def create_variable(dim_sizes, dtype, dim_names=None, attributes=None, fill_value=None):
"""
Return default empty xarray Variable
:type dim_sizes: list
:param dim_sizes: dimension sizes as ints, i.e. [dim1_size, dim2_size, dim3_size] (e.g. [2,3,5])
:type dtype: type
:param dtype: numpy data type
:type dim_names: list
:param dim_names: (optional) dimension names as strings, i.e. ["dim1_name", "dim2_name", "dim3_size"]
:type attributes: dict
:param attributes: (optional) dictionary of variable attributes, e.g. standard_name
:type fill_value: int/float
:param fill_value: (optional) fill value (if None CF compliant value used)
:return: Default empty variable
:rtype: xarray.Variable
"""
if fill_value is None:
fill_value = DatasetUtil.get_default_fill_value(dtype)
default_array = DatasetUtil.create_default_array(dim_sizes, dtype, fill_value=fill_value)
if dim_names is None:
variable = Variable(DEFAULT_DIM_NAMES[-len(dim_sizes):], default_array)
else:
variable = Variable(dim_names, default_array)
variable.attrs["_FillValue"] = fill_value
if attributes is not None:
variable.attrs = {**variable.attrs, **attributes}
return variable
