[Om3] trouble with container markup example

[Professor James Davenport]

On Wed, February 11, 2009 10:08 pm, Paul Libbrecht wrote:
> You are absolutely right Robert,
> and I fear that both OpenMath and MathML content are having
> subset_suchthat (the set of things inside a reference set such that
> some condition holds) but miss
>
>    set_of_expressions_such_that
The reason fro this, as I recall, is to avoid Russell's paradox.
> To serve the purpose below ( {[0,x] | x in R} )
Surely this is map(lambda x.interval(0,x),R).
> and many others where basically one constructs a set by applying
> functions to a few other sets. I think { [x,y] | x in R and y in R }
> is even more difficult.
Non-trivial, but basically because cartesian product don't have
deconstructors.
map(lambda z,interval(z.first,z.second),cartesian_product(R,R))
is basicaly what is wanted.
> Maybe James Davenport or Olga can help here.
Hope this does.

James Davenport
Hebron & Medlock Professor of Information Technology
Formerly 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