[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[netCDF #JLR-979347]: fortran code to read a 3d netcdf file

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: [netCDF #JLR-979347]: fortran code to read a 3d netcdf file
  • Date: Tue, 31 Mar 2015 14:39:06 -0600
Yihua,

> Thank you very much for catching the problem.  The range of the
> values should be from 0 to 100.
> The undefined values are 9999.  Now, Grads shows the value ranges from 0
> to 55000.  It might be
> my grads control file problem?  2013_2014_gvf_seq.dat was created by
> readnet.F, The control file is below:
> 
> dset ^2013_2014_gvf_seq.dat
> undef 9999
> options sequential big_endian yrev
> xdef 5000 linear -180.0 0.036
> ydef 1808 linear  9.936 0.036
> zdef 1 linear 1 1
> tdef 122 linear 00Z01jul2013 3dy
> vars 1
> VEGsfc  0 -1,40,2,1  ** surface Vegetation [%]
> ENDVARS

Sorry, but I don't know much about GrADS or its control files.

If you have a GrADS problem, you might get good advice by
submitting it to the GrADS Users Forum:

  http://iges.org/grads/users.html

You can verify the packed values stored in the data file using
the ncdump utility.

--Russ

> Best Regards!
> 
> Yihua
> On 3/29/2015 12:53 PM, Unidata netCDF Support wrote:
> > Hi Yihua,
> >
> > I notice the variable has a "scale_factor" attribute, but you
> > aren't multiplying the values by the scale factor after you
> > read them, to get the intended values.
> >
> > Could hat be the problem?
> >
> > --Russ
> >
> >> Attached is fortran code to read the netcdf file.
> >> Here is the description of the netcdf file I got.
> >> The fortran program seems run successfully.
> >> However, the outputs does not like right in GraDS,
> >> Could you help me to figure out what problem I got?
> >> Thank you very much!
> >>
> >> Yihua
> >>
> >>
> >> netcdf z1_gvf2013_2014 {
> >> dimensions:
> >> ROW = 1808 ;
> >> COLUMN = 5000 ;
> >> Bands = 122 ;
> >> variables:
> >> short VIIRS_GVF(ROW, COLUMN, Bands) ;
> >> VIIRS_GVF:units = "GVF" ;
> >> VIIRS_GVF:long_name = "VIIRS_GVF" ;
> >> VIIRS_GVF:valid_range = 0s, 1000s ;
> >> VIIRS_GVF:scale_factor = 0.1f ;
> >> VIIRS_GVF:add_offset = 0.f ;
> >> VIIRS_GVF:_FillValue = 9999s ;
> >>
> >> // global attributes:
> >> :PRODUCT_ALGORITHM_VERSION = 1.f ;
> >> :Temporal_Resolution = "3 day" ;
> >> :Spatial_Resolution = "0.05 degree" ;
> >> :RangeBeginningDate\(DOY\) = "001" ;
> >> :RangeEndingDate\(DOY\) = "365" ;
> >> :WestBoundingCoordinate\(degree\) = -180.f ;
> >> :EastBoundingCoordinate\(degree\) = 0.f ;
> >> :NorthBoundingCoordinate\(degree\) = 75.024f ;
> >> :SouthBoundingCoordinate\(degree\) = 9.936f ;
> >> }
> >>
> >>
> > Russ Rew                                         UCAR Unidata Program
> > address@hidden                      http://www.unidata.ucar.edu
> >
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: JLR-979347
> > Department: Support netCDF
> > Priority: Normal
> > Status: Closed
> >
> 
> 
Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: JLR-979347
Department: Support netCDF
Priority: Normal
Status: Closed