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Unicode mathematical control characters

Is it allowable to submit math control characters to Unicode? After all,
Unicode has added new control characters such as line and paragraph
separators.

If one has a few math control characters, then a wide variety of math
symbols could be assembled by intelligent renderers; simpler programs could
display a default symbol instead for each control character it does not
know how to handle.

Suppose one has the following control characters
            above
    presup ______ sup
          |      |
   before | over | after
          |______|
    presub  below  sub
for the positioning of a new symbol relative an old symbol, plus "logical
left parenthesis", "logical right parenthesis", "mathematical horizontal
tab", and "mathematical vertical tab".

Then these many common math symbols can be constructed, plus such things as
chemical symbols and such.

I can give some examples how this might work: Name the symbols
    00    presup
    01    above
    02    sup
    10    before
    11    over
    12    after
    20    presub
    21    below
    22    sub
    30    logical left parenthesis
    31    logical right parenthesis
    32    mathematical horizontal tab
    33    mathematical vertical tab

Then for example, a matrix
    ( x y
      u v )
could be described as
    ( x #32 y #33 u #32 v )

A summation sign "Sum" with the expression "n = 1" below could be described as
    Sum #21 #30 n = 1 #31

The isotope 14 of carbon could be written
    14
      C
could described as
    C #00 14
and so on.

This the does not preempt developments such as MathML and OpenMath, as one
still is only on the level of describing the logical relation between
mathematical characters, and not full-fledged symbols.

This is basically what is needed if one should be able to express simple
mathematical expressions in a letter of type Unicode text.

  Hans Aberg
                  * Email: Hans Aberg <mailto:haberg@member.ams.org>
                  * Home Page: <http://www.matematik.su.se/~haberg/>
                  * AMS member listing: <http://www.ams.org/cml/>