Handling data cubes in VO

[Doug Tody]

>From Arnold:

> I think that concern is justified since both SIAP and SSAP are so
> strongly designed with 2-D images and 1-D spectra in mind that they
> are not as easily extensible as they could have been.

SIAP is based on the concept of a general ND, regularly sampled "image"
with associated metadata such as a WCS (as has been used within astronomy
for many years).  To keep things simple SIA 1.0 is 2D oriented, but it
can be easily generalized to higher dimensions, just as for example FITS
images can.  The only fundamental restriction for SIA is that the data
be a regularly sampled ND array.

I agree that SSA is more fundamentally 1D oriented.  However, more complex
objects can be modeled as an aggregate of 1D data elements, for example
Echelle, MOS or IFU data (not always, but probably most of the time).

 	- Doug