def isel_bc(da: xr.DataArray, idx, dim, boundary='wrap'):
"""Select points along axis with ghosting given by a boundary condition
"""
n = da.shape[da.get_axis_num(dim)]
if isinstance(idx, slice):
if idx.stop is None:
idx = slice(idx.start, n, idx.step)
idx = _slice_to_range(idx)
elif not isinstance(idx, Iterable):
idx = [idx]
idx = np.asarray(idx)
if boundary == 'wrap':
idx = idx % n
return da.isel(**{dim: idx})
elif boundary == 'extrap':
idx[idx < 0] = 0
idx[idx >= n] = n-1
return da.isel(**{dim: idx})
else:
raise ValueError("Received unknown boundary condition value")
return da.isel(**{dim: idx})
def arrays_w_tuples():
da = xr.DataArray(
np.random.random((3, 21, 4)),
coords={"time": pd.date_range("2000-01-01", freq="1D", periods=21)},
dims=("a", "time", "x"),
)
arrays = [
da.isel(time=range(0, 18)),
da.isel(time=range(2, 20)).rolling(time=3, center=True).mean(),
xr.DataArray([[1, 2], [1, np.nan]], dims=["x", "time"]),
xr.DataArray([[1, 2], [np.nan, np.nan]], dims=["x", "time"]),
]
array_tuples = [
(arrays[0], arrays[0]),
(arrays[0], arrays[1]),
(arrays[1], arrays[1]),
(arrays[2], arrays[2]),
(arrays[2], arrays[3]),
(arrays[3], arrays[3]),
]
return arrays, array_tuples
def test_datetime_to_numeric_cftime():
times = xr.cftime_range('2000', periods=5, freq='7D')
da = xr.DataArray(times, coords=[times], dims=['time'])
result = utils.datetime_to_numeric(da, datetime_unit='h')
expected = 24 * xr.DataArray(np.arange(0, 35, 7), coords=da.coords)
assert_identical(result, expected)
offset = da.isel(time=1)
result = utils.datetime_to_numeric(da, offset=offset, datetime_unit='h')
expected = 24 * xr.DataArray(np.arange(-7, 28, 7), coords=da.coords)
assert_identical(result, expected)
dtype = np.float32
result = utils.datetime_to_numeric(da, datetime_unit='h', dtype=dtype)
expected = 24 * xr.DataArray(
np.arange(0, 35, 7), coords=da.coords).astype(dtype)
assert_identical(result, expected)