[computer-go] Efficiently selecting a point to play in a random playout

[Peter Drake]

On Jun 5, 2007, at 11:57 AM, Don Dailey wrote:

> But if you are taking the vacant points out it is probably not
> too biased as you say.

Yes, that's the key point -- almost all vacant points are legal.

> But what I do is pretty fast.  Always choose a random point but
> keep shrinking the list.  When a point is occupied move it out
> of the way so it's never selected again.   You have to do some
> simple bookeeping - basically swapping the position of elements
> and shrinking the list (in your terminology, maintaining a set
> of empty points.)

If I understand you correctly, I'm doing the same thing --  
maintaining the list of vacant points incrementally. Whenever there  
is a capture, I just add the captured points to the list.

Peter Drake
http://www.lclark.edu/~drake/