While bigger examples exist, 4 in a line (with both ends enclosed) is not nakade because the two center points are miai (b and c in your example). It requires two moves (both b and c) to reduce your example to a single eye. Because of that, it is not nakade.
A comprehensive list of nakade shapes (with a complete border and no enemy stones inside the eye to start with) is given at http://senseis.xmp.net/?UnsettledEyeshapes The marked black stones are the vital point that is the one move needed to make or prevent two eyes. Larger nakade shapes usually involve systematic reduction of eyes to ever smaller nakade shapes until a final settled dead position is reached. Filling of nakade can be very order specific and a successful kill that requires a very long sequence of stones can easily be messed up in random play. On Jan 30, 2008 3:02 PM, Don Dailey <[EMAIL PROTECTED]> wrote: > According to Sensei's Library, nakade is: > > > > It refers to a situation in which a group has a single large > internal, enclosed space that can be made into two eyes by the right > move--or prevented from doing so by an enemy move. > > Several examples are shown that where there are exactly 3 points. My > example shows 4 empty points in a big eye but they have even bigger > examples. > > So I think this is nakade. > > - Don > > > Jason House wrote: > > > > > > On Jan 30, 2008 2:48 PM, Don Dailey <[EMAIL PROTECTED] > > <mailto:[EMAIL PROTECTED]>> wrote: > > > > So are you saying that if mogo had this position: > > > > | # # # # # # > > | O O O O O # > > | + + + + O # > > a b c d e > > > > That mogo would not know to move to nakade point c1 with either > color? > > > > > > That's not nakade... Even if it was one shorter, I'd expect nearly > > all MC bots to get it right. I think the problems come with big eyes > > and throw-ins. Big eyes require many moves to be correctly played for > > a kill. I can easily imagine a playout policy (expecially with > > avoiding self-atari plays) that fails to read a big eye nakade > correctly. > > > > > > > > > > > > - Don > > > > > > > > > > ------------------------------------------------------------------------ > > > > > > _______________________________________________ > > > computer-go mailing list > > > computer-go@computer-go.org <mailto:computer-go@computer-go.org> > > > http://www.computer-go.org/mailman/listinfo/computer-go/ > > _______________________________________________ > > computer-go mailing list > > computer-go@computer-go.org <mailto: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/ >
_______________________________________________ computer-go mailing list computer-go@computer-go.org http://www.computer-go.org/mailman/listinfo/computer-go/
