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

Author: Andrew Williams

Date: 05:19:12 09/09/99

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On September 08, 1999 at 18:07:13, Peter McKenzie wrote:

>On September 08, 1999 at 06:40:39, Andrew Williams wrote:
>
>>On September 07, 1999 at 19:10:37, Peter McKenzie wrote:
>>
>>>On September 07, 1999 at 13:54:40, Bruce Moreland wrote:
>>>
>>>>On September 07, 1999 at 10:27:06, James Robertson wrote:
>>>>
>>>>>On September 07, 1999 at 09:01:34, Andrew Williams wrote:
>>>>
>>>>>>Using this scheme, what would you count if you enter a search node, check for
>>>>>>extensions, find there are none and decide to go into the qsearch? One node
>>>>>>or two?
>>>>>>
>>>>>>Andrew
>>>>>
>>>>>Er.... I think that case is impossible in my program. :)
>>>>
>>>>This kind of stuff is not impossible using the generic Thompson search/qsearch
>>>>model.  You can get a case where you call qsearch, notice that you are in check,
>>>>and do "return search(...)", which would count a node for "qsearch", and another
>>>>node for the recursive call into "search", even though only one node was really
>>>>dealt with.  This of course depends upon where you put the nodes++, which isn't
>>>>present in the Thompson pseudo-code.
>>>
>>>Seems to me the simplest place to put nodes++ is in the MakeMove function.
>>
>>I can't really do that as I use my hash table for generating my PV and need
>>to use make_move to walk up and down the PV at the end of iterations. I guess
>>I could write a stripped down make_move, but I haven't really looked at that
>>yet.
>
>or:
>
>nodesCopy = nodes;
>MakePV();
>nodes = nodesCopy;
>
>or maybe the solution is worse than the problem :-)
>

Yes :-). I'm actually quite happy with the way I count nodes, I just wanted
to be sure that the number I'm getting is generally comparable with others'
figures.

BTW Congratulations on the latest version of lambchop. Seems very strong.

Andrew


>>
>>Cheers
>>
>>Andrew
>>
>>>
>>>>
>>>>I think that one node should be counted in cases like these.  If you end up
>>>>counting a lot of nodes twice, you can be comparing with someone else who has
>>>>written essentially the same program, and it looks like you are going faster.
>>>>
>>>>bruce



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