Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: QSearch question

Author: Robert Hyatt

Date: 15:08:03 08/27/02

Go up one level in this thread


On August 27, 2002 at 17:34:35, Patrik wrote:

>int QSearch(alpha, beta)
>{
>	...............
>	value = Evaluate();
>	if (value > alpha) {
>		if (value >= beta)
>			return(value);	<------------ My question
>		...............
>	}
>	GenerateCaptureMoves();
>	...............
>}
>
>In QSearch, if value is >= beta, it returns value without further search.
>Is this similar concept to null move in Search()?
>
>Thank you in advance.

Not quite.  The idea is this:  If you do a static evaluation and _that_
result is >= beta, there is no need to search.  Because you can always
stand pat and not play a capture and that is good enough to produce a beta
cutoff.  If you try a capture, you can only _raise_ the score, and since it is
already good enough to produce a cutoff, there is no point in wasting that
time.




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.