Re: [computer-go] Ko and transposition tables

[Chris Fant <chrisfant@xxxxxxxxx>]

One option is to XOR all previous-board Zobrist hashes and store that
value in the table as well.  This would take care of #1 and #2 below.

On 5/10/05, Peter Drake <drake@xxxxxxxxxxxxxxxxx> wrote:
> I'd like to add a transposition table to my tactical searcher.  Two
> problems spring to mind:
> 
> 1) If a position is re-encountered at a shallower search depth, the
> cached value should not be used.  This is easily remedied by
> maintaining a depth for each cached value.
> 
> 2) Because of ko, it matters how a particular position was reached.
> I could deal with this by keeping track of the path to each position,
> but this would make the transposition table almost worthless.  What
> is standard practice here?
> 
> I thought I'd seen a paper on this topic, but I can't find it in the
> Online Computer Go Bibliography.
> 
> Peter Drake
> Assistant Professor of Computer Science
> Lewis & Clark College
> http://www.lclark.edu/~drake/
> 
> _______________________________________________
> computer-go mailing list
> computer-go@xxxxxxxxxxxxxxxxx
> http://www.computer-go.org/mailman/listinfo/computer-go/
>
_______________________________________________
computer-go mailing list
computer-go@xxxxxxxxxxxxxxxxx
http://www.computer-go.org/mailman/listinfo/computer-go/