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Re: question about lexical and value spaces

From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
Date: Thu, 10 Jan 2008 12:58:06 -0500 (EST)
Message-Id: <20080110.125806.156719137.pfps@research.bell-labs.com>
To: mike@saxonica.com
Cc: www-xml-schema-comments@w3.org

From: "Michael Kay" <mike@saxonica.com>
Subject: RE: question about lexical and value spaces
Date: Thu, 10 Jan 2008 18:03:46 -0000

> > The kind of datatype that I was interested in was a datatype 
> > with uncountably many values, e.g., reals.
> 
> I'm rather intrigued by this, even if there is no relevance to XML Schema.
> Am I right in remembering that algebraic numbers are countable but
> transcendentals are not? 

Correct.

> How do you represent the uncountable
> transcendentals on a digital computer?

You can't represent them all, which is the entire point.  There will be
reals that you cannot write, and that will never show up in computions.
(Of course, there are integers that have never shown up in computations,
and there always will be.)  

> Michael Kay
> http://www.saxonica.com/

peter
Received on Thursday, 10 January 2008 18:24:23 GMT

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