Emanuele Cisbani wrote: > Work has begun. > > I posted the first set of 26 tests "ported" to GNU Go, > and the problem suite folder to put in games directory. > > http://trac.gnugo.org/gnugo/ticket/41 > > Summary: 17/26 passes. 0 unexpected passes, 9 unexpected failures > > Only one failure is a misunderstanding of semeai problem > (GNU Go fail to read a simple seki solution).
The failure is a very simple semeai with no eyes, two common liberties and three (white) vs two (black) outer liberties. This is a typical case where the lack of semeai understanding in the tactical reading fools up the analysis. Since black has only four liberties a tactical attack is found, but not the tactical defense which requires filling in an outer liberty of the adjacent five liberty string. Fixing this in the tactical reading is not very difficult but doing it efficiently is. Maybe it's possible to solve it in the dragon amalgamation instead by making it more suspicious about tactically dead four liberty strings. Actually it's quite easy to disable amalgamation over four-liberty strings altogether, see the appended patch. It does solve this semeai mistake as well as testcases semeai:48 and semeai:147. Probably it does bad things elsewhere though. /Gunnar Index: patterns/conn.db =================================================================== --- patterns/conn.db (revision 2407) +++ patterns/conn.db (working copy) @@ -629,7 +629,8 @@ Bc dA -;(attack(A) || attack(B)) && !disconnect_helper(c,d) +;((attack(A) && lib(A) < 4) || (attack(B) && lib(B) < 4)) +;&& !disconnect_helper(c,d) Pattern CC506 _______________________________________________ gnugo-devel mailing list gnugo-devel@gnu.org http://lists.gnu.org/mailman/listinfo/gnugo-devel
