Seth, Jim, et al:

Thank you for the constructive alternatives.

--Dave


On Tue, Oct 25, 2016 at 2:26 PM, Seth McGinnis <[email protected]> wrote:

> But then the data is non-compliant, and it sounds like a valid CF
> solution is needed.
>
> Two possible solutions come to my mind.  The first way would be to store
> the undated measurements separately.  Record the normal measurements in
> the normal way, and then record the undated measurements in a separate
> data variable with an index coordinate instead of a time coordinate.
>
> The other way would be not to use time as a coordinate variable at all,
> but only as a data variable.  Record all the measurements with an index
> coordinate instead of a time coordinate.  Then define data variables for
> year, month, day, and time of measurement, and just fill in what's known
> for each one.  (It sounds like the month and year are still known even
> if the day is not.)  This is very similar to the approach taken for
> trajectories; see example H.12 in the spec.
>
> Cheers,
>
> --Seth
>
>
> On 10/25/16 1:31 PM, Dave Allured - NOAA Affiliate wrote:
> > Ajay,
> >
> > I think this is an exception to CF.  I recommend using _FillValue or
> > missing_value on the time coordinate.  Document this in a comment
> > attribute on the time coordinate variable.
> >
> > Also document this somehow in another global attribute that explains you
> > made this exception to the CF conventions.  Follow CF conventions in all
> > other regards.
> >
> > Then, try to remember to warn people about this when you distribute the
> > data.  CF compliant time coordinates are fundamental to many application
> > programs, and I expect they will choke or introduce subtle errors if
> > missing values are in there.  So users will need to provide special
> > handling for such files.  HTH.
> >
> > --Dave
> > (Please reply to list only)
> >
> >
> > On Tue, Oct 25, 2016 at 12:07 PM, Ajay Krishnan - NOAA Affiliate
> > <[email protected] <mailto:[email protected]>> wrote:
> >
> >     Hi All,
> >
> >     I have a user that's converting some IMMA format files to CF
> >     compliant NetCDF files.
> >
> >     The problem is that, we've run into several measurements where just
> >     the hour of measurement has been recorded without the corresponding
> >     "date". We would prefer not to omit these data in the conversion,
> >     because they are considered valid measurements (and play a role in
> >     monthly summary statistics)
> >
> >     How do we represent this in a valid CF NetCDF format since we can't
> >     use _FillValues for 'time'? Any suggestions for handling such
> >     special cases?
> >
> >     Thanks,
> >     Ajay
> >
> >
> >
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