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Nalimov egtb probing code

Posted: Mon May 16, 2016 8:41 pm
by Fabio Gobbato
Where can I find the probing code for the Nalimov egtb?

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 8:49 pm
by Joost Buijs
You can find it in the Crafty source code, you'll need permission from Eugene Nalimov and Andrew Kadatch to use it.
Nowadays most people use Syzygy, but it is nice to have distance to mate information, with SSD's getting cheaper the larger size of Nalimov egtb is not such a big problem anymore.

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 8:50 pm
by Vinvin
Fabio Gobbato wrote:Where can I find the probing code for the Nalimov egtb?
Probably in Crafty. But you have to get the permission of Eugene Nalimov to release your code with it.

egtb.cpp in the source here http://www.craftychess.com/crafty-25.0.1.zip .
Found here http://www.craftychess.com/

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 8:56 pm
by yurikvelo
reference implementation by Eugene Nalimov and Robert Hyatt was realized in Crafty, with Tablebases and probing code available
https://www.cis.uab.edu/hyatt/crafty/source/

probe.c

Code: Select all

 *******************************************************************************
 *                                                                             *
 *  EGTBProbe() is the interface to the new tablebase code by Eugene Nalimov.  *
 *  This is called from Search() after a capture, when the number of pieces    *
 *  remaining on the board is less than or equal to the max number of pieces   *
 *  we have in the EGTB files that are available for use.                      *
 *                                                                             *
 *******************************************************************************

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 9:23 pm
by Nordlandia
Joost Buijs wrote:You can find it in the Crafty source code, you'll need permission from Eugene Nalimov and Andrew Kadatch to use it.
Nowadays most people use Syzygy, but it is nice to have distance to mate information, with SSD's getting cheaper the larger size of Nalimov egtb is not such a big problem anymore.
I wish there were "Stockfish Matefinder" with Nalimov support.

Yes, indeed Nalimov still has it use today. Although big and cumbersome/clumbsy.

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 9:34 pm
by velmarin

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 9:50 pm
by hgm
Nordlandia wrote:I wish there were "Stockfish Matefinder" with Nalimov support.

Yes, indeed Nalimov still has it use today. Although big and cumbersome/clumbsy.
Why not use Gaviota EGTs?

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 9:55 pm
by Nordlandia
hgm wrote:
Nordlandia wrote:I wish there were "Stockfish Matefinder" with Nalimov support.

Yes, indeed Nalimov still has it use today. Although big and cumbersome/clumbsy.
Why not use Gaviota EGTs?
Gaviota is 10% less in space.

Hardly a difference at all. Also 6-Men do not exist in that format.

You mean for Stockfish, i'm not 100% certain but Stockfish do not support Gaviota.

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 10:00 pm
by hgm
Nalimov probing code is not compatible with the GPL, so Stockfish or Stockfish derivatives can NEVER get permission to use it. For Gaviota EGT you don't have that problem.

Re: Nalimov egtb probing code

Posted: Mon May 16, 2016 10:03 pm
by Nordlandia
Custom stockfish version with Gaviota support is handy indeed for endgame studies and such inolving mate in x numbers.

Depth To Mate over Syzygy is more appealing.