Re: [gnugo-devel] Pattern for seki (bug 175)

[Gunnar Farnebäck]

Joseph Piche wrote:
> I believe the semeai and owl code breaks down pretty bad with this
> pattern. It's obvious the best move for black is B2, but when white
> responds with C1, gnugo gives up. The response W-C2 B-C1 W-B3 B-A3 is
> found with default options. But when you turn the level up, W-C1 is
> found. Adding S15b S15c would help there, but W-C1 B-A3 W-B1 B-C2 and
> white has options at W-B3 B-A2 and W-A2 which black doesn't know how
> to deal with. (Of course the correct response is B-A1 W-B3 B-D1 W-C1
> B-A2.)

That's why there are many tests for followup positions in seki.tst.
Please see
http://trac.gnugo.org/gnugo/attachment/ticket/175/seki_tests_7_12.1
for a bunch of followup tests in this case. They are not very easy to
follow by hand (due to play/undo commands) but can be comfortably
viewed with view.pike.

The results don't look to bad, except for the failure to find the
response to B2-C1. Actually the semeai reading does find A3 but
find_moves_to_make_seki() in semeai.c fails to call the semeai
reading.

/Gunnar