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[IDV #ZVU-808324]: IDV v2.3: Profiler data in NetCDF files

Hi Dave-
 
> > IDV guys,
> >
> > Should IDV v2.3 be able to read 1-hourly profiler data (from the
> > FL2 feed) in NetCDF format, such as the attached file? When I read
> > the file, I get what appears to be a list of record headers listed
> > in the "Fields" window, with the choice only of Omni Control in the
> > Displays window (First figure attached).

The IDV only supports reading Profiler data from ADDE servers.  GEMPAK
and McIDAS first decode the netCDF data into their formats because
they need to handle the error flags and the varying vertical datum
(heights are relative to the station).  Rather than reimplement all
that in the IDV, we use the decoded data through ADDE.  Until the
THREDDS group comes up with an API for accessing these data 
from remote servers (or local files) allowing for the types
of subsetting that we get from ADDE, we'll have to stick to the
ADDE access.

> > Creating a display from this one available choice, I get the Omni
> > Control spreadsheet (second figure attached).
> >
> > Clicking on the Mappings button in the spreadsheet appears to allow
> > me to specify some mappings that might produce a plot of profiler
> > data (third figure attached), but short of guessing semi-randomly
> > about what the mappings should be, I'm not sure what to do next.
> > Selecting some of the items in the "Map from:" column register
> > recognizable units (e.g., "levels" and "Pressure"), while others
> > produce a quizzical look ["Unit=none"] (e.g., "level" and
> > "vcomponent" and "wcomponent").

The IDV defaults to the VisAD netCDF reader for these data which 
will read any netCDF-3 file.  The Omni control can then be used
to create some displays of the data where the user can set the
mappings of data to display types any way they want.  You do
not have the slicing and regrouping capabilities like you have
in the main IDV displays which are tailored to the types of data
that they handle.  

> > (Was this covered on the first day of the IDV workshop--the day I

I think we just gloss over the Omni control.

> > I want to see if I can plot a time series of a profile of wind
> > barbs, for example. Perhaps I'm being naive--maybe there are data
> > only from a single time but from multiple stations in there--I'm
> > not actually sure.

I think that's what the netCDF files have - either a 6 minute or 
hourly summary of multiple stations at one tim.

> > Any guidance would be appreciated--the User Guide seems a little
> > terse on this topic, possibly because the possibilities are many.

Actually, you are just limited to accessing the profiler data through
the profiler chooser.  But you are correct that the Omni control
is very powerful and the possibilities are many.  We'll look at the
docs and see if we can beef them up a bit.


Don

Ticket Details
===================
Ticket ID: ZVU-808324
Department: Support IDV
Priority: Normal
Status: Open