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Subject: Re: How I Learned to Stop Hating 141

Author: Tord Romstad

Date: 07:39:27 09/03/04

On September 03, 2004 at 10:20:38, Stuart Cracraft wrote:

>My mate threat is broken. The null move before it is searching with
>a window of -beta+1,beta and Tord says he wouldn't do that.

I think I should clarify this.  In most programs, there is no reason
to use anything more than a minimal window in the null move search.
The code would resemble this:

   null_value = -search(-beta, -(beta+1), depth-(R+1)*PLY);

I hope this is what you meant to say above, and that your -beta+1,beta
was a typo.

However, if you want to use the null move search to do Botvinnik Markoff
extensions or similar tricks, it might be a good idea to increase the
window size.  This will make the null move search slightly more expensive,
but you will also get slightly more information back.  The code would
look like this:

   null_value = -search(-beta, -alpha, depth-(R+1)*PLY);

Tord

Re: How I Learned to Stop Hating 141 Richard Pijl 07:48:53 09/03/04
- Re: How I Learned to Stop Hating 141 Tord Romstad 08:02:24 09/03/04
  - Re: How I Learned to Stop Hating 141 Antonio Dieguez 08:22:22 09/03/04

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