Method prepare_variable

xarray/backends/netCDF4_.py:626–671

(
        self, name, variable: Variable, check_encoding=False, unlimited_dims=None
    )

        return variable

    def prepare_variable(
        self, name, variable: Variable, check_encoding=False, unlimited_dims=None
    ):
        _ensure_no_forward_slash_in_name(name)
        attrs = variable.attrs.copy()
        fill_value = attrs.pop("_FillValue", None)
        datatype: np.dtype | ncEnumType | h5EnumType
        datatype = _get_datatype(
            variable, self.format, raise_on_invalid_encoding=check_encoding
        )
        # check enum metadata and use netCDF4.EnumType
        if (
            (meta := np.dtype(datatype).metadata)
            and (e_name := meta.get("enum_name"))
            and (e_dict := meta.get("enum"))
        ):
            datatype = _build_and_get_enum(self, name, datatype, e_name, e_dict)
        encoding = _extract_nc4_variable_encoding(
            variable, raise_on_invalid=check_encoding, unlimited_dims=unlimited_dims
        )
        if name in self.ds.variables:
            nc4_var = self.ds.variables[name]
        else:
            default_args = dict(
                varname=name,
                datatype=datatype,
                dimensions=variable.dims,
                zlib=False,
                complevel=4,
                shuffle=True,
                fletcher32=False,
                contiguous=False,
                chunksizes=None,
                endian="native",
                least_significant_digit=None,
                fill_value=fill_value,
            )
            default_args.update(encoding)
            default_args.pop("_FillValue", None)
            nc4_var = self.ds.createVariable(**default_args)

        nc4_var.setncatts(attrs)

        target = NetCDF4ArrayWrapper(name, self)

        return target, variable.data

    def sync(self):
        self.ds.sync()