def test_as_cartopy_projection(self):
latitude_of_projection_origin = -90.0
longitude_of_projection_origin = -45.0
false_easting = 100.0
false_northing = 200.0
ellipsoid = GeogCS(6377563.396, 6356256.909)
st = Stereographic(
central_lat=latitude_of_projection_origin,
central_lon=longitude_of_projection_origin,
false_easting=false_easting,
false_northing=false_northing,
ellipsoid=ellipsoid,
)
expected = ccrs.Stereographic(
central_latitude=latitude_of_projection_origin,
central_longitude=longitude_of_projection_origin,
false_easting=false_easting,
false_northing=false_northing,
globe=ccrs.Globe(
semimajor_axis=6377563.396,
semiminor_axis=6356256.909,
ellipse=None,
),
)
res = st.as_cartopy_projection()
self.assertEqual(res, expected)
def test_optional_args_None(self):
# Check expected defaults with optional args=None.
crs = Stereographic(0,
0,
false_easting=None,
false_northing=None,
true_scale_lat=None)
self._check_crs_defaults(crs)
def stereo():
return Stereographic(
central_lat=-90,
central_lon=-45,
false_easting=100,
false_northing=200,
ellipsoid=GeogCS(6377563.396, 6356256.909),
)
def test_set_optional_args(self):
# Check that setting the optional (non-ellipse) args works.
crs = Stereographic(0,
0,
false_easting=100,
false_northing=-203.7,
true_scale_lat=77)
self.assertEqualAndKind(crs.false_easting, 100.0)
self.assertEqualAndKind(crs.false_northing, -203.7)
self.assertEqualAndKind(crs.true_scale_lat, 77.0)
def _stereo_cube(self, ellipsoid=None):
data = np.arange(12).reshape(3, 4)
cube = Cube(data, 'air_pressure_anomaly')
stereo = Stereographic(-10.0, 20.0, 500000.0, -200000.0, None,
ellipsoid)
coord = DimCoord(np.arange(3), 'projection_y_coordinate', units='m',
coord_system=stereo)
cube.add_dim_coord(coord, 0)
coord = DimCoord(np.arange(4), 'projection_x_coordinate', units='m',
coord_system=stereo)
cube.add_dim_coord(coord, 1)
return cube
def test_as_cartopy_projection(self):
latitude_of_projection_origin=-90.0
longitude_of_projection_origin=-45.0
false_easting=100.0
false_northing=200.0
ellipsoid=GeogCS(6377563.396, 6356256.909)
st = Stereographic(central_lat=latitude_of_projection_origin,
central_lon=longitude_of_projection_origin,
false_easting=false_easting,
false_northing=false_northing,
ellipsoid=ellipsoid)
expected = ccrs.Stereographic(
central_latitude=latitude_of_projection_origin,
central_longitude=longitude_of_projection_origin,
false_easting=false_easting,
false_northing=false_northing,
globe=ccrs.Globe(semimajor_axis=6377563.396,
semiminor_axis=6356256.909, ellipse=None))
res = st.as_cartopy_projection()
self.assertEqual(res, expected)
def test_valid(self):
cf_grid_var = mock.Mock(spec=[],
latitude_of_projection_origin=0,
longitude_of_projection_origin=0,
false_easting=-100,
false_northing=200,
scale_factor_at_projection_origin=1,
semi_major_axis=6377563.396,
semi_minor_axis=6356256.909)
cs = build_stereographic_coordinate_system(None, cf_grid_var)
expected = Stereographic(
central_lat=cf_grid_var.latitude_of_projection_origin,
central_lon=cf_grid_var.longitude_of_projection_origin,
false_easting=cf_grid_var.false_easting,
false_northing=cf_grid_var.false_northing,
ellipsoid=iris.coord_systems.GeogCS(cf_grid_var.semi_major_axis,
cf_grid_var.semi_minor_axis))
self.assertEqual(cs, expected)
def _stereo_cube(self, ellipsoid=None):
data = self.array_lib.arange(12).reshape(3, 4)
cube = Cube(data, "air_pressure_anomaly")
stereo = Stereographic(-10.0, 20.0, 500000.0, -200000.0, None,
ellipsoid)
coord = DimCoord(
np.arange(3),
"projection_y_coordinate",
units="m",
coord_system=stereo,
)
cube.add_dim_coord(coord, 0)
coord = DimCoord(
np.arange(4),
"projection_x_coordinate",
units="m",
coord_system=stereo,
)
cube.add_dim_coord(coord, 1)
return cube
def _test(self, inverse_flattening=False, no_offsets=False):
test_easting = -100
test_northing = 200
gridvar_props = dict(
latitude_of_projection_origin=0,
longitude_of_projection_origin=0,
false_easting=test_easting,
false_northing=test_northing,
scale_factor_at_projection_origin=1,
semi_major_axis=6377563.396,
)
if inverse_flattening:
gridvar_props["inverse_flattening"] = 299.3249646
expected_ellipsoid = iris.coord_systems.GeogCS(
6377563.396, inverse_flattening=299.3249646)
else:
gridvar_props["semi_minor_axis"] = 6356256.909
expected_ellipsoid = iris.coord_systems.GeogCS(
6377563.396, 6356256.909)
if no_offsets:
del gridvar_props["false_easting"]
del gridvar_props["false_northing"]
test_easting = 0
test_northing = 0
cf_grid_var = mock.Mock(spec=[], **gridvar_props)
cs = build_stereographic_coordinate_system(None, cf_grid_var)
expected = Stereographic(
central_lat=cf_grid_var.latitude_of_projection_origin,
central_lon=cf_grid_var.longitude_of_projection_origin,
false_easting=test_easting,
false_northing=test_northing,
ellipsoid=expected_ellipsoid,
)
self.assertEqual(cs, expected)
def test_no_optional_args(self):
# Check expected defaults with no optional args.
crs = Stereographic(0, 0)
self._check_crs_defaults(crs)
