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[IDV #MRV-291694]: trouble with netCDF file

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  • Subject: [IDV #MRV-291694]: trouble with netCDF file
  • Date: Wed, 04 Feb 2009 12:54:51 -0700
Hi Dave-

> I am going to contact the NWS about this....they want feedback on the
> usefulness of the data!

Sounds good.

> Last month I asked you about what it would take to extend the xml files
> for reading in picture files that weren't in lat/lon projections. Could
> that concept also be used in reading in netCDF files that don't contain
> valid geolocation info? Essentially, providing a mechanism to geolocate
> any type of array data [netCDF, text, gif, jpeg, etc.] after-the-fact.
> Similar to MAKNAV in McX.

In this instance, I would use NcML.  You can enhance the file to include
the appropriate information. 

Don 

> Unidata IDV Support wrote:
> > Hi Dave-
> >
> >
> >> Full Name: Dave Santek
> >> Email Address: address@hidden
> >> Organization: SSEC
> >> Package Version: 2.6u1 build date:2009-01-29 22:02 UTC
> >> Operating System: Windows XP
> >> Hardware: Java: home: C:\Program Files\IDV_2.6u1\jre version: 1.6.0_11 
> >> j3d:1.5.2 fcs (build4)
> >> Description of problem: Hi,
> >>
> >> I'm trying to display a netCDF file from: 
> >> http://water.weather.gov/download.php
> >> I have an example at:
> >> ftp://ftp.ssec.wisc.edu/pub/ssec/daves/nws_precip_conus_20090129.nc
> >>
> >> When trying to load it as a netCDF grid, the error is:
> >> "No gridded data found"
> >>
> >> It does not contain lat/lon by pixel; it is in a polar stereographic 
> >> projection [corner points
> >> provided along with some projection information].
> >>
> >> I tried one of the CF-compliant checkers:
> >> http://puma.nerc.ac.uk/cgi-bin/cf-checker.pl
> >>
> >
> > It is nowhere near a CF compliant file.
> >
> >
> >> and it came up with 9 warnings....but, no errors. Wouldn't that indicate 
> >> the
> >> file should be usable in the IDV?
> >>
> >
> > I would think the first warning would indicate that this doesn't have the CF
> > Conventions attribute.
> >
> > In any case, this is not what I would call a "self describing" format.  
> > There
> > is no documented standard (except in some C code according to the web page).
> >
> > One could write a convention handler for this, but I'm not sure if it's 
> > worth
> > the effort.
> >
> > A better effort would be to get the NWS to write out CF compliant netCDF 
> > files. ;-)
> >
> > Don
> >
> > Ticket Details
> > ===================
> > Ticket ID: MRV-291694
> > Department: Support IDV
> > Priority: Normal
> > Status: Open
> >
> >
> 
> 
> --
> 
> Dave Santek
> 
> CIMSS/SSEC
> 
> University of Wisconsin-Madison
> 
> 1225 W. Dayton St.
> 
> Madison, WI  53706
> 
> Phone: 608-263-7410
> 
> 
> 


Ticket Details
===================
Ticket ID: MRV-291694
Department: Support IDV
Priority: Normal
Status: Open