There was computer go before this list :) I heard this idea from Mark sometime around 1988.
David > -----Original Message----- > From: computer-go-boun...@computer-go.org [mailto:computer-go- > boun...@computer-go.org] On Behalf Of Carter Cheng > Sent: Monday, July 13, 2009 10:27 AM > To: computer-go > Subject: Re: [computer-go] Basic question concerning the edges of the board > > > Thanks all for the replies. I am not sure I quite get the 20x21+2 idea but > I will take a look back in the archives. Does anyone remember roughly when > it was posted to the list? > > Thanks again, > > Carter. > > --- On Mon, 7/13/09, Peter Drake <dr...@lclark.edu> wrote: > > > From: Peter Drake <dr...@lclark.edu> > > Subject: Re: [computer-go] Basic question concerning the edges of the > board > > To: "computer-go" <computer-go@computer-go.org> > > Date: Monday, July 13, 2009, 9:08 AM > > As in LibEGO, if you define the > > off-board points to be both black AND white, finding > > captures requires fewer branches. > > Peter Drakehttp://www.lclark.edu/~drake/ > > > > > > On Jul 13, 2009, at 8:48 AM, David Fotland > > wrote: > > I use one dimensional arrays for speed (to > > avoid a multiply by 21). > > > > Old Many Faces code uses arrays of 363 (361 points, pass, > > and null-point). > > The smallest possible arrays were required to run under 500 > > KB total memory. > > I avoided edge checks by having a set of small offset > > arrays (with 2, 3, or > > 4 offsets), chosen by the board. > > > > My MCTS code uses single dimension arrays with size > > suggested by Mark Boon, > > from Goliath, 20 * 21 + 2. This is enough to have > > points off the edge on > > all sides and diagonals. > > > > David > > > > -----Original Message----- > > From: > > computer-go-boun...@computer-go.org [mailto:computer-go- > > boun...@computer-go.org] > > On Behalf Of Carter Cheng > > Sent: Monday, July 13, > > 2009 8:36 AM > > To: computer-go@computer-go.org > > Subject: [computer-go] > > Basic question concerning the edges of the board > > > > > > Hi, > > > > I have again been > > considering trying my hand at implementing a simple go > > program. The question > > I have pertains to checking for the edge of the > > board > > in capture situations and so on. > > For a modern CPU (given what limited > > information I have on > > this) the extra branches might result in pipeline > > stalls if I am > > constantly checking if values are in range. Is it best to > > extend the size of the > > board to say 21x21 to somehow avoid these sorts of > > checks? Or are the > > relative cost of these branches negligible in the > > scheme > > of things? > > > > Thanks in advance, > > > > Carter. > > > > > > > > _______________________________________________ > > 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/ > > > > > > -----Inline Attachment Follows----- > > > > _______________________________________________ > > 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/ _______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
