Re: IDV and netCDF FillValue

• To: Brian Blanton <bblanton@xxxxxxxxxxxxx>
• Subject: Re: IDV and netCDF FillValue
• From: Don Murray <dmurray@xxxxxxxxxxxxxxxx>
• Date: Thu, 04 Aug 2005 11:31:15 -0600

Hi Brian-

Brian Blanton wrote:

The fill val is a global attribute, specified as:

         :Fill_Value = 9.96921e+36f ;
         :missing_value = 9.96921e+36f ;

So the macro is expanded, but without underscores.

do I need (2) underscores, and must the fillval be associated
with a variable?

Yes, the convention is that the _FillValue attribute
be associated with each variable.  Using it as a global
variable does not work.  We prefer to use the attribute
missing_value, but either is acceptable.  See the netCDF
best practices page:

http://www.unidata.ucar.edu/software/netcdf/docs/BestPractices.html

section on missing data for a little more info.

Don
*************************************************************
Don Murray                               UCAR Unidata Program
dmurray@xxxxxxxxxxxxxxxx                        P.O. Box 3000
(303) 497-8628                              Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
        "Time makes everyone interesting, even YOU!"
*************************************************************

• References:
  • IDV and netCDF FillValue
    • From: Brian Blanton