def test_from_cf_transverse_mercator(towgs84_test):
crs = CRS.from_cf({
"grid_mapping_name": "transverse_mercator",
"latitude_of_projection_origin": 0,
"longitude_of_central_meridian": 15,
"false_easting": 2520000,
"false_northing": 0,
"reference_ellipsoid_name": "intl",
"towgs84": towgs84_test,
"unit": "m",
})
expected_cf = {
"semi_major_axis": 6378388.0,
"semi_minor_axis": crs.ellipsoid.semi_minor_metre,
"inverse_flattening": 297.0,
"reference_ellipsoid_name": "International 1909 (Hayford)",
"longitude_of_prime_meridian": 0.0,
"prime_meridian_name": "Greenwich",
"grid_mapping_name": "transverse_mercator",
"latitude_of_projection_origin": 0.0,
"longitude_of_central_meridian": 15.0,
"false_easting": 2520000.0,
"false_northing": 0.0,
"scale_factor_at_central_meridian": 1.0,
}
cf_dict = crs.to_cf()
assert cf_dict.pop("crs_wkt").startswith("BOUNDCRS[")
assert_almost_equal(cf_dict.pop("towgs84"),
_try_list_if_string(towgs84_test))
assert cf_dict == expected_cf
# test roundtrip
expected_cf["towgs84"] = _try_list_if_string(towgs84_test)
_test_roundtrip(expected_cf, "BOUNDCRS[")
def parse(val):
if val.lower() == "true":
return True
elif val.lower() == "false":
return False
try:
return int(val)
except ValueError:
pass
try:
return float(val)
except ValueError:
pass
return _try_list_if_string(val)
def from_cf(in_cf: dict, errcheck=False) -> "CRS":
"""
.. versionadded:: 2.2.0
This converts a Climate and Forecast (CF) Grid Mapping Version 1.8
dict to a :obj:`pyproj.crs.CRS` object.
.. warning:: Parameters may be lost if a mapping
from the CF parameter is not found. For best results
store the WKT of the projection in the crs_wkt attribute.
Parameters
----------
in_cf: dict
CF version of the projection.
errcheck: bool, optional
This parameter is for backwards compatibility with the old version.
It currently does nothing when True or False.
Returns
-------
CRS
"""
unknown_names = ("unknown", "undefined")
if "crs_wkt" in in_cf:
return CRS(in_cf["crs_wkt"])
elif "spatial_ref" in in_cf: # for previous supported WKT key
return CRS(in_cf["spatial_ref"])
grid_mapping_name = in_cf.get("grid_mapping_name")
if grid_mapping_name is None:
raise CRSError(
"CF projection parameters missing 'grid_mapping_name'")
# build datum if possible
datum = _horizontal_datum_from_params(in_cf)
# build geographic CRS
try:
geographic_conversion_method = _GEOGRAPHIC_GRID_MAPPING_NAME_MAP[
grid_mapping_name] # type: Optional[Callable]
except KeyError:
geographic_conversion_method = None
geographic_crs_name = in_cf.get("geographic_crs_name")
if datum:
geographic_crs = GeographicCRS(
name=geographic_crs_name or "undefined",
datum=datum,
) # type: CRS
elif geographic_crs_name and geographic_crs_name not in unknown_names:
geographic_crs = CRS(geographic_crs_name)
else:
geographic_crs = GeographicCRS()
if grid_mapping_name == "latitude_longitude":
return geographic_crs
if geographic_conversion_method is not None:
return DerivedGeographicCRS(
base_crs=geographic_crs,
conversion=geographic_conversion_method(in_cf),
)
# build projected CRS
try:
conversion_method = _GRID_MAPPING_NAME_MAP[grid_mapping_name]
except KeyError:
raise CRSError(
"Unsupported grid mapping name: {}".format(grid_mapping_name))
projected_crs = ProjectedCRS(
name=in_cf.get("projected_crs_name", "undefined"),
conversion=conversion_method(in_cf),
geodetic_crs=geographic_crs,
)
# build bound CRS if exists
bound_crs = None
if "towgs84" in in_cf:
bound_crs = BoundCRS(
source_crs=projected_crs,
target_crs="WGS 84",
transformation=ToWGS84Transformation(
projected_crs.geodetic_crs,
*_try_list_if_string(in_cf["towgs84"])),
)
if "geopotential_datum_name" not in in_cf:
return bound_crs or projected_crs
# build Vertical CRS
vertical_crs = VerticalCRS(
name="undefined",
datum=in_cf["geopotential_datum_name"],
geoid_model=in_cf.get("geoid_name"),
)
# build compound CRS
return CompoundCRS(
name="undefined",
components=[bound_crs or projected_crs, vertical_crs])
def from_cf(
in_cf: dict,
ellipsoidal_cs: Any = None,
cartesian_cs: Any = None,
vertical_cs: Any = None,
errcheck=False,
) -> "CRS":
"""
.. versionadded:: 2.2.0
.. versionadded:: 3.0.0 ellipsoidal_cs, cartesian_cs, vertical_cs
This converts a Climate and Forecast (CF) Grid Mapping Version 1.8
dict to a :obj:`pyproj.crs.CRS` object.
:ref:`build_crs_cf`
Parameters
----------
in_cf: dict
CF version of the projection.
ellipsoidal_cs: Any, optional
Input to create an Ellipsoidal Coordinate System.
Anything accepted by :meth:`pyproj.crs.CoordinateSystem.from_user_input`
or an Ellipsoidal Coordinate System created from :ref:`coordinate_system`.
cartesian_cs: Any, optional
Input to create a Cartesian Coordinate System.
Anything accepted by :meth:`pyproj.crs.CoordinateSystem.from_user_input`
or :class:`pyproj.crs.coordinate_system.Cartesian2DCS`.
vertical_cs: Any, optional
Input to create a Vertical Coordinate System accepted by
:meth:`pyproj.crs.CoordinateSystem.from_user_input`
or :class:`pyproj.crs.coordinate_system.VerticalCS`
errcheck: bool, optional
This parameter is for backwards compatibility with the old version.
It currently does nothing when True or False.
Returns
-------
CRS
"""
unknown_names = ("unknown", "undefined")
if "crs_wkt" in in_cf:
return CRS(in_cf["crs_wkt"])
elif "spatial_ref" in in_cf: # for previous supported WKT key
return CRS(in_cf["spatial_ref"])
grid_mapping_name = in_cf.get("grid_mapping_name")
if grid_mapping_name is None:
raise CRSError(
"CF projection parameters missing 'grid_mapping_name'")
# build datum if possible
datum = _horizontal_datum_from_params(in_cf)
# build geographic CRS
try:
geographic_conversion_method = _GEOGRAPHIC_GRID_MAPPING_NAME_MAP[
grid_mapping_name] # type: Optional[Callable]
except KeyError:
geographic_conversion_method = None
geographic_crs_name = in_cf.get("geographic_crs_name")
if datum:
geographic_crs = GeographicCRS(
name=geographic_crs_name or "undefined",
datum=datum,
ellipsoidal_cs=ellipsoidal_cs,
) # type: CRS
elif geographic_crs_name and geographic_crs_name not in unknown_names:
geographic_crs = CRS(geographic_crs_name)
if ellipsoidal_cs is not None:
geographic_crs_json = geographic_crs.to_json_dict()
geographic_crs_json[
"coordinate_system"] = CoordinateSystem.from_user_input(
ellipsoidal_cs).to_json_dict()
geographic_crs = CRS(geographic_crs_json)
else:
geographic_crs = GeographicCRS(ellipsoidal_cs=ellipsoidal_cs)
if grid_mapping_name == "latitude_longitude":
return geographic_crs
if geographic_conversion_method is not None:
return DerivedGeographicCRS(
base_crs=geographic_crs,
conversion=geographic_conversion_method(in_cf),
ellipsoidal_cs=ellipsoidal_cs,
)
# build projected CRS
try:
conversion_method = _GRID_MAPPING_NAME_MAP[grid_mapping_name]
except KeyError:
raise CRSError(
f"Unsupported grid mapping name: {grid_mapping_name}")
projected_crs = ProjectedCRS(
name=in_cf.get("projected_crs_name", "undefined"),
conversion=conversion_method(in_cf),
geodetic_crs=geographic_crs,
cartesian_cs=cartesian_cs,
)
# build bound CRS if exists
bound_crs = None
if "towgs84" in in_cf:
bound_crs = BoundCRS(
source_crs=projected_crs,
target_crs="WGS 84",
transformation=ToWGS84Transformation(
projected_crs.geodetic_crs,
*_try_list_if_string(in_cf["towgs84"])),
)
if "geopotential_datum_name" not in in_cf:
return bound_crs or projected_crs
# build Vertical CRS
vertical_crs = VerticalCRS(
name="undefined",
datum=in_cf["geopotential_datum_name"],
geoid_model=in_cf.get("geoid_name"),
vertical_cs=vertical_cs,
)
# build compound CRS
return CompoundCRS(
name="undefined",
components=[bound_crs or projected_crs, vertical_crs])
