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[netCDFJava #VZT-405755]: skew-t with wrfout data

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  • Subject: [netCDFJava #VZT-405755]: skew-t with wrfout data
  • Date: Wed, 11 Nov 2009 14:43:04 -0700
Hi Randy-

Firstly, please use a new e-mail for each issue instead of just replying to an 
old message or remove the ticket ID from the message.  That way they are logged 
as separate reports and we can more easily keep track of them.  Thanks.

> I have a netcdf file containing temperatures. Some of the grid points
> have values of -999 which i want IDV to interpret as missing. I want to
> use the color-shaded plan view as the option so i can show a basemap
> underneath for those values which are missing (-999). It seems to work
> for the color-filled contour option but the interpolation does not look
> very good between the grid points.

If you are writing the netCDF file, you can indicate the missing value by 
adding a missing_value attribute to the variable.  Set the value to be -999 
using the same type as the variable (int, float, etc).

If you are not writing the file, you can wrap it in an NcML file and load that 
in.   So, to add an attribute to a float variable named temp in a file called 
foo.nc, your NcML file would look like:

<?xml version="1.0" encoding="UTF-8"?>
<netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";
  location="foo.nc">
  <variable name="temp">
    <attribute name="missing_value" type="float" value="-999"/>
  </variable>
</netcdf>

Don Murray

Ticket Details
===================
Ticket ID: VZT-405755
Department: Support IDV
Priority: Normal
Status: Open