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Subject: Re: Fail-hard, fail-soft question

Author: Dan Honeycutt

Date: 23:02:28 05/06/04

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On May 07, 2004 at 00:30:52, Russell Reagan wrote:

>On May 06, 2004 at 17:16:37, Dan Honeycutt wrote:
>
>>Would seem what you hash is more important than what you return.  ie with a
>>window of 1, 2 I get back a score of 50.  The move at the previous ply fails low
>>whether I return 2 or 50.  But later I come to the same position with a window
>>of 25, 26.  If I have hashed the 50 I'll get a cutoff but if I hashed the 2 I
>>won't.
>>
>>Dan H.
>
>Hmmm. What about the opposite? You search with a window of 1,2 and get back a
>score of -50. Later you search with a window of -25,-26. If you stored a 1, you
>get a cutoff. If you stored the -50, you don't.

No, works the same.  I cut if lower bound >= beta or upper bound <= alpha.  The
+50 is stored as a lower bound.  If the best I get back is -50 it's stored as an
upper bound so if -26, -25 shows up later I still cut whereas if I had stored
the 1 I wouldn't.

Dan H.



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