[Om3] Conditions

[Professor James Davenport]

On Mon, November 3, 2008 9:20 am, David Carlisle wrote:
>> What THIS use of interval is doing is
>> asserting intervalness on a set that, a priori, might not be an
>> interval.
>> It is possibly also contradictory to the spec [4.4.2.4.1]:
>
> "this use of condition", I think you intended. I agree it's skirting the
No, I DID mean 'interval'. The use of 'condition' specifies a set, and I
have no problem with that. It's the assertion that this set is an interval
that worries me, i.e. the fact we are using 'interval' rather than 'set'
as the container.
> edge of reasonableness, but I think that edge cases will always take a
> certain amount of goodwill in interpretation:-) but honestly I don't see
> much difference between using the contition/set formulation and
> specifying something that isn't an interval from using (say) the
> domainofintegration form for a contour integral and specifying some
> discrete set that doesn't make sense as a contour. The only difference
I have no problem with that, either. I have no problem with
> is that in the first case one could try to make it impossible to get
> into that situation by insisting that you use the lowlimit/uplimit form
> instead, but since we can't syntactically constrain the second form to
> be a contour, I don't see a lot of gain in banning the syntax that
> allows nonsense to be expressed in the 1 dimensional case as well.
But 4.4.2.4.1 explicitly DOES ban that syntax, I think.

James Davenport
Hebron & Medlock Professor of Information Technology
Formerly RAE Coordinator and Undergraduate Director of Studies, CS Dept
Lecturer on CM30070, 30078, 50209, 50123, 50199
Chairman, Powerful Computing WP, University of Bath
OpenMath Content Dictionary Editor
IMU Committee on Electronic Information and Communication