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Subject: Re: 6-man TBs

Author: Marc Bourzutschky

Date: 12:30:42 02/02/05

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On February 02, 2005 at 13:19:11, Anthony Cozzie wrote:

>On February 02, 2005 at 13:14:21, Dieter Buerssner wrote:
>
>>On February 02, 2005 at 13:00:51, Anthony Cozzie wrote:
>>
>>>On February 02, 2005 at 01:06:30, Robert Hyatt wrote:
>>>
>>>>>KRPKRP (only the white-side is available from Bob right now?)
>>>>
>>>>think about it.  If pieces are symmetric you only need one side.  Just turn your
>>>>white pieces into black ones, and the black ones into white ones, and look it
>>>>up.  :)
>>>
>>>doh :(
>>
>>Bob forgot to mention the mirroring needed for positions with pawns. The pawn
>>TBs are not identical (they have the identical contents, of course, ordered a
>>bit differently).
>>
>>C:\tb>dir kpkp*
>>
>>05.08.2003  12:00         1.111.988 kpkp.nbb.emd
>>05.08.2003  12:00         1.116.299 kpkp.nbw.emd
>>
>>I think, current Nalimov code needs both (which may be not intended). From the
>>code:
>>
>>	TB (kpkp, false, false, false, (T22<P, P>::IndCalcW), (T22<P, P>::IndCalcB),
>>3863492, 3863492)
>>
>>The "fsym" is set to false.
>>

For the 33p endings the redundancy is eliminated, with IndCalcB replaced by
IndCalcBF which does the appropriate flipping.  That is something I added to the
code.  Eugene was skeptical at first that this would work, but he seems to have
come around :-)  For kpkp the redundancy is no big deal, so there was no need to
eliminate it.

-Marc



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