Extensive test series on tweaking history limit and bonus
formula. At the end this was the best.
After 11959 games:
Mod vs Orig 2087 - 1934 - 7938 ELO +4 (+- 3.7) LOS 92%
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Respin this old idea. Earlier we tried only
with < 1000 games and result was inconclusive.
After 5845 games
Mod vs Orig: 935 - 936 - 3974 ELO (+-3.6)
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Also renamed history access value in something more
in line with the meaning.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Instead of piece-from-to, in this way it is similar
to what we already do for history.
Almost no change, but seems a bit simpler in this way.
After 995 games at 1+0
Mod vs Orig +207 =596 -192 +5 ELO
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This will be useful to use gains table in move
ordering along with history table.
No functional change and big code remove.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
After history accounting rewrite in 1.6, a small
tweak of history parameters seems positive.
Note that these are not to be considered the optimal
values, just a wild guess that proved good.
Finding the optimal values would require a much longer
testing time.
After 967 games at 1+0
Mod vs Orig 240 529 198 +15 ELO
Functionality Signature: 21222553
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Instead decrement history value on failure.
After 999 games at 1+0
Mod vs Orig +236 =558 -204 51.60% +11 ELO
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Both with added comment and changing the API to
reflect that only destination square and moved piece
is important for history.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
