Many Faces uses position value collection. Positions are hashed and looked up in the position table (with a hash invariant to rotations and reflections). Each node has information about the position (wins, losses, strongest players at this position, etc). It's easy enough to do a 1 ply search to get position -> move values. It's easy to fill the table with professional positions to get a pro game collection. It's easy to map a game tree to the table. So I think this is the most general solution.
Earlier versions used a game tree since that is much easier to code. I switched to the position/value collection in version 12. David -----Original Message----- From: computer-go-boun...@computer-go.org [mailto:computer-go-boun...@computer-go.org] On Behalf Of Willemien Sent: Wednesday, June 17, 2009 4:45 AM To: computer-go@computer-go.org Subject: [computer-go] opening book structure I was puzzeling what is the best way to organise an opening book? i am writing a program to be very strong on 7x7 go program (as prelimary for writing a very strong 9x9 program ) and am wondering what is the best structure for an opening book. Where i am at the moment is: There are about 4 fundamentally different ways to structure it 1 a position -> move collection (if the position is such make that move) 2 a position value collection (this position is good, that position is bad for the colur who is on the move) 3 a professional game collection (let the program just play like the pro's) 4 a game tree (game with lots of variations) all have there advantages and disadvantages. 1 is close to what the program uses but is a long list. (difficult to maintain?) 2 same problem as 1 maybe even more extreme, but easy to use for the program 3 are reasonably easy to find. (for standard sizes Godod ed) but has many hiatus (what if my opponent doesn't play like Go Seigen) 4 is easy to use with go editors (Drago ed) but problems with transpositionings ed. I would like to hear from others what kind of opening book they use and why. and how they maintain it. and if i am missing important things. _______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/ _______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
