[XeTeX] Roman Numerals as stylistic alternatives

[enrico.gregorio at univr.it]

Tobias Schoel wrote:

> Roman Numerals derive from a alphabetic writing system and thus are 
> "words" consisting of single "letters" with a meaning based on its 
> identity and position.

The Roman system is definitely not alphabetic, but simply additive
like the Egyptian system. It was based on 5 instead than on 10, and it
consists in repeating a symbol until we get to a number for which another
symbol exists: I II III IIII V. The subtraction rule came later; one of the
motivations was to save space in inscriptions: XC is much better than
LXXXX in this respect. The rules as we use them now were fixed in
the Middle Ages.

Being non alphabetic, each symbol has different values, depending on
the context. This is very different from the Ionian system, where alpha
is 1, beta is 2 and so on; iota is 20, kappa is 30, and so on.

The original form of the Roman "digits" evolved from the Etruscan shape
until they became identical to some letters. For example, the digit for
1000 was a circle divided into quarters. 

I'll think to a way for adding the /ActualText to the macros I showed you.

Ciao
Enrico

--
Enrico Gregorio          + Dipartimento di Informatica          + Tel: +39 045 8027937
Enrico.Gregorio at univr.it + Università degli Studi di Verona     +
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