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Subject: Re: Major Breakthrough on the 20 Byte Problem!!!

Author: Ricardo Gibert

Date: 07:18:53 08/20/99

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On August 20, 1999 at 00:59:51, KarinsDad wrote:

>On August 19, 1999 at 23:01:19, Ricardo Gibert wrote:
>
>[snip]
>
>>Presumably, with 17 cases, you would in effect be dividing up one database into
>>17 databases. Which one you look in is determined by the search key. Example:
>>The position I am looking for has 4 pawns so I look in database 4 + 1 = 5th
>>database.
>>
>>Karinsdad is gradually getting more aggressive with this technique to achieve a
>>more compact form, but he is not really encoding positions in fewer bits,
>>whether it 160 bits or or 128 bits or whatever, since you must not forget the
>>bits encoded "by location".
>>
>>At first it seems you are getting something for nothing, but you are really
>>making a trade off at the expense of simplicity, time and flexibility. You must
>>manage more cases. 2^180 cases is an example of over doing it. Inefficiencies
>>can develope when you divide up the "cases" in a way such that only a few are
>>being used most of the time and the other cases use up time and space for little
>>return. The trick is how to divide things up. The dividing up into cases is a
>>kind of sort, which is preserved by the database itself to save spacein its
>>storing of values.
>
>I think you misunderstand. Although I have 351 cases, I am using a series of
>algorithms based on the data. The data determines which case it is in. There are
>no inefficiences since each case uses the portions of the algorithms that it
>needs, but not at the expense of any other case. It does not matter if you used
>it for a database of promotions or a database with no promotions or no database
>at all and just used it for one position.
>
>There is no case 1 stored at this location in a database since there is no
>database. Case 1 is determined via the structure and the data contained within
>that structure. From the algorithm's point of view, there is no case 1. Cases 1
>to 351 are merely the way I broke it down in an Excel spreadsheet to prove that
>I didn't miss any possibilities. That's all. It's not as if a program written to
>do this would have a 351 element Select statement within it.
>
>Additionally, my algorithms are not that much more complex than the standard 24
>byte algorithms such as the ones used in EPD (at least programatically). From a
>computer's point of view, my algorithms would only take a slightly greater
>amount of time to decode the position than decoding a random 24 byte position
>stored in EPD. Why? Because the majority of the bits have a one to one
>correspondence to some "real" element of the position (such as where pieces are
>located or what color a given piece is) and only a few bits are actually used to
>do "encoding tricks".
>
>KarinsDad :)
>
>PS. I really think however that I have come close to the limit (using this type
>of technique). There is only so much crap that can be fit into a 5 pound bag.

You're right, I misunderstand completely. Your description is too vague and I
guess I'll just have to wait until you've worked it out entirely.



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