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Subject: Re: If you like to find a mate... (corrected followup)

Author: Heiner Marxen

Date: 17:36:22 01/19/01

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On January 19, 2001 at 19:44:02, leonid wrote:

>On January 19, 2001 at 17:54:10, Heiner Marxen wrote:
>>
>>Since increasing depth seems to help me as compared to you,
>>I suspect much of it is caused by the TT.  My hit rate is not large,
>>8.6% normal hits and 18.2% hits for ETC (enhanced transposition cutoffs).
>>But with some depth left to go that can have quite an effect.
>
>Heiner, please don't use with me abreviation! I just don't know what it is TT.
>If you will write something in German, or even in Chinese - never mind! I have
>all dictionaries in my room to help me. I have no chance with abreviations. Only
>few I learned already by heart.

I am sorry!  Of course I should have explained that abbreviation, also.

TT = "transposition table", also known as "hash table".
Transposition table is the more "official" name found in books and articles,
and hash table is more often used in speech and discussions.
(That is my impression, anyhow).
Hash table is not as precise as transposition table, since a transposition
table might be implemented differently (i.e. not as a hash table...
yes, I have tried that), and hash tables can be used for other purposes than a
transposition table.


>>To measure the effect of good move ordering, I would have to replace it
>>with another one, and re-run.  I'm too lazy for this just now.
>>I suspect that you will at least also prefer check moves and captures,
>>so for this special problem we may do comparatively equal:  white has
>>left quite some pieces to be agressive in that simple way.
>>
>>BTW, here are my branching factors inside the "no mate in 8":
>>mvx  8:         87         87  [ 87.000  1.000]          1
>>mvx  7:        438        533  [  5.034  1.217]
>>mvx  6:       1713       2259  [  3.214  1.319]          1
>>mvx  5:       7444       9227  [  3.295  1.240]        154          4
>>mvx  4:      70334      74945  [  7.623  1.066]       2052          5
>>mvx  3:    1469915    1314821  [ 19.613  0.894]
>>mvx  2:   33639291   23346271  [ 25.585  0.694]
>>mvx  1:    4117503          0  [  0.176       ]
>>
>>Just implement your TT.  You will love the effect!
>
>If TT have something to do with hash table then I expect to come to this sonner
>or later. Mainly when complet rewriting for Linux will start. I dream already to
>start my new system writing! But probably I must wait up  to the end of Summer.

Yes, you guessed right, I mean the hash table.

>Today went reading about new 64 bits chip. Could never understand if this
>Intel's chip already came, or close to be produced but it give wonderful
>impression! 128 new 64 bits registers to play with. When finally it will be no
>more rumor but real chip for all of us!!!!

Although I have not done anything related to assembly or machine language
since 10 years, I still remember the good feeling to be able to play with
just every bit that is there, and to control just every nanosecond ;-)

Sorry again, Leonid, and have a nice day!

Heiner



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