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Ghansham, If you are using NetCDF-4, you may have any number of unlimited time dimensions. Thus, in your example below, you should be able to create a single NetCDF-4 file with three sets of lat/lon dimensions, three time dimensions, and your data. More on NetCDF dimensions here in this documentation: http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/Dimensions.html Regards, Lansing Madry Unidata Boulder, Colorado > Another query related to point datasets that came to my mind when you > talked about rosetta. I have 3 ascii files that have satellite derived > winds data from 3 channels (ir, wv and vis). The locations of observations > in three files are disjoint. Can we write all of them into a single nc > file. There will be three different sets of lat/ lon variables for > respective channels. And you can expect 3 different sets of time varianles > as number of observations will vary for each channel. I hope I am clear in > communicating. I eant them in single file as they from the same time > imagery. > Ghansham > > address@hidden> wrote: > > Hi Ghansham, > > > > In NcML, you can use the <values> tag inside a variable to set the > values. If > > you want to point the NcML to an external dataset, you will need to write > an > > IOSP to enable netCDF-Java to read the file. > > > > netCDF has a utility called ncgen, which creates a netCDF file from a CDL > file: > > > > > > http://www.unidata.ucar.edu/software/netcdf/docs/ncgen-man-1.html > > > > CDL files are not xml, but they are simple none-the-less: > > > > http://www.unidata.ucar.edu/software/netcdf/docs/ncgen-man-1.html#EXAMPLES > > > > You would still need to write a program to read in your ascii or binary > data to write > > the CDL file, but at that point you might as well just write out a netCDF > object using > > the netCDF C or Java API. > > > > Sean > > > > PS: Rosetta is a very new project that is still in active development. It > can currently > > convert ASCII data from station baseed sites into CF 1.6 compliant > netCDF files, but > > this is certainly only the first step for the project. > > > >> Can you put up a sample program along with dataset. Here are a few things > >> to consider. NcML always refers to a dataset. Can it refer to binary data > >> on disk and read it to create a variable within the file. I hope I am not > >> confusing you. I have set of binary and ascii files which I want to write > >> into netcdf-4 using ncml. I am afraid if that is possible. Rosetta is > >> trying to do it for CSV files. I will send you a sample xml file what I > >> take as input to write hdf-5 file. > >> > >> Long time back hdf5 used to have a utility called h5gen which used to > take > >> xml input to generate hdf5. But they have discontinued it. God knows the > >> reason. They are switching from XML to JSON based approach as that is too > >> portable and very hot topic as far as web is concerned. > >> FYI, JSON has a new incarnation for binary data in the form BSON (binary > >> JSON). http://bsonspec.org/ > >> > >> > >> > >> > >> regards > >> Ghansham > >> > >> > >> address@hidden> wrote: > >> > >> > Greetings Ghansham, > >> > > >> > Yes, you can convert NcML to a netCDF file using netCDF-Java. See > >> > > >> > http://www.unidata.ucar.edu/software/netcdf/ncml/ > >> > > >> > for more details (look for "Using NcML to create a NetCDF-3 file"). > >> > The link above uses ucar.nc2.FileWriter, which is deprecated, but > >> > should still work if you are looking for something quick. > >> > > >> > That said, I would recommend using > >> > > >> > ucar.nc2.FileWriter2 > >> > > >> > ( > >> > > www.unidata.ucar.edu/software/netcdf-java/v4.3/javadoc/ucar/nc2/FileWriter2.html > >> > ) > >> > > >> > and, if you have the C library of netCDF installed, you can directly > write > >> > out a > >> > netCDF-4 file, thus skipping the conversion using NCO. > >> > > >> > See the first link for more info on the structure of NcML. > >> > > >> > Cheers, > >> > > >> > Sean > >> > > >> > > R/Sir > >> > > > >> > > > >> > > Is there a way to convert raw data to netcdf using XML. > >> > > > >> > > I read somewhere: > >> > > > >> > > > >> > > http://hdf-forum.184993.n3.nabble.com/h5gen-or-any-h5dump-generated-XML-to-HDF5-td3719793.html > >> > > > >> > > See post by H. Joe Lee.... > >> > > It states something like this: > >> > > Create NcML file (a variant of XML) and use NetCDF-Java to generate > an > >> > > NetCDF-3 file [1]. > >> > > Then convert the NetCDF-3 to NetCDF-4 using NCO [2]. > >> > > > >> > > The converted NetCDF-4 file is HDF5 file. > >> > > You got the HDF5 from XML (NcML). > >> > > > >> > > > >> > > > >> > > Ghansham > >> > > > >> > > > >> > > >> > Ticket Details > >> > =================== > >> > Ticket ID: SBB-665470 > >> > Department: Support netCDF Java > >> > Priority: Normal > >> > Status: Open > >> > > >> > > >> > >> > > > > Ticket Details > > =================== > > Ticket ID: SBB-665470 > > Department: Support netCDF Java > > Priority: Normal > > Status: Open > > > > > > Ticket Details =================== Ticket ID: SBB-665470 Department: Support netCDF Java Priority: Normal Status: Open