Author: Les Fernandez
Date: 22:47:41 10/18/01
Go up one level in this thread
On October 19, 2001 at 01:20:38, Dann Corbit wrote: >For pawnless and rookless tablebase files: > >The name of the file tells the pieces (e.g. KBBKQ) >Side-to-move King, Bishop, Bishop >Side-not-to-move King, Queen >No bits needed to encode this data. > >Then, 5 bits for the positions of the pieces (0-63) times the 5 pieces = 25 bits > >This is the key (the above 25 bits). >So for any tablebase of this format, there are 2^25 entries. > >The answer is encoded as follows: >Then the move to make (which we can encode in 8 bits -- the move number from 0 >to 255 considering the moves as sorted lexically or as output by a specific move >generator.) > >Then we need status: >Won/Loss/Drawn/Broken -- > 4 states means 2 bits. > >That is 12 bits. So any pawnless/rookless tablebase file will need a total of: >12*(2^25) = 402653184 bits = 50,331,648 bytes before compression. > >How does this compare with a decompressed 5 piece Nalimov tablebase file? > >For positions with rooks or pawns, we could just use a format like the current >one. > >Seems like it might be a real big win for 6,7,8 man tablebase files. Each file >will be exactly 5 times larger than the file one generation before it before >compression. > >So a 6 man tablebase file would take 250 megs before compression. >And a 7 man tablebase file would take 1250 megs before compression. >etc. > >Is my brain the cause of pain because the notion is insane? Dann at first glance your idea appears to have merit. Could you imagine the effect this could have on egtb's!!! Instead of a factor of (I think) 60 vs 5?? I am beginning to salivate already. Up front your concept seems valid and now its time for the wolf-pack out here to tear into it!!! Eugene, Bob, Bruce, calling all cars lets take a look at this!!! Hurry. Excellent idea lets see what happens.
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.