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Subject: Re: Root Position

Author: Gian-Carlo Pascutto

Date: 07:23:26 01/05/01

Go up one level in this thread

On January 05, 2001 at 09:45:47, Robert Hyatt wrote:
>>I notice I sometimes when I get a fail low at the root, I do a research, and
>>then get a fail high! The most likely explanation is that I am a moron and it >>is bug. Can you think of another explanation? Or an easy way to catch this
>>bug?
>
>this is not common, but perfectly normal, and it can't really be avoided.

Since this happens a lot in my program, I spent some time tracking down
what were the minimal conditions:

- aspiration window (no fail high/low otherwise)
- null move
- hash table used for move ordering (not for scores, not even on exact matches)

Now it still isn't making sense to me...how can you produce a different
_score_ anywhere in the tree by just altering move ordering??

Anybody who knows an explanation here? 'You _must_ have a bug' is acceptable
too.

--
GCP

• Re: Root Position Andrew Dados 11:23:14 01/05/01
• Re: Root Position Robert Hyatt 11:00:58 01/05/01
• Re: Root Position Heiner Marxen 09:12:29 01/05/01
  • Re: Root Position Gian-Carlo Pascutto 09:23:06 01/05/01
    • Re: Root Position Severi Salminen 12:10:47 01/05/01
      • Re: Root Position Gian-Carlo Pascutto 15:07:05 01/05/01
        • Re: Root Position Severi Salminen 00:37:38 01/06/01
• Re: Root Position Dieter Buerssner 08:22:14 01/05/01
  • Re: Root Position Gian-Carlo Pascutto 08:57:53 01/05/01

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