Re: [gnugo-devel] Bug maybe related patterns

[Gunnar Farnebäck]

易野 <address@hidden> wrote:
> In attached game record, GNUGO take white. After Black's move #17, #31,
> White failed reply the position of #35 and #37.

So the problem is that when black plays R7 here,

. . . . + . . . 10
. . . . . . . . 9
. . . . . . . . 8
. . . . . X . . 7
. . . . O O . . 6
. . . . . X . . 5
. . . . X . . . 4
. . . . . . . . 3
. . . . . . . . 2
. . . . . . . . 1
M N O P Q R S T

GNU Go doesn't appreciate the value of separating black at S6.

> That maybe come from an incorrect pathern match.

Rather there's a missing pattern.

Below is a patch adding a testcase for this problem and a pattern
solving it. Someone stronger may suggest a more precise test.

This problem is also documented at http://trac.gnugo.org/gnugo/ticket/69.

/Gunnar

Index: patterns/patterns.db
===================================================================
RCS file: /cvsroot/gnugo/gnugo/patterns/patterns.db,v
retrieving revision 1.139
diff -u -r1.139 patterns.db
--- patterns/patterns.db        12 Jun 2005 09:34:15 -0000      1.139
+++ patterns/patterns.db        22 Jan 2006 22:46:54 -0000
@@ -11001,6 +11001,20 @@
 ; weak(A)
 
 
+Pattern ED100
+# gf New pattern. (3.7.8)
+
+.....      cut through to weaken
+X.O..
+.XOX.
+..*..
+.....
+-----
+
+:8,OXae
+
+
+
 #####################################################################
 #
 # Center defend/attack patterns
Index: regression/strategy5.tst
===================================================================
RCS file: /cvsroot/gnugo/gnugo/regression/strategy5.tst,v
retrieving revision 1.49
diff -u -r1.49 strategy5.tst
--- regression/strategy5.tst    31 Oct 2005 23:40:32 -0000      1.49
+++ regression/strategy5.tst    22 Jan 2006 22:46:54 -0000
@@ -175,6 +175,10 @@
 293 reg_genmove white
 #? [F17]*
 
+# Very important to separate black.
+loadsgf games/tso_igobot_2006-01-16.sgf 18
+294 restricted_genmove white O6 S6
+#? [S6]
 
 ############ End of Tests #################