operation_from_geogtran¶

geodetic_engine.persistablereference.operation_from_geogtran(wkt)[source]¶

Build the coordinate operation an ESRI GEOGTRAN states.

ESRI’s GEOGTRAN is not standard WKT and PROJ will not read one, so its parameters are translated here exactly as they are inside a persistableReference, which is this same definition in a JSON envelope. Use it when a register hands over the transformation on its own.

Parameters:

wkt (str) – The GEOGTRAN, without an envelope around it.

Return type:

CoordinateOperation

Returns:

The operation, ready to be applied or bound to a CRS.

Raises:

MalformedReferenceError – If the WKT cannot be read, or states something other than a GEOGTRAN.
UnsupportedReferenceError – If it states a vertical transformation.
UnsupportedMethodError – If it states a method or parameter this package will not translate.
UnresolvableGridError – If a grid-based step names a dataset that resolves to no single grid in PROJ’s database.

Example

>>> ed50 = (
...     'GEOGCS["GCS_European_1950",DATUM["D_European_1950",'
...     'SPHEROID["International_1924",6378388.0,297.0]],'
...     'PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]]'
... )
>>> wgs84 = (
...     'GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",'
...     'SPHEROID["WGS_1984",6378137.0,298.257223563]],'
...     'PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]]'
... )
>>> operation = operation_from_geogtran(
...     f'GEOGTRAN["ED_1950_To_WGS_1984_1",{ed50},{wgs84},'
...     'METHOD["Geocentric_Translation"],'
...     'PARAMETER["X_Axis_Translation",-87.0],'
...     'PARAMETER["Y_Axis_Translation",-98.0],'
...     'PARAMETER["Z_Axis_Translation",-121.0]]'
... )
>>> operation.method_name
'Geocentric translations (geog2D domain)'
>>> [p.value for p in operation.params]
[-87.0, -98.0, -121.0]