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[IDV #CQE-207112]: Recognition of Fill / Missing value

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  • Subject: [IDV #CQE-207112]: Recognition of Fill / Missing value
  • Date: Thu, 20 Nov 2008 17:43:58 -0700
Hi Chris:

looking at a random 2D variable:

  short AerosolOpticalThicknessPassedThresholdStd(lat=720, lon=1440);
     :_CoordinateAxes = "lat lon ";
     :_FillValue = -32767s; // short
     :units = "NoUnits";
     :Title = "Standard deviation of the spectral Single  ScatteringAlbedo ss 
of aerosol models that passed the threshold.Scaled by a factor 1000.";
     :UniqueFieldDefinition = "OMI-Specific";
     :ScaleFactor = 0.0010; // double
     :Offset = 0.0; // double
     :missing_value = -32767s; // short

ScaleFactor should be scale_factor
Offset should be add_offset

see http://www.unidata.ucar.edu/software/netcdf/docs/BestPractices.html "packed 
data values"

Im detecting missing values ok in toolsUI 4.0. what version IDV?


> Description of problem: We're trying to get our OPeNDAP server with the HDF5 
> handler to work properly
> in IDV.  In general, it seems to be working OK, *except* for an inability of 
> IDV
> to recognize either the missing_value or _FillValue.  Are we misnaming these 
> or
> something?  Or perhaps running into problems with the "short" variable type?
> BTW, Panoply seems to recognize them OK...
> Here is a URL:
> http://acdisc.sci.gsfc.nasa.gov/opendap/Aura_OMI_Level3/OMAEROe.003/2006/OMI-Aura_L3-OMAEROe_2006m0109_v003-2008m0815t092640.he5
> I've looked at both AerosolModelMW and 
> AerosolOpticalThicknessPassedThresholdMean.
> (Of course, I can achieve the same affect by tweaking the color table, but 
> that's
> a bit tedious.)
> 
> Thanks!
> 
> 


Ticket Details
===================
Ticket ID: CQE-207112
Department: Support netCDF Java
Priority: Normal
Status: Open