[gnugo-devel] Patch: improve separation of similarly-valued moves

[Inge Wallin]

Here is a very simple patch that improves the value separation of moves
suggested by Joseki patterns.  The original code used the computed value
for a move to add a small bonus to the min value suggested by patterns.
But it only did this for non-joseki moves.  This patch removes that
limitation.

I don't know the original thought behind the limitation, but the engine
seems to have gotten good enough to understand the reason behind the
joseki moves that it is no longer neeeded.

Breakage:
./regress.sh . arion.tst
1 unexpected PASS!
./regress.sh . trevorc.tst
1180 unexpected PASS!
./regress.sh . nngs4.tst
485 unexpected PASS!

Summary: 3 PASSes, 0 FAILs

The test I was aiming at was arion:1, and it solves that one properly.  I
haven't analyzed the other ones.

        -Inge


Index: engine/value_moves.c
===================================================================
RCS file: /cvsroot/gnugo/gnugo/engine/value_moves.c,v
retrieving revision 1.121
diff -u -r1.121 value_moves.c
--- engine/value_moves.c        12 Apr 2004 15:22:44 -0000      1.121
+++ engine/value_moves.c        14 Apr 2004 20:57:51 -0000
@@ -2867,12 +2867,9 @@
     move[pos].max_value = move[pos].min_value;

   /* If several moves have an identical minimum value, then GNU Go uses the
-   * following secondary criterion (unless min_value and max_value agree, and
-   * unless min_value is bigger than 25, in which case it probably comes from
-   * a J or U pattern):
+   * following secondary criterion (unless min_value and max_value agree):
    */
-  if (move[pos].min_value < 25)
-    move[pos].min_value += tot_value / 200;
+  move[pos].min_value += tot_value / 200;
   if (tot_value < move[pos].min_value
       && move[pos].min_value > 0) {
     tot_value = move[pos].min_value;




Inge Wallin               | Thus spake the master programmer:               |
                          |      "After three days without programming,     |
address@hidden       |       life becomes meaningless."                |
                          | Geoffrey James: The Tao of Programming.         |