For any TEIers who might want a mathematical diversion...
I would like to record the dates of a collection of manuscripts, some of
which are BC and others of which are AD. Is there any good way to
express BC and AD dates that lends itself to computer processing? ISO
8601 is great for AD dates. Unfortunately, problems occur if I want to
use the same scheme with BC dates. Prefixing a negation sign doesn't work.
E.g. Here is a list of dates in order:
If I sort these (using 'sort' on my Linux machine), I get:
If I want to work out the difference between two AD dates, I can drop
the dashes and subtract to get a good answer:
00020101 - 00010101 = 00010000
00010131 - 00010101 = 00000030
However, this doesn't work for a mixture of BC and AD dates:
00010101 - -00010101 = 00020202
The only thing I can think of is to choose some large negative date
(4004 BC?), and count everything from there.