[Om3] Being pragmatic about the semantics of, eg, variables and functions

[Professor James Davenport]

On Mon, March 23, 2009 12:07 am, c.a.rowley at open.ac.uk wrote:
>
>
> Well spotted, James: but you are making an (entirely reasonable)
> assumption
> about the measure.
>
> Add |cos z| = 1 to the domain if you wish but then you will complain that
> it is (assuming z is a 'real variable', of course).
Which I did since $z<0$. I (subconsciously) played Axiom in my head and
looked for an ordered set with a cos functions.

>
> -----member-math-request at w3.org wrote: -----
>
> To: c.a.rowley at open.ac.uk
> From: "Professor James Davenport" <jhd at cs.bath.ac.uk>
> Sent by: member-math-request at w3.org
> Date: 22/03/2009 23:14
> cc: "Paul Libbrecht" <paul at activemath.org>, "Math Working Group"
> <member-math at w3.org>, "Professor James Davenport" <jhd at cs.bath.ac.uk>,
> om3 at openmath.org
> Subject: Re: Being pragmatic about the semantics of, eg,
> variables and functions
>
> On Sun, March 22, 2009 8:19 pm, c.a.rowley at open.ac.uk wrote:
>> I also have far too much to say about functions and integration, with
> examples (only 1-dimensional) such as:
>>
>> \int _{ |\cos(z)| < 1  and z < 0 } ( sin \invisibletimes exp )
> I'm not sure what this is intended to convey. Since $|\cos z|\le1$, we are
> only excluding a set (admittedly infinite, but only finite over a finite
> range) of isolated points.



James Davenport
Visiting Full Professor, University of Waterloo
Otherwise:
Hebron & Medlock Professor of Information Technology and
Chairman, Powerful Computing WP, University of Bath
OpenMath Content Dictionary Editor and Programme Chair, OpenMath 2009
IMU Committee on Electronic Information and Communication