Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Nodes per second

Author: Don Dailey

Date: 08:44:20 06/24/98

Go up one level in this thread


On June 24, 1998 at 09:47:15, Robert Hyatt wrote:

>On June 24, 1998 at 04:08:23, Inmann Werner wrote:
>
>>What are nodes per second.
>>I count, how often alpha-beta is called in a search, and taht are my nodes.
>>Is this correct, or should I count the generated moves?
>>It is not really important, but everybody speaks about, how many nps a program
>>makes, and if everybody defines nodes different, all compares a nonsense.
>>On the other hand, nps only give sense, if there is no computer thinking on
>>opponents time!?
>>
>>Werner
>
>
>
>that's what most of us are doing...  and your count should be
>comparable to ours... just add nodes++; to the top of search()
>and quiesce();

Technically (or sematically) this is correct, but you need to
be careful.   I count how many moves
are actually executed in a search (or in my program calls to
make_move().    I think this is more accurate.

Depending on how your program is structured counting calls to
alpha-beta could give you the wrong answer.   An early program
of mine would sometimes do a static evaluation without making
this final call, using your method would have seriously deflated
the node counts.

Really though this is an issue of semantics.  But a node is a
new position visited and not an issue of how you structure
your recursion.   I would guess that by far most programs this
would work the same.

- Don



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.