[ISO8601] Re: Digest Number 61. [Was: Re: How to represent BC (BCE) - Day name.]
- On 2000-Dec-12 Bob Neifert wrote(>):
> ...... the standard only covers numericalI should have been more clear in my original message, I
> abbreviation. If you want to spell out Monday or Mon or Mo,
> or December or Dec, then ISO8601 does not apply.
suppose. I use the Year-Month-Day date format all the time,
usually fully numeric; but there are times when the date
needs the Month in words, or appending the Day Name may be
useful to the reader. In these cases I always use the
Year-Month-Day (DayName) ordering as this is the same as in
the Numeric version; with additional, perhaps redundant, info
included in brackets. However these forms not defined in the
standard, as the standard only covers fully numeric
representations. I always use the Year-Month-Day ordering
so I can interchange '2000-Dec-31' and '2000-12-31' at will.
People who continue to write '31 Dec 2000' are also likely
to be using the '31/12/00' format as their numeric shorthand.
People who continue to write 'Dec 31, 2000' are also likely
to be using the '12/31/00' format as their numeric shorthand.
The day after '01/01/01', less than three weeks from now,
these people will soon run into problems. Think in terms of
Year-Month-Day for all your date formats, not just the
numeric ones, is my simple message.
> I would also suggest that the standard does not apply whenI agree with this.
> you augment a standard form with additional information. In
> the case of YYYY-MM-DD, the addition of Monday or ---1 may
> be convenient to the reader but redundant in the strictest
> sense. I think its great to use at least one of the ISO8601
> forms, but additional courtesies fall outside the standard.
> Nor does the standard allow for catenation of alternate
> forms; 2000-12-10---7 is undefined. One might follow a
> standard form with parenthetical information in any form,
> 2000-12-12 (Monday)
> 2000-347 (--W50-1, December 12)
> When spelling out names of months, some of us still like toAbsolutely. You will see this in action already on many Web
> use forms that teach the Year-Month-Day mindset.
Sites. The most obvious is on <http://ftpsearch.lycos.com/>
when a list of files is returned for your search. I use this
format at the start of all my emails. I reckon that people
who have never heard of ISO 8601, will have less of a problem
deciding what '2000-Dec-14' means, compared to reading
'2000-12-14' (especially for all dates within the first 12
days of each month... where the Month Number and Day Number
are both less than 12... e.g. 2001-03-05 where I would
write 2001-Mar-05 i nstead).
> While Monday and December are conversational andThere are going to be a few times when people need to do
> pronouncable for persons reading the date aloud or
> subvocalizing, I think alphabetic abbreviations such as
> Mo and Dec ought to be either spelled out in full or
> abbreviated numerically according to ISO8601.
something not defined by the ISO 8601 standard. In these
cases my only recommendation is to use the same
Year-Month-Day Hour:Minute:Second ordering as in the
standard, solely for the sake of logic. The Day Name, though
redundant, is best placed after the Day Number but before
the Time information. And where the Era (BC/BCE or AD/CE)
is specified, use this as a prefix to the date, in order
to avoid writing either '2000-12-14 (Thursday) AD' or
'2000-12-14 AD (Thursday)'.
I prefer 'AD 2000-12-14 (Thursday)' instead.
I would also suggest that a date and time specified like
2000 Dec 14 (Thu) 18:59:59
even though not fully 'ISO Compliant' is far more readable than
Thu 14 Dec 18:59:59 2000
though the latter seems to be the format usually obtained
from computers running various versions of Unix and Linux.
Astronomers have been using the Year-Month-Day format in various
ways for over 200 years. Astronomers sometimes also use decimal
fractions of a day, in place of Hours, Minutes and Seconds. So,
in tables of Astronomical Information you may get results like:
2000 R r x
Jan 01.00 4.67 2.34 346.9
Feb 04.25 5.46 1.36 245.6
Mar 12.90 6.54 0.97 134.5
2000 Jan R r x
04d 00h 5.95 2.68 266.0
14d 06h 6.80 2.24 218.8
22d 23h 30m 8.38 1.87 184.4
The ordering is Year-Month-Day-Time. The markers d, h, and m are
used to show which items are the Day, Hour, or Minute for those
people who weren't following the plot. In ISO 8601 these types of
marker are used only when defining Periods of Time.
The above format doesn't explicitly comply with the ISO 8601
standard, but each is absolutely logical in format, with largest
units always specified first, then ordered in decreasing size.
Even today, the BAA (British Astonomical Association) Journal
uses these formats in tables and in texts. And, at the regular
BAA meetings in London the minutes of the previous meeting
perhaps '...beginning two-thousand November twenty-third at
eighteen-thirty hours...' are still read out in this format.