Re: transposition table

["Serge Boisse STNA 7P (33) 562 14 5731" <boisse@xxxxxxxxxxxx>]

Darren Cook wrote:

> >> This works fine as long as  (super) Ko is not relevant for the position, (I
> >> notice a great speed improvement), but  when Ko or super Ko is relevant,
> there
>
> > Since there are very few symmetric positions in a real GO game (after
> >the first 4 or so moves)
> >I do not consider board symmettries.
>
> That was my reaction, but if I understood Serge correctly the speed
> improvement mentioned above came after adding board symmetries. ?
>
> I use the board symmetries in a pattern database, but then I ignore ko
> completely (and let search based on the patterns discover illegal moves).
>
> Darren

Well, in fact, symetries give speed inprovement on small boards (up to 5x5) , but
not much more for bigger ones.(but "classical" transposition table helps for any
size).
But I like the beauty of it...

Thank you, Darren and Paul, for your fast reply. The idea of adding a Ko term to
the hashcode is a good one.
I'll try that.


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