On Wed, 29 Jun 2011 18:14:06 +0200, [UTF-8?]SaaÅ¡ha Metsärantala wrote
> The x-letter has lead to several misunderstandings. I tentatively suggest
I do not think that 'x' has led to any misunderstandings rather I suspect
that the concept of precision applied to dates continues to meet with
1x == P10(1n)
1xx == P100(1nn)
1xxx == P1000(1nnn)
where n is any of 0..9 and P10, P100 and P1000 could be read as precision of
10, resp. 100 and 1000.
196x matches P10(1962), P10(1968).. in fact any of 1960..1969
While a more general precision qualifier (Pn) might be more generic, in
practice, I do suspect that-- like the year, month, day, hour or minute
precision we have implicitly defined within ISO 8601-- decade (10 years)
and "century" (100 years) are (by far) the most common. Both decade and
century are so deeply embeded in western culture that these "arbitrary"
marks effect events themselves.
While I am on the topic.. Ray has suggested that in intervals the start and
end are of the same precision. I do not agree. The most trivial counter-
example are open intervals but we often have less precise start than end
points. Example: 1763/1776-07-04
Looking at more contemporary events.. When did the movement to topple Hosni
Sayyid Mubarak start? He resigned on 11 Feb 2011 but when did the
demonstartions start? Our measurement precision is not very good. 25 Jan? 17
Jan? 23 Jan (when the Muslim Brotherhood announced their intent to
participae in the 25 Jan demo)? 2 Feb? Or much earlier? In Tunesia we can,
at best, agree on Dec 2010 as the start there... Mohamed Bouazizi setting
himself ablaze on 17 Dec 2010 became a symbol that gave the movement some
media momentum but it was not the start of the escalation.. All we really
have is 14 Jan 2011 as the date when Ben Ali was ousted.. There are loads of
similiar examples.. The Russian Revolution, for example, is a collective
name for a series of "revolutions".. We call them collectively the "1917
Examples where the start is of a higher precision than end, I think, are
also easy to think of... When, for example, did the Soviet Union end? Dec.
1991? 25 Dec. with the resignation of Gorbachev or in early 1992 with the
establishment of the "commonwealth"?
On Fri, 1 Jul 2011 17:50:26 +0200, [UTF-8?]SaaÅ¡ha Metsärantala wrote
> > > the "x"-concept [...] in the context of CQL.
> > It doesn't make sense to me.
> I would be pleased to discuss this further within the context of a list
> about CQL or another query related list. Of course, we could extend EDTF
Those in the CQL and other query language communities are invited to join
this discussion. This list has been announced serveral times, for instance,
in various CQL, SRU/W and Z39.50/ISO23950 lists.
Edward C. Zimmermann, NONMONOTONIC LAB