Help Create Tiny Opening Book for GNUchess (to vary play)

[chessdev]

ok great! did you use that to generate the smaller books? can you tell me what paramters you used? thank you so much!!

[Dann Corbit]

ok great! did you use that to generate the smaller books? can you tell me what paramters you used? thank you so much!!

I put the file into SCID.
To make the smaller books, I made the dates more and more modern and added Elo filtering.

It takes a lot of games even to make the smaller books, because a move will not be selected unless it occurs frequently.

The smallest book took about 11 MB of PGN, for instance. There is a funny cusp that took place about 14 MB where the books rapidly shot up in size.

[chessdev]

thanks dann. i took your tiny books (the 4kb and 17kb) and put them live and they are not giving much variation.

i think what might be happening is that it's pulling only winning games, or best chances, or whatever. what i really want though is a SHALLOW book with LOTS of variation. basically, we could take the opening ECO pgn and just use that with some loose parameters and low depth.

something like:
polyglot make-book -pgn eco.pgn -bin book.bin -min-game 1 -max-ply 10

or does that not work because we need book.dat and only have these commands:

book
add - compiles book.dat from book.pgn
on - enables use of book
off - disables use of book
best - play best move from book
worst - play worst move from book
random - play any move from book
prefer (default) - choose a good move from book (Method subject to variation)

also, after reading this it seems we don't have a lot of options for deciding what goes in the book: http://www.linuxfromscratch.org/piperma ... 46597.html

pardon my ignorance, but is there no way to manually just create a book.dat and decide exactly what goes in it?

i REALLY appreciate your help!

[Dann Corbit]

thanks dann. i took your tiny books (the 4kb and 17kb) and put them live and they are not giving much variation.

i think what might be happening is that it's pulling only winning games, or best chances, or whatever. what i really want though is a SHALLOW book with LOTS of variation. basically, we could take the opening ECO pgn and just use that with some loose parameters and low depth.

something like:
polyglot make-book -pgn eco.pgn -bin book.bin -min-game 1 -max-ply 10

or does that not work because we need book.dat and only have these commands:

book
add - compiles book.dat from book.pgn
on - enables use of book
off - disables use of book
best - play best move from book
worst - play worst move from book
random - play any move from book
prefer (default) - choose a good move from book (Method subject to variation)

also, after reading this it seems we don't have a lot of options for deciding what goes in the book: http://www.linuxfromscratch.org/piperma ... 46597.html

pardon my ignorance, but is there no way to manually just create a book.dat and decide exactly what goes in it?

i REALLY appreciate your help!

It should be possible to write a program do to it. This would be quite a bother because we would have to carefully reverse engineer the current book format and understand the operation quite well before even beginning.

Another possibility is to use another book format altogether, and simply replace the book operations with the new book. Polyglot books, ctg books, etc. spring to mind. I do not know of a java reader for those particular formats, but it is not unlikely that one exists somewhere.

[chessdev]

i see. that's probably not worth the time then. hmmm.

did you use polyglot to create the tiny books, or the gnuchess "book add" ?

also, do you know how to use the "random" option? do we use that when making the book, or when starting the engine?

thanks!!