Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Shredder 7.04 6 Piece EGTBs?

Author: Drexel,Michael

Date: 04:56:05 01/15/04

Go up one level in this thread


On January 15, 2004 at 07:41:22, Mike Hood wrote:

>On January 15, 2004 at 04:17:34, Drexel,Michael wrote:
>
>>On January 14, 2004 at 18:57:50, Mike Hood wrote:
>>
>>>On January 14, 2004 at 16:08:24, David H. McClain wrote:
>>>
>>>>On January 14, 2004 at 15:07:39, Chris Taylor wrote:
>>>>
>>>>>Does S8 know how to use the 6 piece egtbs'?  I could wait for it to arrive, nah;
>>>>>please tell me!  I have ordered the dam things and would like to know if I have
>>>>>wasted my GBPs.
>>>>>
>>>>>
>>>>>Chris
>>>>
>>>>Chris,
>>>>
>>>>Being an amatuer here perhaps I am making an incorrect assumption about this.
>>>>
>>>>When I use my Shredder 7.04 the heavy hard drive activity appears to indicate it
>>>>is accessing EGTBs tablebases when there are six pieces left on the board.  I
>>>>have assumed all along that this indicates that Shredder 7.04 is using a few of
>>>>my 6 piece EGTBs or is at least looking for them.  Shredder Classic GUI also
>>>>states "6 piece EGTBs found" when changing hash table size for them.
>>>>
>>>>Hopefully one of our experts on this can either confirm or refute this.  If this
>>>>is in fact true then I see no reason why S 8 would not do the same.
>>>>
>>>>DHM
>>>
>>>The disk activity (and the "tb=" info in the engine window) when 6 pieces are on
>>>the board doesn't necessarily mean that Shredder 7 is accessing a 6-piece
>>>tablebase. It might only be accessing 5-piece tablebases in a search line which
>>>results in the capture of one of the pieces.
>>>
>>>As far as I know, Shredder 7 accesses the single part 6-piece tablebases, ie the
>>>tablebases that don't have a digit in the filename. The only programs that I
>>>know that access the multi-part 6-piece tablebases are Hiarcs 9 and Crafty. I
>>>assume that Shredder 8 can be added to this list. Ask me again next week.
>>
>>You can add Fritz 7 and Fritz 8 to that list.
>>
>>Michael
>
>Sorry, Michael, you're wrong.

No, I am right. Both Fritz 7 and Fritz 8 use them in the search.

New game
3kr3/8/8/8/8/3p4/2PP4/2RK4 w - - 0 1

Analysis by Fritz 7:

1. = (0.00): 1.Ta1 dxc2+ 2.Kxc2 Te2 3.Ta7 Te1
2. = (0.00): 1.Tb1 dxc2+ 2.Kxc2 Te2
3. = (0.00): 1.cxd3 Te5 2.d4 Td5
4. -+ (-#28): 1.c3 Th8 2.Ke1
5. -+ (-#21): 1.c4 Tg8 2.Ke1


New game
3kr3/8/8/8/8/3p4/2PP4/2RK4 w - - 0 1

Analysis by Fritz 8:

1. = (0.00): 1.cxd3 Kd7
2. = (0.00): 1.Ta1 dxc2+ 2.Kxc2
3. = (0.00): 1.Tb1 dxc2+ 2.Kxc2
4. -+ (-#27): 1.c3 Tg8 2.Ke1 Tg1+ 3.Kf2 Txc1 4.Ke3 Te1+ 5.Kd4 Te2 6.Kxd3
5. -+ (-#21): 1.c4 Th8 2.Ke1 Th1+ 3.Kf2 Txc1 4.Ke3 Txc4 5.Kxd3 Tc1 6.Kd4


This is what you get if an engine does not use them:

New game
3kr3/8/8/8/8/3p4/2PP4/2RK4 w - - 0 1

Analysis by Fritz 6:

1. ± (1.38): 1.cxd3 Kd7 2.Tc5 Kd6 3.Ta5 Kc6 4.d4 Te4 5.d5+ Kb6
2. = (0.00): 1.Tb1 dxc2+ 2.Kxc2
3. = (0.00): 1.Ta1 dxc2+ 2.Kxc2
4. -+ (-#27): 1.c3 Th8 2.Ke1 Th1+ 3.Kf2 Txc1 4.Ke3 Te1+ 5.Kd4 Te2
5. -+ (-#21): 1.c4 Th8 2.Ke1 Th1+ 3.Kf2 Txc1 4.Ke3 Txc4

Michael



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.