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[netCDF #LTW-914869]: netCDF Download help

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  • Subject: [netCDF #LTW-914869]: netCDF Download help
  • Date: Wed, 16 Sep 2009 16:16:36 -0600
Hi Tierney,

> Hi my name is Tierney Foster-Wittig.  I am a graduate student at Duke
> University and I am currently trying to open NetCDF files.

To open netCDF files from MATLAB using only the MATLAB software, the
netCDF files must be in either the netCDF-3 "classic" or "64-bit
offset" format.  In particular, the version of MATLAB you are using
does not yet support reading netCDF-4 files or netCDF-4 classic model
files.

If you have the "ncdump" program that is part of the netCDF software, you can 
tell
what kind of files you have with the "-k" parameter to ncdump.  For example, if 
you have a netCDF file named "foo.nc", invoke ncdump as follows

  ncdump -k foo.nc

and the output should be one of 

  classic
  64-bit offset

If it is anything else, including 

  netCDF-4
  netCDF-4 classic model
  ncdump: foo.nc: NetCDF: Unknown file format

then MATLAB cannot read it.  If you don't have "ncdump", other ways of
determining what kind of file you have are described here:

  
http://www.unidata.ucar.edu/software/netcdf/docs/faq.html#Large%20File%20Support5

The way you open a netCDF file named "foo.nc" for reading in MATLAB is
described in the MATLAB documentation as

  ncid = netcdf.open( 'foo.nc', 'NC_NOWRITE');

See this URL for some additional examples of how to expore the data in
the file after it has been opened:

  
http://www.mathworks.com/access/helpdesk/help/techdoc/import_export/f5-86568.html#brrbr9v-1

> ... However, I am having trouble downloading what I need to download
> in order to view these files.  I was wondering if you could give me
> a step-by-step process so I know what it is I need to download first
> and so on until I am able to open the NetCDF files.  I have tried
> many different downloads but I must be missing something each time
> because nothing has worked.
> 
> I am working on a PC with WindowsXP.  I have MatLab R2009a which I know is
> capable of opening up NetCDF files some how but I cannot seem to get it to
> work.  I am open to downloading other programs in order to open these
> files.  I just need to be able to open these files so any help you could
> give me would be greatly appreciated.

For more help, please consult the MATLAB support site:

  http://www.mathworks.com/support/?s_cid=support

For Windows systems, it's easist to use the built-in netCDF support in
the Windows version of MATLAB, but there are also other ways to access
netCDF data in MATLAB:

  http://www.unidata.ucar.edu/netcdf/software.html#MATLAB

--Russ

Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: LTW-914869
Department: Support netCDF
Priority: Normal
Status: Closed