Update CF aggregation keywords

Changelog.rst

@@ -3,6 +3,8 @@ version NEXTVERSION
 
 **2025-??-??**
 
+* Update CF aggregation keywords
+  (https://github.com/NCAS-CMS/cf-python/issues/868)
 * New keyword parameter to `cf.DimensionCoordinate.create_bounds`:
   ``inplace`` (https://github.com/NCAS-CMS/cf-python/issues/855)
 * Set new minimum version of `dask`: ``2025.5.1``

cf/data/array/aggregatedarray.py

@@ -19,5 +19,5 @@ def __new__(cls, *args, **kwargs):
         """
         # Override the inherited FragmentFileArray class
         instance = super().__new__(cls)
-        instance._FragmentArray["location"] = FragmentFileArray
+        instance._FragmentArray["uri"] = FragmentFileArray
         return instance

cf/test/create_test_files.py

@@ -2229,11 +2229,11 @@ def _make_ugrid_2(filename):
 
 
 def _make_aggregation_value(filename):
-    """Create an aggregation variable with a 'value' fragment array."""
+    """Create an aggregation variable with 'unique_values'."""
     n = netCDF4.Dataset(filename, "w")
 
     n.Conventions = f"CF-{VN}"
-    n.comment = "A netCDF file with a 'value' aggregation variable."
+    n.comment = "A netCDF file with a 'unique_values' aggregation variable."
 
     n.createDimension("time", 12)
     n.createDimension("level", 1)
@@ -2253,13 +2253,13 @@ def _make_aggregation_value(filename):
     temperature.cell_methods = "time: mean"
     temperature.ancillary_variables = "uid"
     temperature.aggregated_dimensions = "time level latitude longitude"
-    temperature.aggregated_data = "location: fragment_location variable: fragment_variable map: fragment_map"
+    temperature.aggregated_data = "uris: fragment_uris identifiers: fragment_identifiers map: fragment_map"
 
     uid = n.createVariable("uid", str, ())
     uid.long_name = "Fragment dataset unique identifiers"
     uid.aggregated_dimensions = "time"
     uid.aggregated_data = (
-        "unique_value: fragment_value_uid map: fragment_map_uid"
+        "unique_values: fragment_value_uid map: fragment_map_uid"
     )
 
     time = n.createVariable("time", "f4", ("time",))
@@ -2280,16 +2280,16 @@ def _make_aggregation_value(filename):
     longitude.units = "degrees_east"
 
     # Fragment array variables
-    fragment_location = n.createVariable(
-        "fragment_location",
+    fragment_uris = n.createVariable(
+        "fragment_uris",
         str,
         ("a_time", "a_level", "a_latitude", "a_longitude"),
     )
-    fragment_location[0, 0, 0, 0] = "January-March.nc"
-    fragment_location[1, 0, 0, 0] = "April-December.nc"
+    fragment_uris[0, 0, 0, 0] = "January-March.nc"
+    fragment_uris[1, 0, 0, 0] = "April-December.nc"
 
-    fragment_variable = n.createVariable("fragment_variable", str, ())
-    fragment_variable[...] = "temperature"
+    fragment_identifiers = n.createVariable("fragment_identifiers", str, ())
+    fragment_identifiers[...] = "temperature"
 
     fragment_map = n.createVariable(
         "fragment_map", "i4", ("a_map_j4", "a_map_i2")

cf/test/test_CFA.py

@@ -130,8 +130,8 @@ def test_CFA_uri_0(self):
             )
 
             nc = netCDF4.Dataset(cfa_file, "r")
-            cfa_location = nc.variables["cfa_location"]
-            self.assertEqual(cfa_location[...], filename)
+            fragment_uris = nc.variables["fragment_uris"]
+            self.assertEqual(fragment_uris[...], filename)
             nc.close()
 
             g = cf.read(cfa_file)
@@ -168,8 +168,8 @@ def test_CFA_uri_1(self):
             )
 
             nc = netCDF4.Dataset(cfa_file2, "r")
-            cfa_location = nc.variables["cfa_location"]
-            self.assertEqual(cfa_location[...], filename)
+            fragment_uris = nc.variables["fragment_uris"]
+            self.assertEqual(fragment_uris[...], filename)
             nc.close()
 
     def test_CFA_constructs(self):
@@ -271,8 +271,8 @@ def test_CFA_scalar(self):
         h = cf.read(cfa_file)[0]
         self.assertTrue(h.equals(f))
 
-    def test_CFA_value(self):
-        """Test the value fragment array variable."""
+    def test_CFA_unique_value(self):
+        """Test the unique value fragment array variable."""
         write = True
         for aggregation_value_file in (self.aggregation_value, cfa_file):
             f = cf.read(aggregation_value_file, cfa_write="all")
@@ -288,7 +288,7 @@ def test_CFA_value(self):
                 fa.data.nc_get_aggregated_data(),
                 {
                     "map": "fragment_map_uid",
-                    "unique_value": "fragment_value_uid",
+                    "unique_values": "fragment_value_uid",
                 },
             )