[no subject]

Tom,

>Date: Tue, 31 Mar 1998 10:44:02 -0600 
>From: Tom Rink <rink@xxxxxxxxxxxxx>
>To: visad-list@xxxxxxxxxxxxx

In the above message, you wrote:

> 
> >Is it better to return the following VisAD MathType:
> > 
> >    (FunctionType (Real): (time) -> (lat, lon), FunctionType:
> >    (time) -> FunctionType (Real): (altitude) -> (pressure, temperature))
> > 
> >which is a Tuple of two, separate Fields -- or this, equivalent, one:
> > 
> >    (FunctionType (Real): (time) -> (lat, lon, 
> >    FunctionType (Real): (altitude) -> (pressure, temperature)))
> >
> >which is a Field with a Tuple range comprising two Scalars and a Field?
> >
> >--Steve
> 
> Hi Steve,

> In the latter case, lat and lon are not grouped into a tuple which wouldn't
> be desirable if they are to have a reference tuple type.  For example, 
> map coordinates.

Ok.  But, then, which one of these is better?

    (FunctionType (Real): (time) -> (lat, lon), FunctionType:
    (time) -> FunctionType (Real): (altitude) -> (pressure, temperature))

or

    (FunctionType: (time) -> ((lat, lon), 
    FunctionType (Real): (altitude) -> (pressure, temperature)))

The second one allows one to associate a CoordinateSystem with the (lat,
lon) RealTuple -- which can also be done in the first one.

--------
Steve Emmerson   <http://www.unidata.ucar.edu>