NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
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NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
For the opendap access case, drop the .nc suffix.
--
Christopher Lynnes, NASA/GSFC
301-614-5185
________________________________________
From: Taylor Binnington [tbinnington@xxxxxxxxx]
Sent: Tuesday, January 08, 2013 12:46 PM
To: Lynnes, Christopher S. (GSFC-6102); Roy Mendelssohn - NOAA Federal;
netcdfgroup
Subject: Re: [netcdfgroup] Segmentation fault on NcFile open
Thank you Roy and Christopher.
I am now able to successfully open a local file *.nc, which I generated using
the FTP subsetter, with the netcdf 4.2.1 C++ libraries via:
NcFile
dataFile("MERRA100.prod.assim.inst3_3d_asm_Cp.19790101.SUB.nc<http://MERRA100.prod.assim.inst3_3d_asm_Cp.19790101.SUB.nc>",NcFile::ReadOnly);
I can not, however, open a file through OPeNDAP with .nc appended to the .hdf
file name, via:
NcFile
dataFile("http://goldsmr3.sci.gsfc.nasa.gov/opendap/MERRA/MAI3CPASM.5.2.0/1979/01/MERRA100.prod.assim.inst3_3d_asm_Cp.19790101.hdf.nc",NcFile::ReadOnly);
since the method
dataFile.is_valid()
returns false. I have not yet attempted to open this file locally (meaning, not
accessing it through OPeNDAP) since, as you say Chris, it's very large and my
connection is quite limited.
Roy, I was confused by your comment:
>"If you had gotten it from opendap, then it wouldn't be an hdf file.
>Moreover, there is the option to access the OpeNDAP server directly from the
>NetCDF library, which is what people have been trying to tell you."
Yet looking at an OPeNDAP directory
(http://goldsmr2.sci.gsfc.nasa.gov/opendap/MERRA/MAT1NXSLV.5.2.0/1979/01/contents.html),
each file appears to be an HDF file.
At first, I had been attempting to open a sample file, using:
NcFile
DataFile("http://goldsmr3.sci.gsfc.nasa.gov/opendap/MERRA/MAI3CPASM.5.2.0/2012/01/MERRA300.prod.assim.inst3_3d_asm_Cp.20120101.hdf";,
NcFile::ReadOnly);
...but now I understand (among many other things) that I should not be able to
open such a file, since it is really an HDF-EOS, which are not natively
compatible with NetCDF.
Thank you for all of your help (very appreciated!). I will experiment on my own
for a bit and post future questions under a more relevant thread title, since I
consider my segmentation fault issue solved.
--
Taylor Binnington
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