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20040927: netCDF Fortran (77 + 90) - help with reading netcdf files (cont.)

>From: SIVARAM VENKATA PATIBALLA <address@hidden>
>Organization: Western Michigan
>Keywords: 200409262302.i8QN2xCl006532  netCDF NCAR reanalysis

Sivaram,

>Trying to run readgeneral.f since
>ncdump gives me output, but not all the values

ncdump can list out all of the data in a netCDF file, only
the header of a netCDF file, and full lists for specified
variables.  It does not, however, allow you to request
a subsetted list of values for a particular variable.

For instance, you can get the names of the variables in
your netCDF file using 'ncdump -h':

ncdump -h uwnd.1981

This assumes that the name of your file is actually 'uwnd.1981'.  If it
is different, use the correct name.

Now, assume that the name of the u-wind variable is 'uwind'.
You can list out all of the 'uwind' values using:

ncdump -v uwind uwnd.1981

The man page for ncdump tells you about what is possible.

>say i open uwnd.1981( u-wind component netcdf file for
>1981) using ncdump, it does not give me the actual
>uwind values for each and every latitude,longitude
>location.

It should.  A simple 'ncdump' invocation should list out all of the
data in the file in ASCII format:

ncdump uwnd.1981

The format of the output may not be what you are after, but the
information is all there.

>I need to open the netcdf file using ncdump
>for 1000, 500 mb level only and get actual u-wind
>values for all the dates in the year ( ex. 1981).

ncdump does not allow you to list out subsets of data for any
variable.

>please could you suggest something

I suspect that you might be better off if you can get readgeneral.f to
compile and link into an executable.  There have been a number of
inquiries about compiling readgeneral.f sent to Unidata User Support
even though this is not our code.  You may want to review the questions
that have been asked already AND our replies to them to help get you
going.

Go to UDUNITS Support Email Archive
http://my.unidata.ucar.edu/mailsearchform.php?query=readgeneral&case=on&whole=on&errors=0&maxfiles=20&maxlines=10

Select 'readgeneral' as the value for 'Search for:' and 'udunits' as
the 'Archive to search'.  You will get a list of past email exchanges
we have had with different users on their attempts of building an
executable from readgeneral.f.

The other thing you might want to investigate are the many packages
that have been made availble by netCDF users:

Unidata HomePage
http://my.unidata.ucar.edu
  Software
  http://my.unidata.ucar.edu/content/software
    netCDF
    http://my.unidata.ucar.edu/content/software/netcdf
      Software for manipulating or displaying netCDF data
      http://www.unidata.ucar.edu/packages/netcdf/software.html

The last page contains links to a variety of packages that folks in
the netCDF community have developed and are making freely available.
Because these packages were not developed here at Unidata, we do
not support them directly.

>thank you

No worries.

>sivaram

Cheers,

Tom Yoksas
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