Author: Brian Katz
Date: 01:41:26 11/07/02
Go up one level in this thread
On November 07, 2002 at 03:22:18, Brian Katz wrote: >On November 06, 2002 at 18:18:41, Louis Fagliano wrote: > >>On November 06, 2002 at 16:45:51, Michael P. Nance Sr. wrote: >> >>>hello, i already have the nalimov tablebases(4 cd disc)(5 men),is this 9 disc >>>set better than the one i have now?>>>>mike >> >>Sure is. The 4-CD set contains all the 3 and 4-man nalimov tablebases plus only >>the most commonly encountered 5-man endings based on a statistical analysis of >>what occurs most often in a large database of games. >> >>This is by no means all of the 5-man nalimov tablebases there are. If you want >>every single possible 5-man end games that could legally occur then you need the >>much larger set of discs because there is no way they'd only fit on 4 CD's. >> >>Among some of the 5-man endings that are missing from the 4-CD set is king and >>queen vs. king and rook. This could occur from a king and pawn vs. king and >>rook ending where the pawn promotes to a queen. The king and queen vs. king and >>rook is left out because it doesn't occur nearly as often as a king and pawn vs. >>king and rook ending (which is on there) mainly because the losing side usually >>resigns before the pawn is promoted. >> >>But if you have only king and pawn vs. king and rook ending tablebase there >>could occur a point where your engine which is using those EGTB's will refuse to >>promote the pawn to a queen(!) because that EGTB is not there. The more >>sophisticated engines like Fritz or Crafty will promote the pawn anyway. But >>you might want to get the complete set because I don't know what engine your >>using and whether or not it will do the rather stupid thing of not promoting a >>pawn to a queen because there is no EGTB's to read. > > > I have found that in the following position, Fritz 6 and Fritz 7 will not >promote the pawn if the Nalimov 4 Disc Set is used, but Crafty will. > If only the Tablebases which came with the Fritz 6 CD are used, then Fritz >will promote the pawn. > If you don't have any Tablebases, or you hide your Tablebase Folder (Rename it >or whatever) just for the experiment, you will find that Fritz will probably >promote the pawn immediately. > >Of course once I downloaded the missing files such as KrKRR etc.,and placed them >in my Tablebase folder, Fritz then plays the endgame properly. Just to clarify this a little. Fritz without the necessary tablebase files as discussed, will check the King with the Rook for a few moves (as long as the king can't take that rook that is)and then it will eventually promote the pawn. Does anyone else find the same to be true? I have had other players on line try this experiment with the same results. I have found that turning the tablebase option off does not change the way fritz wrongly plays this endgame if the 4 disc set is used. That is why I renamed the tablebase folder for the experiment so Fritz would not find it. I have found that turning the tablebase feature off by deselecting the check box does not stop Fritz from playing various endgames properly it just prevents the long readout on your interface from showing up. Such as in the KQKR endgame. With the tablebases turned on you will see many possible moves with the various (mate in declarations) where as with the Tablebases off you won't see all of the mates in your engine window, but it should play it properly. Brian >[D]1r6/6P1/5K2/6R1/8/4k3/8/8 w
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