Re: Superscript and Subscript Characters in General Use

On Wed, 11 Jan 2017 08:32:12 +0000, Richard Wordingham wrote:
>
> On Wed, 11 Jan 2017 07:00:52 +0100 (CET)
> Marcel Schneider wrote:
>
> > The phenomenon isnʼt actually limited to plain text environments. See:
> >
> > http://stackoverflow.com/questions/13878772/how-to-display-classic-fractions-in-css-javascript
> > | You can also use the straight unicode approach to render ¹⁹⁄₄₅:
> > |
> > | ¹⁹⁄₄₅
> > |
> > | (See the wikipedia article.)
> > https://en.wikipedia.org/wiki/Unicode_subscripts_and_superscripts
>
> If you follow the link from that page to
> https://en.wikipedia.org/wiki/Subscript_and_superscript , you will
> notice an immediate issue with the position of the subscripts. This is
> why the use of explicitly coded subscript and superscript digits for
> vulgar fractions is not recommended. Rather, one needs to hope that
> the font one is using supports U+2044 FRACTION SLASH. As not all fonts
> support all superscript and subscript digits, text using them may
> render badly, whereas U+2044 itself will usually be rendered at least
> tolerably even if the glyph comes from a different font to the digits.
>
> The truly straight Unicode approach in HTML is to use 19⁄45.
> Just entering those 5 characters into a text entry box in Firefox gave
> me a properly formatted vulgar fraction. That is how vulgar fractions
> are supposed to work. Unfortunately, one may need to avoid 'exciting
> new fonts' in favour of those with a large, working repertoire.

Thank you for these hints! Too bad not to have checked this. Iʼm glad to see
that browsers and some fonts already support the standard way of writing
custom fractions in plain text, with correct glyph substitution.
Iʼve added this info on the fly to the following two articles:

https://en.wikipedia.org/wiki/Unicode_subscripts_and_superscripts#Uses
https://en.wikipedia.org/wiki/Slash_(punctuation)#Fractions

Hence, one part of the issue is solved.

As of the main part – the use of modifier letters as ordinal indicators, and
eventually in (other) abbreviations –, the user demand reflects in the article
that you cited: For Galician, Italian, Portuguese and Spanish, the preformatted
ordinal indicators are used, while for French, formatting is applied:
https://en.wikipedia.org/wiki/Subscript_and_superscript#Unicode
If this use of formatting were straightforward, it would be constant. In practice,
by contrast, it turns out to be actually a fallback, by (supposed) lack of the
appropriate preformatted letters.

I note too, that the used fonts from the body font stack is outdated since it
doesnʼt render the fractions properly (whereas the monospaced font in the editing
dialog does, as in the Unicode contact form that Iʼve tried first). A frequent
idea is then to use performatted digits to imitate proper rendering, as more as
according to Wikipedia, this is so popular that current fonts have even repurposed
the super/sub scripts. Arial Unicode MS would thus enter this category. As you point
it out, the straightforward action is to use a font with full support of U+2044,
and thus to override the default font with e.g. Cambria.

Itʼs good to know about these issues, and this will help me a lot when writing up
the documentation.

Best regards,

Marcel
Received on Wed Jan 11 2017 - 08:20:56 CST