On Wed, 15 Jun 2005, Gunnar wrote: > Testcase semeai:120, > > # A14 is strictly correct since C19 allows W an unfavorable ko. > loadsgf games/semeai/semeai19.sgf > 120 analyze_semeai C18 C19 > #? [1 1 (A14|C19)]* > > is broken. The most immediate problem is that the proposed move at C19 > is already occupied. Second there's no way to win the semeai (though > seki is possible). Finally the semeai ought to be C18 vs C17, not C18 > vs C19.
I don't think Black can even achieve seki: A B C D E F G H J K L M N O P Q R S T 19 . X O . . . O O . . . . . . . . . . . 19 18 O O X X X X X X O X X . O O . O O X . 18 17 . X O X O O O O O . . O . X O O X . . 17 16 O . O X X O X . . X X O X X X X X . . 16 15 . O O O O X X O O O O X O . . . . . . 15 14 . X O X X X . . . . O X . . . . O . . 14 13 . X X . . . . . . . . X O . . . . . . 13 12 . . . . . . . . . X . . X . . O . . . 12 B A14, W A17, B a15, W b16 Now if B d19, just white f19 wins. If B f19, W D19, B J19, W H19 reaching: A B C D E F G H J K L M N O P Q R S T 19 . X O O . X . O X . . . . . . . . . . 19 18 O O X X X X X X O X X . O O . O O X . 18 17 O . O X O O O O O . . O . X O O X . . 17 16 O O O X X O X . . X X O X X X X X . . 16 15 X O O O O X X O O O O X O . . . . . . 15 14 X X O X X X . . . . O X . . . . O . . 14 13 . X X . . . . . . . . X O . . . . . . 13 12 . . . . . . . . . X . . X . . O . . . 12 And it is still one eye against no eye, and black cannot approach white fast enough.. > I suspect that the test should be for an earlier position. Dan, do you > remember how this was intended? > > /Gunnar Hence I suggest the patch below. Arend Index: semeai.tst =================================================================== RCS file: /cvsroot/gnugo/gnugo/regression/semeai.tst,v retrieving revision 1.69 diff -u -p -r1.69 semeai.tst --- semeai.tst 13 Apr 2005 21:19:02 -0000 1.69 +++ semeai.tst 3 Sep 2005 15:10:38 -0000 @@ -439,8 +439,8 @@ play white H2 # A14 is strictly correct since C19 allows W an unfavorable ko. loadsgf games/semeai/semeai19.sgf -120 analyze_semeai C18 C19 -#? [1 1 (A14|C19)]* +120 analyze_semeai C18 C17 +#? [0 0 PASS] # There is a complication that B18 and C17 are not amalgamated. # If B plays first C19 gives a favorable ko; A15 allows seki. _______________________________________________ gnugo-devel mailing list [email protected] http://lists.gnu.org/mailman/listinfo/gnugo-devel
