def test_custom_datum__input():
cd = CustomDatum(
ellipsoid=Ellipsoid.from_epsg(7001),
prime_meridian=PrimeMeridian.from_name("Lisbon"),
)
assert cd.ellipsoid.name == "Airy 1830"
assert cd.prime_meridian.name == "Lisbon"
def test_bound_crs__example():
proj_crs = ProjectedCRS(
conversion=TransverseMercatorConversion(
latitude_natural_origin=0,
longitude_natural_origin=15,
false_easting=2520000,
false_northing=0,
scale_factor_natural_origin=0.9996,
),
geodetic_crs=GeographicCRS(
datum=CustomDatum(ellipsoid="International 1909 (Hayford)")
),
)
bound_crs = BoundCRS(
source_crs=proj_crs,
target_crs="WGS 84",
transformation=ToWGS84Transformation(
proj_crs.geodetic_crs, -122.74, -34.27, -22.83, -1.884, -3.4, -3.03, -15.62
),
)
with pytest.warns(UserWarning):
assert bound_crs.to_dict() == {
"ellps": "intl",
"k": 0.9996,
"lat_0": 0,
"lon_0": 15,
"no_defs": None,
"proj": "tmerc",
"towgs84": [-122.74, -34.27, -22.83, -1.884, -3.4, -3.03, -15.62],
"type": "crs",
"units": "m",
"x_0": 2520000,
"y_0": 0,
}
def _horizontal_datum_from_params(cf_params):
# step 1: build ellipsoid
ellipsoid = None
ellipsoid_name = cf_params.get("reference_ellipsoid_name")
try:
ellipsoid = CustomEllipsoid(
name=ellipsoid_name or "undefined",
semi_major_axis=cf_params.get("semi_major_axis"),
semi_minor_axis=cf_params.get("semi_minor_axis"),
inverse_flattening=cf_params.get("inverse_flattening"),
radius=cf_params.get("earth_radius"),
)
except CRSError:
if ellipsoid_name:
ellipsoid = Ellipsoid.from_name(ellipsoid_name)
# step 2: build prime meridian
prime_meridian = None
prime_meridian_name = cf_params.get("prime_meridian_name")
try:
prime_meridian = CustomPrimeMeridian(
name=prime_meridian_name or "undefined",
longitude=cf_params["longitude_of_prime_meridian"],
)
except KeyError:
if prime_meridian_name:
prime_meridian = PrimeMeridian.from_name(prime_meridian_name)
# step 3: build datum
datum_name = cf_params.get("horizontal_datum_name")
if ellipsoid or prime_meridian:
return CustomDatum(
name=datum_name or "undefined",
ellipsoid=ellipsoid or "WGS 84",
prime_meridian=prime_meridian or "Greenwich",
)
if datum_name:
return Datum.from_name(datum_name)
return None
def test_custom_datum():
cd = CustomDatum()
assert cd.ellipsoid.name == "WGS 84"
assert cd.prime_meridian.name == "Greenwich"
