Search found 530 matches

by Zenmastur
Sat Oct 04, 2014 7:31 am
Forum: Computer Chess Club: General Topics
Topic: Probably the strongest chess engines are private
Replies: 30
Views: 6841

Re: Probably the strongest chess engines are private

Larry, would you say that the strongest versions of Komodo and Stockfish on 16 cores or more can beat the Rybka cluster which has more than 296 cores at LTC or rapid chess? Best regards! I really don't have much info on the Rybka cluster. Offhand I wouldn't think that a 16 core machine with Komodo ...
by Zenmastur
Wed Aug 06, 2014 7:41 pm
Forum: Computer Chess Club: General Topics
Topic: Advice on building Chess computer
Replies: 14
Views: 3614

Re: Advice on building Chess computer

An ASUS KGPE-D16 SSI EEB mother board supporting two AMD Opteron 6344 Abu Dhabi 2.6GHz 12-core Socket G34 Processors would seem to offer more performance for about the same money as an Intel rig. The cpu's can be had for about $360 each and the motherboard for about $410.

Regards,

Forrest
by Zenmastur
Thu Jul 17, 2014 2:51 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Upper bound on proof tree size
Replies: 43
Views: 5415

Re: Upper bound on proof tree size

Yeah, you shouldn't do that. As the rest of us know, a tree is a woody perennial plant, typically having a single stem or trunk growing to a considerable height and bearing lateral branches at some distance from the ground. :wink: Unless we are talking about banana trees, in which case they resembl...
by Zenmastur
Wed Jul 16, 2014 11:36 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Upper bound on proof tree size
Replies: 43
Views: 5415

Re: Upper bound on proof tree size

As a topologist, it's hard to call an object a "tree" if it contains cycles, even undirected ones. :) Well, I'm not a topologist, I'm a person and I intend to remain one for the rest of my life. Second, I can hardly be blamed if people choose to name objects with words that don't describe what they...
by Zenmastur
Wed Jul 16, 2014 10:33 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Whats the easies way to make crafty ignore the 50 move rule?
Replies: 11
Views: 2030

Re: Whats the easies way to make crafty ignore the 50 move r

Crafty, or any other engine, is pretty useless for analysing a long TB endgame. I guess that depends on what information you're trying to obtain from the analysis. Example, if you want to know how many of the moves by the losing side result in short mates it's irrelevant if the engine sees to the e...
by Zenmastur
Wed Jul 16, 2014 8:21 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Upper bound on proof tree size
Replies: 43
Views: 5415

Re: Upper bound on proof tree size

A better estimate of the maximum number of nodes in a proof-tree (a DAG by any other name would smell as sweet) appears to be: MAX_Nodes = 2 * sqrt( Number_of_possible_descendants ) / sqrt( b - 1 ) Where: b is the branching factor if known. If b is unknown then any reasonable estimate can be used wi...
by Zenmastur
Tue Jul 15, 2014 8:18 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Whats the easies way to make crafty ignore the 50 move rule?
Replies: 11
Views: 2030

Re: Whats the easies way to make crafty ignore the 50 move r

That will screw up other things like repetition checking. The first question I would ask is "why"? The 50 move rule is part of the official rules of the game, disabling it doesn't make any sense. Any more than disabling castling or en passant or whatever? If I were going to disable it, I would prob...
by Zenmastur
Tue Jul 15, 2014 6:45 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Upper bound on proof tree size
Replies: 43
Views: 5415

Re: Upper bound on proof tree size

Ben,

Is source or an exe available for your program?

I know that I don't like giving-up code I have written so I'll understand if the answer is no.

Thanks,

Zen
by Zenmastur
Tue Jul 15, 2014 6:39 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Upper bound on proof tree size
Replies: 43
Views: 5415

Re: Upper bound on proof tree size

I can prove that this is mate-in-3 by presenting a tree with 26 nodes (this includes a root node representing the position itself). I don't see how any proof-tree for this position could have fewer nodes than this. Of course, some of these nodes represent the same position, but they are still disti...
by Zenmastur
Mon Jul 14, 2014 6:19 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Upper bound on proof tree size
Replies: 43
Views: 5415

Re: Upper bound on proof tree size

I think you've simply discovered a statement of the well-known fact that, with perfect move ordering, an alpha-beta search reduces the size of the search tree from b^d to about sqrt(b^d). Actually, isn't the content of this already visible in the formula I posted? I certainly used the fact that onl...