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Subject: Re: Pruning problems still...

Author: Will Singleton

Date: 11:28:06 09/17/98

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On September 17, 1998 at 09:07:50, Jari Huikari wrote:

>On September 14, 1998 at 16:39:15, Robert Hyatt wrote:
>
>>... If your move ordering is good, the first move should be better than
>>the second, correct?  To confirm this, you search the second move, but again,
>>if your move ordering is good, you quickly find a move by your opponent that
>>"refutes" this move and you can stop as soon as you find a ply=2 move that
>>produces a score that is worse for you than the score for the first move
>>you searched.
>
>I do exactly this. Even tried with cutoffs only at ply=2, which certainly
>_should_ work. But still it produces those strange sacs. :-<
>
>					Jari


When I was (am) struggling with bugs involving the search, I find it helpful to
write the search out to a diskfile.  Usually that will reveal what's going on,
but it takes some time to wade through it.

Example, for a 3 ply search:

1  a4
   2  Kg2
      3  a5  score = 100
      3  b5  score = 50
   2  kg2 score = 50
   2  kh2
      3  b5  score = 20
      3  a5  score = 60 cutoff
   2  kh2 (was cut)
1  a4 score = 50




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