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Subject: Re: SEE and pin detection

Author: Martin Giepmans

Date: 04:06:17 08/31/04

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On August 31, 2004 at 06:52:10, Vasik Rajlich wrote:

>On August 30, 2004 at 19:44:50, Eugene Nalimov wrote:
>
>>On August 30, 2004 at 14:03:49, Dan Honeycutt wrote:
>>
>>>In spite of Dr. Hyatt's admonishment that this was a loser in Crafty, I'm bent
>>>on trying it.  Since I do legal move generation I can do the pins for half price
>>>- I either have or can use the pin data for one side in conjunction with
>>>generating moves.  I just finished the routine.  My NPS dropped by just over 4%
>>>on bench test psitions.  I've just started testing an hope to have some
>>>indication if pin detection is a win, lose or draw in a few days.
>>>
>>>One aside - the pin detection is not always more accurate (or mine isn't).  In
>>>the following position for the move Nxg5 the no-pin SEE correctly returns +1
>>>where the pin-detection SEE comes back with -2.
>>>
>>>[D] 7k/4q3/8/6p1/4N3/5N2/8/4K3 w - -
>>
>>
>>White is lost in 24 :-)
>>
>>Thanks,
>>Eugene
>
>Really? This ending is only lost in exceptional cases - and it's certainly not
>obvious that this is one of them.
>
>Vas

I guess Eugene has the (6 pieces) EGTB for this one. :)

Martin


>
>>
>>>Fixing this would require keeping track if the pinning piece enters the
>>>exchange, which I'm afraid would bee too expensive.
>>>
>>>Dan H.



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