def clip_box(self, minx, miny, maxx, maxy, auto_expand=False, auto_expand_limit=3):
"""Clip the :class:`xarray.DataArray` by a bounding box.
Parameters
----------
minx: float
Minimum bound for x coordinate.
miny: float
Minimum bound for y coordinate.
maxx: float
Maximum bound for x coordinate.
maxy: float
Maximum bound for y coordinate.
auto_expand: bool
If True, it will expand clip search if only 1D raster found with clip.
auto_expand_limit: int
maximum number of times the clip will be retried before raising
an exception.
Returns
-------
DataArray: A clipped :class:`xarray.DataArray` object.
"""
if self.width == 1 or self.height == 1:
raise OneDimensionalRaster(
"At least one of the raster x,y coordinates has only one point."
)
resolution_x, resolution_y = self.resolution()
clip_minx = minx - abs(resolution_x) / 2.0
clip_miny = miny - abs(resolution_y) / 2.0
clip_maxx = maxx + abs(resolution_x) / 2.0
clip_maxy = maxy + abs(resolution_y) / 2.0
cl_array = self.slice_xy(clip_minx, clip_miny, clip_maxx, clip_maxy)
if cl_array.rio.width < 1 or cl_array.rio.height < 1:
raise NoDataInBounds("No data found in bounds.")
if cl_array.rio.width == 1 or cl_array.rio.height == 1:
if auto_expand and auto_expand < auto_expand_limit:
return self.clip_box(
clip_minx,
clip_miny,
clip_maxx,
clip_maxy,
auto_expand=int(auto_expand) + 1,
auto_expand_limit=auto_expand_limit,
)
raise OneDimensionalRaster(
"At least one of the clipped raster x,y coordinates"
" has only one point."
)
# make sure correct attributes preserved & projection added
_add_attrs_proj(cl_array, self._obj)
return cl_array
def resolution(self, recalc=False):
"""Determine the resolution of the `xarray.DataArray`
Parameters
----------
recalc: bool, optional
Will force the resolution to be recalculated instead of using the
transform attribute.
"""
if not recalc or self.width == 1 or self.height == 1:
try:
# get resolution from xarray rasterio
data_transform = Affine(*self._obj.attrs["transform"][:6])
resolution_x = data_transform.a
resolution_y = data_transform.e
recalc = False
except KeyError:
recalc = True
if recalc:
left, bottom, right, top = self._internal_bounds()
if self.width == 1 or self.height == 1:
raise OneDimensionalRaster(
"Only 1 dimenional array found. Cannot calculate the resolution."
)
resolution_x = (right - left) / (self.width - 1)
resolution_y = (bottom - top) / (self.height - 1)
return resolution_x, resolution_y
def resolution(self, recalc=False):
"""
Parameters
----------
recalc: bool, optional
Will force the resolution to be recalculated instead of using the
transform attribute.
Returns
-------
x_resolution, y_resolution: float
The resolution of the `xarray.DataArray` | `xarray.Dataset`
"""
transform = self._cached_transform()
if (
not recalc or self.width == 1 or self.height == 1
) and transform is not None:
resolution_x = transform.a
resolution_y = transform.e
return resolution_x, resolution_y
# if the coordinates of the spatial dimensions are missing
# use the cached transform resolution
try:
left, bottom, right, top = self._internal_bounds()
except DimensionMissingCoordinateError:
if transform is None:
raise
resolution_x = transform.a
resolution_y = transform.e
return resolution_x, resolution_y
if self.width == 1 or self.height == 1:
raise OneDimensionalRaster(
"Only 1 dimenional array found. Cannot calculate the resolution."
f"{_get_data_var_message(self._obj)}"
)
resolution_x = (right - left) / (self.width - 1)
resolution_y = (bottom - top) / (self.height - 1)
return resolution_x, resolution_y
def clip_box(self,
minx,
miny,
maxx,
maxy,
auto_expand=False,
auto_expand_limit=3):
"""Clip the :obj:`xarray.DataArray` by a bounding box.
Parameters
----------
minx: float
Minimum bound for x coordinate.
miny: float
Minimum bound for y coordinate.
maxx: float
Maximum bound for x coordinate.
maxy: float
Maximum bound for y coordinate.
auto_expand: bool
If True, it will expand clip search if only 1D raster found with clip.
auto_expand_limit: int
maximum number of times the clip will be retried before raising
an exception.
Returns
-------
:obj:`xarray.DataArray`:
The clipped object.
"""
if self.width == 1 or self.height == 1:
raise OneDimensionalRaster(
"At least one of the raster x,y coordinates has only one point."
f"{_get_data_var_message(self._obj)}")
# make sure that if the coordinates are
# in reverse order that it still works
resolution_x, resolution_y = self.resolution()
if resolution_y < 0:
top = maxy
bottom = miny
else:
top = miny
bottom = maxy
if resolution_x < 0:
left = maxx
right = minx
else:
left = minx
right = maxx
# pull the data out
window = rasterio.windows.from_bounds(
left=np.array(left).item(),
bottom=np.array(bottom).item(),
right=np.array(right).item(),
top=np.array(top).item(),
transform=self.transform(recalc=True),
width=self.width,
height=self.height,
)
cl_array = self.isel_window(window)
# check that the window has data in it
if cl_array.rio.width <= 1 or cl_array.rio.height <= 1:
if auto_expand and auto_expand < auto_expand_limit:
resolution_x, resolution_y = self.resolution()
return self.clip_box(
minx=minx - abs(resolution_x) / 2.0,
miny=miny - abs(resolution_y) / 2.0,
maxx=maxx + abs(resolution_x) / 2.0,
maxy=maxy + abs(resolution_y) / 2.0,
auto_expand=int(auto_expand) + 1,
auto_expand_limit=auto_expand_limit,
)
if cl_array.rio.width < 1 or cl_array.rio.height < 1:
raise NoDataInBounds(
f"No data found in bounds.{_get_data_var_message(self._obj)}"
)
if cl_array.rio.width == 1 or cl_array.rio.height == 1:
raise OneDimensionalRaster(
"At least one of the clipped raster x,y coordinates"
" has only one point."
f"{_get_data_var_message(self._obj)}")
# make sure correct attributes preserved & projection added
_add_attrs_proj(cl_array, self._obj)
return cl_array
