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Subject: Re: Do programmers mean to the same thing when they say nodes?

Author: Andrew Williams

Date: 12:49:43 09/06/99

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On September 06, 1999 at 14:40:00, Bas Hamstra wrote:

>On September 06, 1999 at 10:51:55, Andrew Williams wrote:
>
>>On September 06, 1999 at 10:09:57, Bas Hamstra wrote:
>>
>>>On September 06, 1999 at 07:41:01, blass uri wrote:
>>>
>>>>On September 06, 1999 at 07:05:03, blass uri wrote:
>>>>
>>>>>I know that nodes in some programs(like Junior) include illegal moves and my
>>>>>question is if the same illegal moves are defined as nodes by all the programs.
>>>>
>>>>I am not sure about the definition of nodes about Junior but I am sure that
>>>>Junior generate illegal moves and it discovers that they are illegal only by
>>>>search so I guess that it does not count only legal moves as nodes.
>>>>
>>>
>>>Another thing is: the natural way to count nodes is to put a nodes++ in the
>>>search and in the qsearh. But then you double count the leafs of the normal
>>>search (same node, same depth in search and qsearch).
>>
>>Is this the norm for programs? What PostModernist does is to increment abNodes,
>>then check if there are any extensions. If (after taking into account any
>>extensions) we're out of depth, I *decrement* abNodes and call quiesce(..),
>>which increments qNodes as its first step. Total nodes is then abNodes+qNodes,
>>and nodes are not counted twice in this scheme.
>
>I do it exactly like you. I think that is sort of the norm now. I think Crafty
>does it too. Remains the point: do you count illegal moves, or not? I do count
>them. I know some who don't.

I forgot to answer this part. Yes I do count illegal nodes.

Regards

Andrew


>>>But: does it make sense to compare NPS between programs? Suppose one program
>>>uses SEE pruning and the other program not. Now the program without SEE will
>>>have a higher NPS. But does this comparison make any sense?
>>>
>>
>>As you say, it's often comparing apples and oranges. But if we all counted
>>nodes in exactly the same way, we'd have taken one variable out of the equation
>>when comparing programs.
>
>I agree.
>
>Regards,
>
>Bas Hamstra.
>
>>
>>Andrew Williams
>>
>>
>>>
>>>
>>>Regards,
>>>Bas Hamstra.
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>>Uri
>>>>
>>>>>
>>>>>If the answer is negative then we cannot say that one program is a faster
>>>>>searcher only because it searches more nodes per second.
>>>>>
>>>>>We need a clear definition of nodes to compare.
>>>>>
>>>>>Uri



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