problem reading netcdf file with readGDAL: "no bands in dataset"
See this page for more information about the GDAL approach to NetCDF: http://www.gdal.org/frmt_netcdf.html If you can construct the subdataset name correctly then readGDAL should be able to return the given variable, as a single band SpatialGridDataFrame.
On Thu, Nov 26, 2009 at 7:27 AM, Michael Sumner <mdsumner at gmail.com> wrote:
There are a number of reasons why GDAL might not be able to read data from NetCDF, although it might appear to get some metadata upfront. The 512x512 thing is a default, and to me means that there are multiple variables in the file, and GDAL requires direct reference to only one of them as a "subdataset". The syntax is something like this: NETCDF:"/path/to/filename.nc":varname If you use gdalinfo at the command line it will tell you the subdataset strings you can use - the rgdal bindings don't reconstruct the output that that utility gives you. Cheers, Mike. On Thu, Nov 26, 2009 at 12:34 AM, ElenaC <E.Couce.07 at bristol.ac.uk> wrote:
Hi all, I'm trying to open a netcdf file using the rgdal library, but readGDAL and GDALinfo don't seem to be able to correctly access the information in the file. It is probably a stupid mistake because I don't understand what I'm doing, but I have already spent a long time trying to sort it out and I could really use some help with it. When I try readGDAL, it fails with the error that there are "no bands in dataset". This is the output I get from GDALinfo:
GDALinfo(fname)
rows ? ? ? ?512 columns ? ? 512 bands ? ? ? 0 origin.x ? ? ? ?0 origin.y ? ? ? ?1 res.x ? ? ? 1 res.y ? ? ? 1 oblique.x ? 0 oblique.y ? 0 driver ? ? ?netCDF projection ?NA Warning messages: 1: In dim(x) : no bands in dataset 2: In GDALinfo(fname) : no bands in dataset But from opening the file with Panoply, it seems it actually contains four variables, two of them 360*180 matrices with the geographical info I'm trying to access (global data with 1 degree spatial resolution), and the two others called "lat" and "lon" with the latitude and longitude values. I don't understand why GDALinfo is telling me that the file has 512 rows and 512 columns and that there are "no bands". What can I do to access the variables I want? Any help would be greatly appreciated! Elena -- View this message in context: http://n2.nabble.com/problem-reading-netcdf-file-with-readGDAL-no-bands-in-dataset-tp4064987p4064987.html Sent from the R-sig-geo mailing list archive at Nabble.com.
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