RE: [pooma-dev] FieldStencils and Field(Range) views

[James Crotinger]

Jeffrey might be able to help with this - he worked on some restriction type of operators for Fields.

        Jim

> -----Original Message-----
> From: Nils H. Busch [mailto:address@hidden]
> Sent: Friday, June 21, 2002 10:44 AM
> To: pooma-dev
> Subject: Re: [pooma-dev] FieldStencils and Field(Range) views
>
>
> James Crotinger wrote:
>
> >
> >
> > There is, in general, no good way to construct metric
> information for
> > a range view of a field, which is why range views evaluate
> to Fields
> > with NoGeometry. For instance, if you have a non-uniform
> > non-orthogonal coordinate system and you remove every other
> point in
> > one direction, the new mesh is no longer a simple sub-mesh
> of the old
> > mesh, and there is no general way for Pooma to calculate this new
> > information. For fields with cartesian coordinates this
> could be done,
> > but such discrimination would have required the coordinate
> system type
> > to be a compile time quantity, and in the re-design of
> Fields our main
> > customers really wanted us to reduce the number of template
> > dependencies (helps code-bloat, compile time, . . .).
> >
> >         Jim
> >
>
> Thanks for pointing this out.
>
> How do I then proceed to write something like
>
> lhs = Function(restriction(rhs(R)));
>
> where lhs is a coarse resolution field, rhs a finer
> resolution field, R some range and restriction a function
> that performs some restriction operation from fine to coarse,
> so that the right hand side of the assignment is transformed
> into a POOMA _expression_ tree ( with as few temporary fields
> as possible) ?
>
> Any suggestions appreciated.
>
>
> --
>     Nils H. Busch
>     Max-Planck-Institute of Cognitive Neuroscience
>     phone:  ++49 (341) 9940-035 fax:  ++49 (341) 9940-204
>     e-mail: address@hidden
>
>
>