HDF files

[Dan Holloway]

Hoop,

  Can the DSET lines in DDF files use DODS URLs similar
to the sdfopen interface?

  Dan

On Wed, 2005-02-02 at 16:41, Don Hooper wrote:
> Andreea Ira,
>
> Just lose the ZDEF line from the DDF.  If you use one, it must name a
> dimension.  I don't see any dimension in your data file that qualifies, so
> just don't use one.  All lines in the XDFopen-style DDFs are optional
> except for DSET.
>
> -Hoop
> > From owner-gradsusr at LIST.CINECA.IT  Wed Feb  2 12:54:34 2005
> > From: Andreea Ira <andreea_ira at YAHOO.COM>
> >
> > Dear all,
> >
> > I am having some troubles in completing the task of
> > reading and displaying data in hdf format using GrADS
> > and I would appreciate your assistance.
> >
> > Since according to the directions to read and display
> > the data in question, I need to create a .ddf file, I
> > did so using the information that I can obtain from a
> > dump (created using hdf binaries and following the
> > from the README file).
> >
> > 1.  I include here the contents of the dump file:
> >
> > dimensions:
> >         2_5_deg__regional_colat__zones = 72 ;
> >         2_5_deg__regional_long__zones = 144 ;
> >         days = 31 ;
> >         hours = 24 ;
> >         5_0_deg__regional_colat__zones = 36 ;
> >         5_0_deg__regional_long__zones = 72 ;
> >         10_0_deg__regional_colat__zones = 18 ;
> >         10_0_deg__regional_long__zones = 36 ;
> >         2_5_deg__zonal_colat__zones = 72 ;
> >         5_0_deg__zonal_colat__zones = 36 ;
> >         10_0_deg__zonal_colat__zones = 18 ;
> >         2_5_deg__global_zone = 1 ;
> >         5_0_deg__global_zone = 1 ;
> >         10_0_deg__global_zone = 1 ;
> >
> > variables:
> >         float
> > Solar_incidence(2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> >                 Solar_incidence:_FillValue =
> > 3.4028235e+38f ;
> >                 Solar_incidence:valid_range = 0.f,
> > 500000.f ;
> >                 Solar_incidence:long_name = "2.5
> > Degree Regional, Monthly (Day), Total-sky Averages" ;
> >                 Solar_incidence:units = "Watt hours
> > per square meter" ;
> >         float
> > Net_radiant_flux(2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> >                 Net_radiant_flux:_FillValue =
> > 3.4028235e+38f ;
> >                 Net_radiant_flux:valid_range = -200.f,
> > 200.f ;
> >                 Net_radiant_flux:long_name = "2.5
> > Degree Regional, Monthly (Day), Total-sky Averages" ;
> >                 Net_radiant_flux:units = "Watts per
> > square meter" ;
> >         float
> > Longwave_flux(2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> >                 Longwave_flux:_FillValue =
> > 3.4028235e+38f ;
> >                 Longwave_flux:valid_range = 50.f,
> > 450.f ;
> >                 Longwave_flux:long_name = "2.5 Degree
> > Regional, Monthly (Day), Total-sky Averages" ;
> >                 Longwave_flux:units = "Watts per
> > square meter" ;
> >         float
> > Shortwave_flux(2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> >                 Shortwave_flux:_FillValue =
> > 3.4028235e+38f ;
> >                 Shortwave_flux:valid_range = 0.f,
> > 1400.f ;
> >                 Shortwave_flux:long_name = "2.5 Degree
> > Regional, Monthly (Day), Total-sky Averages" ;
> >                 Shortwave_flux:units = "Watts per
> > square meter" ;
> >         float Albedo(2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> > Longwave_flux:units = "Watts per square meter" ;
> >         byte Number_of_hours_of_longwave_flux(days,
> > 2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> >
> > Number_of_hours_of_longwave_flux:valid_range = '\0',
> > '\30' ;
> >
> > Number_of_hours_of_longwave_flux:_FillValue = '\177' ;
> >
> > Number_of_hours_of_longwave_flux:long_name = "2.5
> > Degree Regional, Daily, Total-sky Averages" ;
> >                 Number_of_hours_of_longwave_flux:units
> > = "hours" ;
> >         float Shortwave_flux(days,
> > 2_5_deg__regional_colat__zones,
> > 2_5_deg__regional_long__zones) ;
> >
> > 2.  I used information from here to create a .ddf file
> > that will then be used with the GrADS xdfopen file
> > command.  I include the file here (I followed the
> > example provided by the GrADS web site that describe
> > this):
> >
> > DSET ^CER_ES4_Aqua-FM3_Edition2_024024.200207
> > TITLE This is only a test
> > UNDEF 1.0E15
> > XDEF 2_5_deg__regional_long__zones 144 LINEAR -180.0
> > 2.5
> > YDEF 2_5_deg__regional_colat__zones 91 LINEAR  -90.0
> > 2.0
> > TDEF days 31 LINEAR 0Z01JUL2002 1MO
> > ZDEF 1 LEVELS 1000
> > VARS 5
> > Solar_incidence=>solin 0 99 Incident Radiation
> > Net_radiant_flux=>netflux 0 99 Net radiation
> > Longwave_flux=>lwflux 0 99 Longwave flux
> > Shortwave_flux=>swflux 0 99 Shortwave flux
> > Albedo=>albedo 0 99 Albedo
> > ENDVARS
> >
> > 3.Finally, when I try to open the file in GrADS using
> > xdfopen command, I receive these errors:
> >
> > XDFopen Error:  Missing or invalid dimension size.
> >   --> The invalid description file record is:
> >   --> zdef 1 levels 1000
> >   The data file was not opened.
> >
> > I am using grads 1.8SL11
> >
> >
> > Thank you,
> >
> > Andreea Ira