Thank you Dave, I will explore that option a bit. But It surprises me that
the netcdf C++ libraries do not support HDF-EOS files, since I have no
problem using the ncdump utility to explore the contents of a local (or
OpenDAP URL) MERRA HDF file.
On Mon, Dec 17, 2012 at 1:00 PM, David W. Pierce <dpierce@xxxxxxxx> wrote:
> Hi Taylor,
>
> it's been a few years since I analyzed HDF-EOS data, but in case it's
> useful, I'll offer that at that time HDF-EOS was a specialized kind of
> *HDF* file, not a specialized kind of netcdf file. You need a separate
> HDF-EOS library to access those files, not the netcdf4 library.
>
> Maybe things have changed, but you might be better off first looking
> for HDF-EOS specific libraries.
>
> Regards,
>
> --Dave
>
>
> On Mon, Dec 17, 2012 at 9:35 AM, Taylor Binnington
> <tbinnington@xxxxxxxxx> wrote:
> > Thank you for the replies.
> >
> > I see. I'm still learning the differences between these file formats. It
> > appears that MERRA climate data is stored in HDF-EOS format, which is a
> > specialized kind of NetCDF-4... what are the chances that I will ever be
> > able to read this, even with newest versions of NetCDF with some HDF5 and
> > HDF4 support?
> >
> > I am running netcdf-4.0.1-19.1, since that is what was available in the
> > openSUSE geo repository as an rpm (therefore no, I did not make check
> before
> > installing). I will uninstall this and manually install the binaries to
> test
> > the most current version (with fingers crossed that HDF-EOS is
> supported).
> >
> >
> > On Mon, Dec 17, 2012 at 11:56 AM, Russ Rew <russ@xxxxxxxxxxxxxxxx>
> wrote:
> >>
> >> Taylor,
> >>
> >> More recent versions of netCDF-4 can access HDF5 data (and even HDF4
> >> data) that was not written by netCDF-4, but not arbitrary HDF5 files.
> >> Interoperability with HDF5 is documented here:
> >>
> >>
> http://www.unidata.ucar.edu/netcdf/docs/interoperability_with_hdf5.html
> >>
> >> and in these FAQs:
> >>
> >> http://www.unidata.ucar.edu/netcdf/docs/faq.html#fv20
> >> http://www.unidata.ucar.edu/netcdf/docs/faq.html#fv15
> >>
> >> If netCDF-4 gets a segfault opening an HDF5 file, that's either a bug in
> >> the legacy C++ library you're using or a bug in the accessing program.
> >>
> >> I just tried this example C++ program with the C++ library in netCDF
> >> version 4.1.3:
> >>
> >> http://www.unidata.ucar.edu/netcdf/examples/programs/simple_xy_rd.cpp
> >>
> >> changing the test file to a file that doesn't exist, and
> >> it seemed to behave correctly:
> >>
> >> $ ./simple_xy_rd
> >> Couldn't open file!
> >>
> >> What version of the netCDF C++ library are you using? Did you run "make
> >> check" before installing it?
> >>
> >> --Russ
> >>
> >> > Hi Taylor:
> >> >
> >> > The netcdf library can not open arbitrary HDF files, only ones built
> >> > with the
> >> > netcdf4 library. If this file was not built with the netcdf4
> library,
> >> > then
> >> > yes you will get an error.
> >> >
> >> > HTH,
> >> >
> >> > -Roy M.
> >> > On Dec 17, 2012, at 8:14 AM, Taylor Binnington <tbinnington@xxxxxxxxx
> >
> >> > wrote:
> >> >
> >> > > Hi all,
> >> > >
> >> > > This is my first time using the NetCDF C++ libraries, and I can't
> seem
> >> > > to g
> >> > et started. I would like to open an HDF file from a program using
> >> > NcFile, usi
> >> > ng the following:
> >> > >
> >> > > NcFile dataFile("MERRA300.prod.assim.inst3_3d_asm_Cp.20120101.hdf",
> >> > > NcFile:
> >> > :ReadOnly);
> >> > >
> >> > > However, gdb reveals a segfault at this line (yes, the file is
> stored
> >> > > in th
> >> > e same directory as the test script). Interestingly, I also receive
> the
> >> > same
> >> > error when I intentionally attempt to open a file that does not exist,
> >> > which
> >> > I find strange (I would have expected a 'file not found' type of
> error),
> >> > and
> >> > it makes me think that I simply can not open an HDF file with these
> >> > libraries
> >> > . Is this true? How would I proceed? Thank you in advance,
> >> > >
> >> > > Taylor Binnington
> >> > >
> >> > > --
> >> > > Taylor Binnington
> >> > > e. tbinnington@xxxxxxxxx
> >> > > c. 647 926 4144
> >> > >
> >> > > _______________________________________________
> >> > > netcdfgroup mailing list
> >> > > netcdfgroup@xxxxxxxxxxxxxxxx
> >> > > For list information or to unsubscribe, visit:
> >> > > http://www.unidata.ucar.edu
> >> > /mailing_lists/
> >> >
> >> > **********************
> >> > "The contents of this message do not reflect any position of the U.S.
> >> > Governm
> >> > ent or NOAA."
> >> > **********************
> >> > Roy Mendelssohn
> >> > Supervisory Operations Research Analyst
> >> > NOAA/NMFS
> >> > Environmental Research Division
> >> > Southwest Fisheries Science Center
> >> > 1352 Lighthouse Avenue
> >> > Pacific Grove, CA 93950-2097
> >> >
> >> > e-mail: Roy.Mendelssohn@xxxxxxxx (Note new e-mail address)
> >> > voice: (831)-648-9029
> >> > fax: (831)-648-8440
> >> > www: http://www.pfeg.noaa.gov/
> >> >
> >> > "Old age and treachery will overcome youth and skill."
> >> > "From those who have been given much, much will be expected"
> >> > "the arc of the moral universe is long, but it bends toward justice"
> >> > -MLK Jr.
> >> >
> >> > _______________________________________________
> >> > netcdfgroup mailing list
> >> > netcdfgroup@xxxxxxxxxxxxxxxx
> >> > For list information or to unsubscribe, visit:
> >> > http://www.unidata.ucar.edu/m
> >> > ailing_lists/
> >
> >
> >
> >
> > --
> > Taylor Binnington
> > e. tbinnington@xxxxxxxxx
> > c. 647 926 4144
> >
> >
> > _______________________________________________
> > netcdfgroup mailing list
> > netcdfgroup@xxxxxxxxxxxxxxxx
> > For list information or to unsubscribe, visit:
> > http://www.unidata.ucar.edu/mailing_lists/
>
>
>
> --
> David W. Pierce
> Division of Climate, Atmospheric Science, and Physical Oceanography
> Scripps Institution of Oceanography, La Jolla, California, USA
> (858) 534-8276 (voice) / (858) 534-8561 (fax) dpierce@xxxxxxxx
>
--
Taylor Binnington
e. tbinnington@xxxxxxxxx
c. 647 926 4144
