Calculate a mate in 95?! Are you nuts! Those tablebases sound cray cray!
Double Check to Make Sure Your Tablebases are Working
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Thanks for the tip, Ed!
You might also want to check all of the tablebase files to ensure that none of them are corrupt. I used to worry when I copied the tablebase files to a new location that maybe not all of the files got copied 100% perfectly. At one time I used the Wilhelm chess program to check the integrity of the tablebase files, but I think I've figured out a simpler, better way.
I obtained the MD5 hash file for the tablebase files (usually also available from the tablebase download site), and I also obtained a copy of the freeware program named Md5Checker. There's no installer for this program; It's a portable, standalone executable. (Link: http://getmd5checker.com/ ) I simply added the tablebase MD5 hash file and the Md5Checker.exe executable to the folder containing the tablebase files.
Now, any time I copy or move the tablebase file folder, the Md5Checker files also get copied. (You can leave these files in the tablebase folder permanently; They don't interfere with the operation of the tablebases.) Then all I have to do after copying the tablebase files is to start up the Md5Checker program and quickly check the files against the hash file. It only takes about a minute to do this check.
Haha, doublecheck, i get it
Hi
Most of you probably have the Gaviota or the Nalimov endgame tablebases (or both) installed with your favorite GUI.
You probably have the 3-4-5 bases installed and possibly some of the more common 6-piece endgame tablebases installed too.
Now and then you should double-check to make sure the engine and GUI and the bases are working as desired. (At times, something might get out of whack, with your programs or folder structure or whatever, and if so the bases might won't work at all, and you might not even know it.)
Here's a position to test to see if everything is working correctly. Enter this position in your favorite GUI, and then fire up your favorite engine. (This assumes your favorite engine supports tablebases.)
Your engine should report a mate in 95 INSTANTLY, begining with 1.Nd3. The engine won't evaluate the position at all.
Note that White only has two winning moves. 1. Nd3, with a mate in 95, and 1. Nd1, for a mate in 96. All other moves draw with correct play by Black.
Interestingly enough, Black will Queen his h-pawn... but White delivers mate on the next move.