def test_from_variables_index_adapter(self) -> None:
# test index type is preserved when variable wraps a pd.Index
data = pd.Series(["foo", "bar"], dtype="category")
pd_idx = pd.Index(data)
var = xr.Variable("x", pd_idx)
index = PandasIndex.from_variables({"x": var})
assert isinstance(index.index, pd.CategoricalIndex)
def test_from_variables(self):
var = xr.Variable("x", [1, 2, 3],
attrs={"unit": "m"},
encoding={"dtype": np.int32})
index, index_vars = PandasIndex.from_variables({"x": var})
xr.testing.assert_identical(var.to_index_variable(), index_vars["x"])
assert index.dim == "x"
assert index.index.equals(index_vars["x"].to_index())
var2 = xr.Variable(("x", "y"), [[1, 2, 3], [4, 5, 6]])
with pytest.raises(ValueError, match=r".*only accepts one variable.*"):
PandasIndex.from_variables({"x": var, "foo": var2})
with pytest.raises(ValueError,
match=r".*only accepts a 1-dimensional variable.*"):
PandasIndex.from_variables({"foo": var2})
def test_from_variables(self) -> None:
# pandas has only Float64Index but variable dtype should be preserved
data = np.array([1.1, 2.2, 3.3], dtype=np.float32)
var = xr.Variable("x",
data,
attrs={"unit": "m"},
encoding={"dtype": np.float64})
index = PandasIndex.from_variables({"x": var})
assert index.dim == "x"
assert index.index.equals(pd.Index(data))
assert index.coord_dtype == data.dtype
var2 = xr.Variable(("x", "y"), [[1, 2, 3], [4, 5, 6]])
with pytest.raises(ValueError, match=r".*only accepts one variable.*"):
PandasIndex.from_variables({"x": var, "foo": var2})
with pytest.raises(ValueError,
match=r".*only accepts a 1-dimensional variable.*"):
PandasIndex.from_variables({"foo": var2})