--- In qalam@yahoogroups.com, "Nicholas Bodley" <nbodley@...> wrote:

> On Sun, 16 Jan 2005 20:14:41 -0000, Richard Wordingham
> <richard.wordingham@...> wrote:

> > However, although it has 'invisible times' U+2062

and 'invisible

> > separator' U+2063, there is no mechanism for forming subscripts!
>
> Well, humans defined it, and they can have human weaknesses.

Nevertheless,

> I found Unicode quite inspiring when I first studied it. The song

on the

> CD in the 3.0 book is really quite lovely, btw.
>
> > The use of subscript digits in XML documents 'is discouraged'.
>
> Disgusting. Are XML and chemical formulae mutually exclusive?

I think the point is that you are supposed to use mark-up for the
numbers of atoms and the charges.

> > Unicode for Maths is discussed at

http://www.unicode.org/reports/tr25/ .

>
> Thanks!
>
> > On the other hand IF your browser/font supports it, you can

write base

> > 10 vulgar fractions to your heart's content - use fractional

slash

> > U+2044! (It failed for IE 6.0, but maybe that's because I

wasn't using

> > the right font.)

Confirmed as partly a font problem. The fractional slash displays as
a space with gentium, but as a more horizontal slash with Arial.
However 1⁄2 is not the way it should be displayed! The Unicode
standard says,

'Such a fraction should be displayed as a unit, such as ¾ or as !
[form with horizontal solidus]. The precise choice of display can
depend upon additional formatting information.

'If the displaying software is incapable of mapping the fraction to
a unit, then it can also be displayed as a simple linear sequence as
a fallback (for example, 3/4).'

Not quite sure where to pin the blame - I suppose the font would be
a good candidate. It would probably take serious effort by
Uniscribe (or its equivalent) to get arbitrary fractions laid out
nicely.

Incidentally, I was wrong about the hex entry of the character codes
not working. Philip Newton has pointed out to me that ⁢
should work, and indeed it does on my PC. I don't know why I
thought it didn't - perhaps I had tried it with the incorrect
leading 0 before.

Richard.