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Subject: Re: KQQKQQ EG-db: existence and availability

Author: Eugene Nalimov

Date: 17:01:30 09/22/99

Go up one level in this thread


One more thing: you'll be able to use TB name where first dot is replaced by
underscore. Probably that will reduce number of questions "I downloaded a lot of
TBs, but Crafty does not see them".

Eugene

On September 22, 1999 at 19:53:14, Robert Hyatt wrote:

>On September 22, 1999 at 09:50:08, Robert Hyatt wrote:
>
>I have gotten the new tbindex stuff into crafty.  I will try to release a new
>version later tonight that has this.  It will probably have everything current
>except for the new majority stuff I am still tweaking.
>
>Latest version has three improvements of interest:
>
>1. it outputs 'insane' (or redundant) FEN.  :)  Every rank has 8 squares
>specified, no trailing "/".
>
>2. You can just cut and drop fen right into crafty without the 'setboard' on
>the front.  It will take it just fine.  If the position is a known tablebase
>position, it will give you the full mating/drawing line automatically (I may
>disable this later, see 3 below)
>
>3.  there is another use for the 'egtb' command.  after using it to enable
>tablebases, you can say "egtb" and get the full (optimal) PV for the current
>position, if it is a TB position.  If you say "egtb !" it will append a ! to
>any move where there is only one best choice and all others are inferior...
>
>More later...
>
>
>
>
>
>>On September 22, 1999 at 09:35:46, guy haworth wrote:
>>
>>>This note contains a request - for Robert Hyatt I think ...
>>>
>>>As CCC readers may be aware, Eugene Nalimov and Christoph Wirth have
>>>independently created a complete and self-consistent KQQKQQ endgame database.
>>>
>>>Both authors responded readily to the request of the World TEam (in GK-v-WT) and
>>>their achievements are without parallel.  Many thanks and warmest
>>>congratulations to both.
>>>
>>>Eugene's is optimised to DTM (distance to mate)and Christoph's to DTC (capture
>>>or mate).  However, they can clearly be used to second-source each other on the
>>>value of a KQQKQQ position.  This gives more authority to both databases.
>>>
>>>A number of players involved in the Kasparov-v-WorldTeam event (and others) will
>>>now be thinking of using this KQQKQQ database and this leads to thoughts about
>>>the practicality of doing this.  There appear to be two issues.
>>>
>>>The KQQKQQ database is a 6-man rather than a 5-man database and as such, I
>>>understand requires a modification to standard CRAFTY.
>>>
>>>It is also a very large database (407503Kb) and is presumably difficult to
>>>download in the standard way.
>>>
>>>May I ask Robert to define on this CCC board how to make the modifications to
>>>CRAFTY to use 6-man EGs ... and how the KQQKQQ database itself may be best
>>>acquired.
>>>
>>
>>
>>There are two parts to this.  I haven't done them yet, because I am in the
>>middle of testing the pawn-majority code I have added, and I try to limit
>>changes to one area to avoid going nuts debugging.
>>
>>1.  the actual source for crafty doesn't have to be changed.  I fixed this
>>months ago.  Eugene reports the number of pieces I should use to probe the
>>databases and I use this number.  If you put a 6 piece file out there, I'll
>>probe it.
>>
>>2.  egtb.cpp is the place where it must be changed.  This needs to have the
>>old probe code of his removed (the tbindex stuff) and the new code added (the
>>new code is on the ftp machine in tbgen_nw.zip).  That is the only real change
>>and it should be easy.  It will hopefully become a part of the next version if
>>I have time to merge it in, since it doesn't slow anything down (it will take
>>a special compile to enable 6 pieces probably, I don't know what including their
>>support will do memory-wise if you don't have any.  Eugene?)
>>
>>
>>
>>
>>
>>
>>
>>>
>>>As a footnote, both Eugene and Christoph 'warmed up' their codes on KNNKNN and
>>>KRRKRR.  Eugene later produced a KBBKBB EG-db as well.  All four of Eugene's
>>>datbases are on ftp://ftp.cis.uab.edu/pub/hyatt/TB/.
>>>
>>>As a technical footnote, Eugene used a Compaq Alpha procesor with 4GB RAM and
>>>ran the problem 'in store'.  Christoph had 1GB RAM and therefore sustained some
>>>100GB of 'paging' disc traffic.  Both databases are post-hoc checked to ensure
>>>that the value/depth of a position is consistent with that of its successors.
>>>
>>>Again, thanks and congratulations to both Eugene Nalimov and Christoph Wirth.



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