Re: [thredds] Thredds-Error when serving a nc-file in opendap

• To: "Antonio S. Cofiño" <antonio.cofino@xxxxxxxxx>
• Subject: Re: [thredds] Thredds-Error when serving a nc-file in opendap
• From: Heiko Klein <Heiko.Klein@xxxxxx>
• Date: Wed, 16 Jan 2013 10:00:35 +0100

Antonio,

Heiko

On 2013-01-15 16:29, "Antonio S. Cofiño" wrote:

Heiko,

The netcdf file is wrongly defined and the OpenDAP service gets confused
when a variable array has a dimensión with no size.

The Polar_Stereographic_Grid variable is in fact a dimensionless
variable been used for defining a geo projection following the CF
convention:
http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.0/cf-conventions.html#grid-mappings-and-projections


The Netcdf file appears to generated a dimensionless variable (scalar
variable or 0-dim variable) using an unlimited dimension with no size.

One solution is to regenerate the file.

The other way is to re-publish the dataset using NCML to remove the
dimension and redefining the variable. Please loak at the attache file
and the the resulting dataset in:
http://www.meteo.unican.es/thredds/catalog/SANDBOX/catalog.html?dataset=SANDBOX/GLO_9_jostedal_LT5_20060916_104312_polar.ncml


(remember to modify the location to your local file)

Regards

Antonio

--
Antonio S. Cofiño
Grupo de Meteorología de Santander
Dep. de Matemática Aplicada y
         Ciencias de la Computación
Universidad de Cantabria

El 15/01/2013 12:31, Heiko Klein escribió:

Hi,

I have a problem serving a netcdf-file as opendap stream. The file is
based at:

http://thredds.met.no/thredds/catalog/cryoclim/met.no/GLO/catalog.html?dataset=cryoclim/met.no/GLO/GLO_9_jostedal_LT5_20060916_104312_polar.nc



When requesting the default as ASCII, I get:

Error {
    code = 3;
    message = "Invalid Parameter Exception:
DArrayDimension.setProjection: Bad Projection Request: stop < 0";
};


When requesting the variable Polar_Stereographic_Grid, I get an error
code:

Error {
    code = 5;
    message = "Illegal index for range last index";
};


ncWMS/thredds for this file works fine. I guess the culprit is the
definition of Polar_Stereographic_Grid:

         polar = UNLIMITED ; // (0 currently)
variables:
         int Polar_Stereographic_Grid(polar) ;


i.e. a 0-size unlimited variable. In fact, the
Polar_Stereographic_Grid is just a attribute-container for the
grid-mapping, so dimensions shouldn't matter.


We're using thredds 4.2.9 with tomcat 6.0.X in production and I tested
it with thredds 4.3.15 with tomcat 7.0.X. Both thredds versions have
the same behaviour.


Best regards,

Heiko

--
Dr. Heiko Klein                              Tel. + 47 22 96 32 58
Development Section / IT Department          Fax. + 47 22 69 63 55
Norwegian Meteorological Institute           http://www.met.no
P.O. Box 43 Blindern  0313 Oslo NORWAY

• References:
  • [thredds] Thredds-Error when serving a nc-file in opendap
    • From: Heiko Klein
  • Re: [thredds] Thredds-Error when serving a nc-file in opendap
    • From: "Antonio S. Cofiño"