Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Opening Book PGN's

Author: Koundinya Veluri

Date: 12:51:00 12/02/01

Go up one level in this thread


On December 02, 2001 at 12:53:18, David Rasmussen wrote:

>On December 02, 2001 at 12:45:35, Koundinya Veluri wrote:
>
>>On December 02, 2001 at 12:16:57, David Rasmussen wrote:
>>
>>
>>Hi David,
>>
>>A threshold of 5 games might be too big for the 2600u collection because it has
>>already been cleaned several times. 1 worked well for me, even 2 removed too
>>many variations from the book, but all depends on how the program chooses which
>>positions to store of course. But if the program has a good algorithm for
>>picking book moves, then a threshold of 1 should do. I created one from 2600 for
>>my program (although it doesn't have win percentage yet) with a threshold of 1
>>game to 60 plies. It has about 1.2 M positions and rarely comes out of book with
>>an obviously lost position. Also, if you use a threshold of 1 game, you might
>>also want to reduce the ply count to 30 or 40.
>>
>>You can also try Enormous.pgn from the Crafty FTP site if you really want a
>>near-1GB pgn file, but there are many sizes of pgn collections there. For the
>>enormous, a threshold of anywhere from 2 games to 5 games works well for me.
>>
>>Crafty FTP: ftp://ftp.cis.uab.edu/pub/hyatt/
>>Look in the common folder.
>>
>

>Thanks for the info! My problem with a low threshold was that below 6, 2600u
>contains 1. a3 . WHY??
>
>I will try with enourmous.pgn and 2600u with a lower threshold, and just live
>with 1. a3, then...
>
>/David

Hi David,

The 1. a3 games are probably there so that programs can reply to it from the
opening book. I don't store any moves that are played close to 0% of the time so
my program will never play 1. a3 but it will be able to reply to it from the
book.

Regards,
Koundinya



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.