HDF files

[Don Hooper]

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