Please see my comment below...
On 2014-04-25 7:13 AM, Nan Galbraith wrote:
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>
> #113: Review of CF feature types
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> Reporter: mgschultz | Owner: cf-conventions_at_?
> Type: | Status: new
> enhancement | Milestone:
> Priority: medium | Version:
> Component: cf- | Keywords: featureType, Grid, Point,
> conventions | TimeSeries, Profile
> Resolution: |
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> Comment (by ngalbraith):
>
> With regards to item 1, I'm not sure I see a contradiction between stating
> that "space-time coordinates ...are mandatory" and "If there is only a
> single feature to be stored in a data variable, there is no need for an
> instance dimension." I do agree that the instance variable should be shown
> as an optional field in the table.
Please distinguish between instance dimension and instance variable.
Note that the CF standard says "there is no need for an instance
*dimension*." It does not say there is no need for an instance
*variable* (which may be a scalar if there is only one instance in the
file and no instance dimension).
If the instance *variable* is not present, there will be no variable to
have the cf_role metadata (e.g., cf_role = trajectory_id) and the file
will not be CF DSG compliant. Similarly, if the instance variable is not
present, there is no way for software to aggregate a collection of
instances.
>
> My question on this is whether, in the absence of an instance variable,
> the featureType attribute still should be used, and, if not, whether such
> a file is CF1.6 compliant. This probably has been answered somewhere in
> the email discussion, but should be clarified in the docs.
>
> On item 2, I'm glad you're referring to the Java source; I just did a
> quick search on my email archive, looking for feature type in subject
> lines, and find this cropping up in the netcdf-java and thredds lists as
> well as in cf-metadata.
>
> I have one additional item that's been in 4 or 5 email threads, on which I
> admit to having dropped the ball every time. It's the question of
> describing 2D data from surface moorings as timeSeriesProfile features. Is
> this within the scope of this ticket? I'm sure it's a closed issue for
> most CF folks, but I have lingering questions; don't want to divert the
> effort going on here, though.
>
> Thanks - Nan
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--
Sincerely,
Bob Simons
IT Specialist
Environmental Research Division
NOAA Southwest Fisheries Science Center
1352 Lighthouse Ave
Pacific Grove, CA 93950-2079
Phone: (831)658-3205
Fax: (831)648-8440
Email: bob.simons at noaa.gov
The contents of this message are mine personally and
do not necessarily reflect any position of the
Government or the National Oceanic and Atmospheric
Administration.
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Received on Fri Apr 25 2014 - 10:15:37 BST
