ImageDM/ObsCore - Dataset

[Douglas Tody]

I agree; collecting this information in the Dataset element is
preferable, and would eliminate one of the more important current
differences between ImageDM/Spectral and ObsCore.    - Doug


On Thu, 31 Oct 2013, CresitelloDittmar, Mark wrote:

> All,
> 
> I thought that I would elaborate on a point in the diagram I sent out
> the other day:
> 
> ImageDM - ObsCore Convergence thread.
>   http://www.ivoa.net/pipermail/dm/2013-October/004778.html
> 
> In that diagram, Observation contains 'dataset specific' metadata such as
> dataProductType and calibLevel.  In the extension, those items move into
> a 'Dataset' object. 
> 
> I did this to resolve, what seems to be a disconnect between the model
> description (text), and mapping (utypes).
> 
> From the description, it seems clear that the intent is that an Image or
> Spectrum *is* a Dataset.. with particular characteristics
> (dataProductType, dataProductSubType, Length).
> 
> In Observation, those items are attributes of the top level object
> "Observation"
>   - but the utypes contain a "Obs" node
> 
> The Observation object also *has* a Curation, DataID, Target.
>   - none of those have a 'Obs' node in their utypes.
> 
> In the old "Spectrum" model, some of these were at the top level too
> "Spectrum.Length".   When we removed 'Spectrum' node, these went to a
> Dataset object to avoid "Length" for a utype.
> 
> So to keep the mapping and model consistent, it seems necessary to have
> the top
> level object be a container of objects at the same level covering the
> different topics.  And so, we have a Dataset object containing dataset
> specific metadata.
> 
> Mark
> 
> 
> 
>