Documentation

netcdf.defVar

Create NetCDF variable

Syntax

varid = netcdf.defVar(ncid,varname,xtype,dimids)

Description

varid = netcdf.defVar(ncid,varname,xtype,dimids) creates a new variable in the dataset identified by ncid.

varname is a character string that specifies the name of the variable.

xtype specifies the NetCDF data type of the variable, using one of the following strings.

Value of xtypeMATLAB® Class
'NC_BYTE'int8 or uint8[a]
'NC_CHAR'char
'NC_SHORT'int16
'NC_INT'int32
'NC_FLOAT'single
'NC_DOUBLE'double

[a] NetCDF interprets byte data as either signed or unsigned.

Alternatively, xtype can be the numeric equivalent returned by the netcdf.getConstant function.

dimids specifies a list of dimension IDs.

netcdf.defVar returns varid, a numeric identifier for the new variable.

This function corresponds to the nc_def_var function in the NetCDF library C API. Because MATLAB uses FORTRAN-style ordering, the fastest-varying dimension comes first and the slowest comes last. Any unlimited dimension is therefore last in the list of dimension IDs. This ordering is the reverse of that found in the C API.To use this function, you should be familiar with the NetCDF programming paradigm. See netcdf for more information.

Examples

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Define Dimension and Variable in NetCDF File

Create a new NetCDF file, define a dimension in the file, and then define a variable on that dimension. In NetCDF files, you must create a dimension before you can create a variable. To run this example, you must have write permission in your current folder.

Create a new NetCDF file named foo.nc.

ncid = netcdf.create('foo.nc','NC_NOCLOBBER');

Define a dimension in the new file.

dimid = netcdf.defDim(ncid,'x',50);

Define a variable in the new file using netcdf.defVar.

varid = netcdf.defVar(ncid,'myvar','double',dimid)
varid =

     0

netcdf.defVar returns a numeric identifier for the new variable.

Close the file.

netcdf.close(ncid)
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