Re: computer-go: unmake move?

[Don Dailey <drd@xxxxxxxxxxxxxxxxxxxxx>]

> 300K nps is very good.  You must have a very simple evaluation
> function, and a very fast move sorter. 
> 
> Most of the strong go programs get less than 100 nps, since the
> evaluation is so slow and complex.  With very slow evaluations,
> unmake time is not an issue.
> 
> Many Face's tactical analyzer gets about 50,000 nps on a fast PC.
> Its time is dominated by move selection and sorting.  Evaluation
> for string tactics is trivial (just count liberties).



P.S.  And that's what amazes me.  Your program is one of the best,
      and it does about 50,000 nps, and yet other very good
      programs do only 100 nps.  My program does 300,000 nodes
      per second but stinks!   It shows the complexity of the 
      game and demonstrates that there is much room for imagination
      and varied approaches to writing a quality program.