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Subject: Re: Status of Brutus?

Author: Robert Hyatt

Date: 10:20:34 07/30/03

Go up one level in this thread


On July 30, 2003 at 00:23:02, Keith Evans wrote:

>On July 30, 2003 at 00:13:08, Robert Hyatt wrote:
>
>>On July 29, 2003 at 23:54:19, Keith Evans wrote:
>>
>>>On July 29, 2003 at 23:27:03, Robert Hyatt wrote:
>>>
>>>>On July 29, 2003 at 00:54:39, Keith Evans wrote:
>>>>
>>>>>On July 29, 2003 at 00:31:17, Robert Hyatt wrote:
>>>>>
>>>>>>On July 28, 2003 at 20:59:24, Vincent Diepeveen wrote:
>>>>>>>It is like comparing a sniper rifle from 2003 with a sniper rifle from world war
>>>>>>>1.
>>>>>>>
>>>>>>>Distances they shot at in world war 1 and 2 with sniper rifles must have been a
>>>>>>>few hundreds of meters.
>>>>>>
>>>>>>In WW1 my grandfather was a sniper.  He shot at ranges up to 1000 yards.
>>>>>>
>>>>>>In WW2 my father was a sniper.  He shot at ranges up to 1000 yards.
>>>>>>
>>>>>>Today, a neighbor down the street is a sniper.  He shoots at ranges up to 1000
>>>>>>yards.
>>>>>>
>>>>>>_nobody_ shoots a sniper rifle at ranges of "kilometers" today.  "kilometer"
>>>>>>perhaps.  With an occasional attempt at up to 2km with a big 50 cal "rifle".
>>>>>>
>>>>>
>>>>>Supposedly Gunnery Sergeant Hathcock took out an NVA at 2500 yards with a .50
>>>>>caliber machine gun. A friend got into the whole "Marine Sniper" scene and it
>>>>>was a little scary. Nice skill to have if you need it, but it scares me when
>>>>>people fantasize about it. (Especially when the word "safety" is spelled
>>>>>incorrectly at the range ;-)
>>>>
>>>>
>>>>2500 yards is how many kilometers?
>>>>
>>>>:)
>>>
>>>Exactly why I mentioned this story...
>>>
>>>x [km] = 2500 [yards] * 0.91 [m/yard] = 2275 [m] or 2.275 [kilometers]
>>>
>>>Is the story true, that I don't no. Trivial to do - definitely not. Something
>>>that you would sling over your shoulder, etcetera.
>>>
>>>>
>>>>As I said, 1000 yards is a _long_ shot today.  2500 yards is way beyond
>>>>luck unless there is _zero_ win, _zero_ mirage caused by heat, _zero_ movement
>>>>of the target, etc.
>>>>
>>>>I doubt _any_ sniper would take the challenge of "you shoot at me at 2500 yards
>>>>first, then I shoot at you from 1000 yards.  we continue until one of us is
>>>>dead."
>>>>
>>>>
>>>>>
>>>>>>This is just another area where you know nothing, but write as though you are
>>>>>>an expert.
>>>>>>
>>>>>>BTW, Hsu's move generator is _not_ a lot better than Belle.  All you have to
>>>>>>do is read his paper to see what he did...
>>>>>
>>>>>Hsu did add some modes which Belle did not have. For example finding checking,
>>>>>check evasion, and attacking moves. He hints at some other things like
>>>>>generating moves for pruning but this is very vague. He may have handled those
>>>>>basic special case moves (castling, ep captures) more elegantly, but it's hard
>>>>>to tell without seeing the implementation details of each. Hsu also added
>>>>>hardware repetition detection which is not part of the basic move generator
>>>>>logic, but if you group it with movegen just for the sake of argument then it's
>>>>>a noteworthy improvement. Maybe the adjective that Vincent used was a little
>>>>>extreme, but this statement doesn't bother me too much.
>>>>>
>>>>>-K
>>>>
>>>>
>>>>Yes.  But the base move generator was belle without the disable stack.  Omitting
>>>>the disable stack was the key thing to make it easier to put belle on a chip
>>>>in 1986 hardware fabrication at MOSIS.
>>>
>>>Could Belle generate check evasion moves directly? If Hsu's design can and Belle
>>>could not, then doesn't it follow that Hsu's design is better?
>>
>>Let's define "Move generator is better".
>>
>>I was quibbling with the concept of "it was much better".  I don't think it
>>was.  Belle didn't generate "escape from checks" not because he couldn't, but
>>because he didn't see the need with his particular original software approach.
>>
>>Hsu's is better due to the missing "disable stack".  But how much better?  IE
>>it still operates at the same relative number of clocks as Belle, so it is no
>>faster.  It is just a smaller circuit which let him _barely_ fit it onto a
>>single chip at MOSIS.  DB and particularly DB2 were not "smaller" at all.
>>
>>I might use the term "more flexible" as opposed to "significantly better."
>>
>>Or "a little better".
>
>We're basically in agreement here. Hsu did make some clever improvements which
>should not be forgotten - how much they contributed to the strength of Deep Blue
>will probably never be known. After reading his book, it seems like he wouldn't
>have had enough time to experiement with all of the new features in DB2. Maybe
>some of the "improvements" were not used in the match?


Clearly he said that most of the new evaluation stuff was not used.  There
wasn't enough time.  I'm not sure if "most" == 50% or what, however...

It was a beast, regardless of Vincent, however.

At least I personally got to play its predecessor with my program that was
not a "pushover".



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