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Subject: Re: triangular array vs. walking the hash table

Author: Stuart Cracraft

Date: 15:55:25 09/19/04

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On September 19, 2004 at 17:51:05, Michael Henderson wrote:

>On September 19, 2004 at 17:04:14, Stuart Cracraft wrote:
>
>>In my search printout, for my per-iteration pv,
>>I print out the contents of pv[0][0] .. pv[0][pvlength[0]]
>>on the first line and then right under it I print out the
>>results of walking the hash table.
>>
>>In most cases these agree. But fairly often, maybe one
>>iteration or two per search, the walk-the-hash-pv is
>>longer by a move or two than the triangular array pv.
>>
>>So a few questions:
>>
>>  1) my code blocks the backing up of the triangular array
>>     when the search has timed out. reasonable?
>
>I haven't put any abort feature in my code yet, to be honest, but I've heard you
>have to avoid putting garbage moves in your PV.

Don't start. The timed out version for not backing up triangular
array when time has timed out lost significantly in WAC.

>
>>
>>  2) is the above normal that walking the hash gives sometimes
>>     a longer pv?
>
>perfectly normal since many people use hash to "extend" their PV's
>

Not sure I understand.

>
>>
>>  3) I update my triangular array in the main search and the
>>     quiescence search. reasonable?
>
>yes.  The problem with qsearch is that it's just "cleanup"--considers only
>certain types of moves.  So qsearch section of the PV might contain some stupid
>moves you might not want to display.  There's nothing wrong with knowing what
>your qsearch is doing, though...

More information is never less, to be sure.

>
>>
>>  4) Anything else you can think of.
>
>Just wanted to say I like to answer your questions!
>
>good luck,
>Michael
>

Ha! Hey, in 10 more years I'll be 10% of the way there.



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