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Subject: Re: what is the result of your qsearch here?

Author: Leen Ammeraal

Date: 11:53:16 01/14/02

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My program 'sees the mate', but it does not if
there is no black pawn on h7, because then
Qh7 is not a capture move. So I think there
is very little for me to be proud of.
It seems pointless to me to worry about a
program not seeing the mate here without you
also paying attention to the same position
without this pawn on h7.
Leen



On January 14, 2002 at 08:24:29, Uri Blass wrote:

>[D]5rk1/5p1p/pp3p1Q/5B2/1P6/P4bP1/7P/6K1 w - -
>
>
>Assume that beta=10000 that is a mate score.
>
>The result of my qsearch is today depends on alpha
>
>If alpha is small enough then my qsearch can see the mate because it does
>Qxh7# and find that black has no legal moves.
>
>If alpha is not small enough then the move Qxh7# is pruned by my qsearch as not
>better than alpha so the result is alpha.
>
>The result is that it is possible for me to get a fail high and after it fail
>low.
>
>usually it does not happen so maybe it is better to start with
>alphabeta(score-30,score+30,depth)
>after fail high to do alphabeta(score+29,mate,depth)
>and only if I get faillow to do alphabeta(score-30,mate,depth)
>
>What is your opinion?
>
>Uri



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