simplify wkb conversion

Author: emanuel-schmid

climada/entity/exposures/base.py

@@ -1132,10 +1132,8 @@ def write_hdf5(self, file_name):
         """
         LOGGER.info("Writing %s", file_name)
         store = pd.HDFStore(file_name, mode="w")
-        pandas_df = pd.DataFrame(self.gdf)
         geocols = self.gdf.columns[self.gdf.dtypes == "geometry"].to_list()
-        for col in geocols:
-            pandas_df[col] = gpd.GeoSeries(pandas_df[col]).to_wkb()
+        pandas_df = self.data.to_wkb()
 
         # Avoid pandas PerformanceWarning when writing HDF5 data
         with warnings.catch_warnings():

climada/entity/exposures/test/test_base.py

@@ -384,6 +384,9 @@ def test_io_hdf5_pass(self):
         exp.ref_year = 2020
         exp.value_unit = "XSD"
 
+        # add another geometry column
+        exp.data["geocol2"] = exp.data.geometry.copy(deep=True)
+
         file_name = DATA_DIR.joinpath("test_hdf5_exp.h5")
 
         # pd.errors.PerformanceWarning should be suppressed. Therefore, make sure that
@@ -431,7 +434,12 @@ def test_io_hdf5_pass(self):
             u_coord.equal_crs(exp.crs, exp_read.crs),
             f"{exp.crs} and {exp_read.crs} are different",
         )
-        self.assertTrue(u_coord.equal_crs(exp.gdf.crs, exp_read.gdf.crs))
+        self.assertTrue(u_coord.equal_crs(exp.data.crs, exp_read.data.crs))
+
+        self.assertTrue(exp_read.data["geocol2"].dtype == "geometry")
+        np.testing.assert_array_equal(
+            exp.data["geocol2"].geometry, exp_read.data["geocol2"].values
+        )
 
 
 class TestAddSea(unittest.TestCase):