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Subject: Re: rewriting alpha beta(thanks in advance for advices)

Author: Uri Blass

Date: 06:55:59 12/11/03

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On December 11, 2003 at 09:41:38, Tord Romstad wrote:

>On December 11, 2003 at 08:29:08, Robert Hyatt wrote:
>
>>On December 11, 2003 at 06:44:06, Uri Blass wrote:
>>
>>>1)When do you calculate extensions
>>
>>Inside the loop where I choose and make a move and then recursively
>>call search.  That is where I notice that the move is the only legal
>>move, or the move checks the opponent, or pushes a passed pawn, etc.
>
>I used to do like this, too, but changed it because it was not flexible
>enough.  At that stage in the search, you simply don't know enough about
>the move to make an intelligent decision about how much to extend it.
>You can identify simple stuff like checks, check evasions, passed pawn
>pushes and so on, but nothing more sophisticated.
>
>I now extend at the beginning of the search, directly after the call to the
>static evaluation function.  The advantage of doing like this is that you
>know much more about the effect of the move, because you can look at how
>the move played affected the various components of the evaluation function.
>
>Tord

There is no difference for me because my makemove also calculates evaluation.
The problem is that I calculate the extensions in the beginning of alphabeta
and it means that if I call twice alphabeta from itself without making moves I
may distort data.

Maybe I can correct it by making 2 null moves but I do not like this solution
and I think that I simply need to change the alphabtea function.

Uri



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