Author: Kevin K
Date: 16:39:56 09/03/05
Go up one level in this thread
On September 03, 2005 at 18:11:23, A. Cozzie wrote: >On September 03, 2005 at 18:06:05, Robert Hyatt wrote: > >>On September 03, 2005 at 17:05:36, Kevin K wrote: >> >>>Hello, Dr. Hyatt. >>> >>>1 d2-d4 d7-d5 2 e2-d4 >>>1 e2-d4 d7-d5 2 d2-d4 >>> >>>These two moves are considered the same in transposition table, >>>because resulting positions are the same. >>>But, what about in book database? >>>As far as I know, Crafty does not consider these the same positions in book. >>>Why not? >>>For example, if I have only 1 d2-d4 d7-d5 2 e2-d4 e7-e6 in book and >>>if I play 1 e2-d4 d7-d5 2 d2-d4, Crafty does not find next move(e7-e6) >>>from book even though two positions are the same. >>> >>>Thank you. >> >> >>A book position is based on the parent position and the child position. That >>is, the position before the move and the position after the book. >> >>This was done to avoid a well-known transposition "bug".. > >Probably not well known to him, Bob :) > >If you do the book purely based on position you can get problems like this >example (the program being black) > >1. e4 e5 2. Bb5 a6 3 Nf3 Nc6?? > >anthony I know what you mean. But, 1. e4 e5 2. Nf3 Nc6 3 Bb5 and 1. e4 e5 2. Bb5 a6 3.Nf3 are different positions. Positions just before final position must be the same. This doesn't seem good example.
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.