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Hi Yoann, > I am dealing with netcdf ostia SST global product, and since the data are > consuming a lot of space in my hard drive, > I was wondering how to extract of the global file just the portion of > territory which I am interested in. > I amusing Matlab and SNC TOOL and MEXNC tools. > but I just can t find the way to do that with this tools. So I am open to > other tools if they are more efficient or whatever. > could you please help me, if you know a solution; The NCO software, and in particular the ncks utility, is useful for extracting subsets of a netCDF data file and writing a new file containing just the subset. See: http://www.unidata.ucar.edu/software/netcdf/software.html#NCO for a description and links to NCO software. Note that NCO is not developed or supported by Unidata, so if you have questions, you will need to use the sourceforge support forum for NCO. Other utilities that may also be useful for the problem you describe include NCL and CDO, described here: http://www.unidata.ucar.edu/software/netcdf/software.html#NCL http://www.unidata.ucar.edu/software/netcdf/software.html#CDO If the data you are using is available remotely on a server via the OPeNDAP protocols, then you can access just a single variable, such as SST, from the file by using a URL instead of the filename to open the file, appending "?SST" to the URL to just access the variable named "SST". If the data is available from a TDS server, you can use the experimental netCDF subset service to access just the part of the grid within a specified latitude- longitude bounding box, as described here: http://www.unidata.ucar.edu/projects/THREDDS/tech/interfaceSpec/NetcdfSubsetService.html Services provide with other servers, for example FERRET or GDS, can provide a similar service: http://www.unidata.ucar.edu/software/netcdf/software.html#FERRET http://grads.iges.org/grads/gds/index.html Finally, you can write a program that uses the netCDF library to read the data file and write a new data file containing only the subset in which you are interested. MATLAB supports use of the netCDF Java interface, which can be used for such programs, as described here: http://sourceforge.net/apps/trac/njtbx --Russ --Russ --Russ --Russ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: MYT-239963 Department: Support netCDF Priority: Normal Status: Closed