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Subject: Re: Correction, Sorry Re: Is the NPS tend to grow at the end of the game?

Author: Graham Laight

Date: 09:32:59 07/25/00

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On July 25, 2000 at 10:30:01, Ed Schröder wrote:

>On July 25, 2000 at 06:55:22, Graham Laight wrote:
>>On July 25, 2000 at 01:58:54, Ed Schröder wrote:
>>>Hash tables and NPS generally have very little in common. Lowering the
>>>hash table size will increase NPS with a few percent because less hash
>>>table code is executed.
>>If this is right, then the best thing to do is to have no hash tables whatsoever
>>- this will maximise your NPS and simplify your code!
>No hash tables will result in a speed drop of a factor 3-4 average. The
>hash table code is in the search module and not in the evaluation module.

Sorry, but I'm getting confused here. Let me try to state as simply as possible
what I think you're saying, and if it's wrong, somebody can correct me:

* hash tables are used to store positions which have already been evaluated

* sometimes, in the search, a position will come up which has already been
looked at previously

* if so, that branch of the search need not be done again, because the results
are already in the hash table

* thus, using hash tables, you'll do fewer NPS, but you'll still be better off
because you won't be wasting time searching branches that have already been


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