pm
Forum: Computer Chess Club: Tournaments and Matches
Topic: Thermopylay Marathon 2011 (live!)
Replies: 69
Views: 3869

Re: Thermopylay Marathon 2011 (live!)

Anyway, I hope that Catalyst and Saak can be fixed on the somewhat longer term. It should not be that hard to determine the problem: just look at the code that determines how long you are going to search. What time and movestogo parameters go in there, and are these updated properly (e.g. print the...