Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Why using Zobrist keys for Pawn Hasing?

Author: Ratko V Tomic

Date: 08:53:10 12/05/01

Go up one level in this thread


>The problem is that you have 56 bits of information.  48 possible pawn
>positions + 8 possible en passant target files.

En passant needs at most 3 bits. On average it would need much
less than even the 3 bits since after the position of pawns is
specified, the en passant bits (0-3 bits) may be added
conditionally as an index into the array of en passant
candidates. The 48 bits specifying the pawn position thus
automatically specify how many en passant bits follow.



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.