## DATETIME@C4VLPLISTSERV01.LOC.GOV

#### View:

 Message: [ First | Previous | Next | Last ] By Topic: [ First | Previous | Next | Last ] By Author: [ First | Previous | Next | Last ] Font: Proportional Font

Subject:

Re: On the usefulness of x

From:

Date:

Tue, 28 Jun 2011 15:49:09 -0400

Content-Type:

text/plain

Parts/Attachments:

 text/plain (46 lines)
 ``` From: Edward C. Zimmermann > It does not mean the same thing. 1950/1959 is an interval (a set of > points, linearly ordered containg all the points in-between the start > and end) and its precision is that of year. 195x is a point and its > precision is 10 years. Are you saying that 195x means some instant in time within the interval 1950/1959? That's certainly not what I thought was intended. Now while I don't suggest that that isn't a real requirement, and it certainly isn't otherwise supported by the spec, if you want to say "some instant in time with the interval 1950/1959" why wouldn't someone want to say "some instant in time with the interval 1955/1958"? The x notation won't be of any use for that, it's only good on a decade boundary. > I think I did a rather long expose of points and intervals some time > ago.. I think we're all clear on the concepts. > Or shall the chorus now suggest that 1999, 1999-02, 1999-02-01, 1999- > 02-01T12:00 are all intervals too?  No. Nobody is (still) suggesting that. I don't think we need to rehash it, I think we all understand the model. However, what I don't want us to have to do is try to articulate it in the spec. > We don't need or want to define the concept of decade, century or .. > But I think we do perhaps want to have a concept of 10 years, 100 years Accepting that for argument sake, if the 10 year period must start on a year divisible by 10, and the 100 year period on a year divisible by 100, that doesn't give you a way to represent an arbitrary 10 year or 100 year period. Nevertheless, if you're happy with that restriction, and since it seems that only you are going to use this, I don't have a problem with defining it as you suggest. > This is not the domain of CQL, at most its for CQL to accept our work Yes that's how I see it. --Ray ```