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Subject: Re: retrieving the PV from hash questions

Author: Stuart Cracraft

Date: 20:56:26 09/07/04

Go up one level in this thread


On September 06, 2004 at 22:41:32, Robert Hyatt wrote:

>On September 06, 2004 at 22:05:58, Stuart Cracraft wrote:
>
>>On September 06, 2004 at 18:33:47, Robert Hyatt wrote:
>>
>>>On September 06, 2004 at 04:47:12, Alessandro Scotti wrote:
>>>
>>>>On September 05, 2004 at 22:12:35, Stuart Cracraft wrote:
>>>>
>>>>>I walk the PV until there is no further position. No limit. This can then
>>>>>either be left in the hash table if you don't clear between searches
>>>>>but like Bob, you should keep the PV entries and restore them in the
>>>>>hash table before the next search whether or not you table-clear due to
>>>>>potential changes.
>>>>>
>>>>>I don't do this. It's a simple fix. I don't know why I've delayed putting
>>>>>it in.
>>>>
>>>>I don't either. But since I get my PV from the hash table, it's already there.
>>>
>>>
>>>It won't _always_ be there .  That is the problem.  You can overwrite a key
>>>position and lose a move in the PV, and hence the _rest_ of the PV will not be
>>>useful.
>>
>>I understand that. But unless you record the PV with an alternate technique,
>>you can't fill it since source == destination.
>
>I was assuming a non-flawed method of maintaining the PV.  :)
>
>
>
>>
>>And I am not sure I want to do the triangular array gubbish.
>
>
>That's _the_ answer to do it right, however.  And it is trivial to do.

The method I saw at Bruce's webpage doesn't look great to me.



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