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Subject: Re: Shortening Huffman coding + OT

Author: Dann Corbit

Date: 13:11:00 10/29/99

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On October 29, 1999 at 16:00:55, Guido wrote:
>Huffman coding for recording a chess position, should be as follows:
>
>Empty square: 0
>Pawn: 10C
>Bishop: 1100C
>Knight: 1101C
>Rook: 1110C
>Queen: 11110C
>King: 11111C
>
>where C indicates the colour bit (0 = White, 1 = Black).
>
>For the starting chess position we have a total size of  32*1 + 16*3 + 4*5 + 4*5
>+ 4*5 + 2*6 + 2*6  = 164 bits with additional bits (from 1 to 8 IMO) for side to
>move, castle status and en passant capture.
>
>But Pawns cannot occupy the first and the last row, so only for these rows, the
>coding can be modified eliminating the first  '1':
>
>Empty square: 0
>Bishop: 100C
>Knight: 101C
>Rook: 110C
>Queen: 1110C
>King: 1111C
>
>In the best case of starting position it is possible to save 16 bits, for a
>total of 148 bits vs 164 bits of  the original Huffman coding. In a generic
>situation the saving is less and equal to the number of pieces in the first and
>in the last row.
>
>Is this reduction already known?
That is a clever idea which has been discussed before here (but I have not seen
it quite so clearly defined.)  It might be interesting to try arithmetic
compression rather than huffman coding.

>OT Argument
>
>In a past thread the problem of the language to use in CCC was discussed, as
>many people are not of english mother tongue and have problem with english. I'm
>italian and probably I speak and write english very badly.
>I don't suggest to use latin or esperanto, but more concretely that all the
>english mother tongue persons who write to CCC make an effort to use the easiest
>words and expressions they know, so more non-english people can understand and
>learn english as well as chess.
I do not think it is off topic.  Discussion of topicality and how to communicate
clearly is a Usenet tradition in any news group.  Otherwise, how can we ever
know if our discussion is suitable?  Therefore, I think your excellent
suggestion is right on target.  Knowing what words may cause difficulty is
another issue that may be difficult to meet exactly.  But thinking about it, we
may be able to reduce confusion by better choice of words.



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