Fix float precision in csv writing

Author: RichardHitier

speasy/core/codecs/bundled_codecs/hapi_csv/writer.py

@@ -35,7 +35,7 @@ def _to_csv(hapi_csv_file: HapiCsvFile, dest:io.IOBase, with_headers=True) -> bo
                 data[f"{param.name}_{i}"] = vals[:, i]
 
     df = pds.DataFrame(data)
-    df.to_csv(dest, index=False, header=False, date_format='%Y-%m-%dT%H:%M:%S.%fZ', float_format='%.3g')
+    df.to_csv(dest, index=False, header=False, date_format='%Y-%m-%dT%H:%M:%S.%fZ', float_format='%.7g')
     return True
 
 

tests/test_hapi_codecs.py

@@ -189,3 +189,17 @@ def test_hapi_csv_compliant_headers(self):
                 headers = _extract_headers(f)
                 for key in ["HAPI", "startDate", "stopDate", "format", "status", "parameters"]:
                     self.assertIn(key, headers)
+
+    def test_hapi_csv_precision(self):
+        hapi_csv_codec: CodecInterface = get_codec('hapi/csv')
+        imf_data = spz.get_data(
+            spz.inventories.tree.amda.Parameters.ACE.MFI.ace_imf_all.imf,
+            "2008-01-01",
+            "2008-01-02",
+        )
+        with tempfile.NamedTemporaryFile(suffix='.csv', delete=True) as tmp:
+            hapi_csv_codec.save_variables(variables=[imf_data], file=tmp)
+            df = pd.read_csv(tmp.name, comment='#', sep=',', header=None, skiprows=0, parse_dates=[0], index_col=0)
+            self.assertAlmostEqual(float(df.iloc[0, 0]), float(imf_data.values[0, 0]), places=3)
+            self.assertAlmostEqual(float(df.iloc[0, 1]), float(imf_data.values[0, 1]), places=3)
+            self.assertAlmostEqual(float(df.iloc[0, 2]), float(imf_data.values[0, 2]), places=3)