Add string arguments for Cube methods

docs/iris/src/whatsnew/latest.rst

@@ -22,7 +22,8 @@ This document explains the changes made to Iris for this release
 🐛 Bugs Fixed
 =============
 
-* N/A
+* `@gcaria`_ fixed :meth:`~iris.cube.Cube.cell_measure_dims` to also accept the string name of a :class:`~iris.coords.CellMeasure`. (:pull:`3931`)
+* `@gcaria`_ fixed :meth:`~iris.cube.Cube.ancillary_variable_dims` to also accept the string name of a :class:`~iris.coords.AncillaryVariable`. (:pull:`3931`)
 
 
 💣 Incompatible Changes
@@ -53,3 +54,5 @@ This document explains the changes made to Iris for this release
 ===========
 
 * N/A
+
+.. _@gcaria: https://github.com/gcaria

lib/iris/cube.py

@@ -1400,10 +1400,12 @@ def cell_measure_dims(self, cell_measure):
         Returns a tuple of the data dimensions relevant to the given
         CellMeasure.
 
-        * cell_measure
-            The CellMeasure to look for.
+        * cell_measure (string or CellMeasure)
+            The (name of the) cell measure to look for.
 
         """
+        cell_measure = self.cell_measure(cell_measure)
+
         # Search for existing cell measure (object) on the cube, faster lookup
         # than equality - makes no functional difference.
         matches = [
@@ -1422,10 +1424,12 @@ def ancillary_variable_dims(self, ancillary_variable):
         Returns a tuple of the data dimensions relevant to the given
         AncillaryVariable.
 
-        * ancillary_variable
-            The AncillaryVariable to look for.
+        * ancillary_variable (string or AncillaryVariable)
+            The (name of the) AncillaryVariable to look for.
 
         """
+        ancillary_variable = self.ancillary_variable(ancillary_variable)
+
         # Search for existing ancillary variable (object) on the cube, faster
         # lookup than equality - makes no functional difference.
         matches = [

lib/iris/tests/unit/cube/test_Cube.py

@@ -2044,6 +2044,14 @@ def test_remove_ancilliary_variable(self):
         )
         self.assertEqual(self.cube._ancillary_variables_and_dims, [])
 
+    def test_remove_ancilliary_variable_by_name(self):
+        self.cube.remove_ancillary_variable("Quality of Detection")
+        self.assertEqual(self.cube._ancillary_variables_and_dims, [])
+
+    def test_fail_remove_ancilliary_variable_by_name(self):
+        with self.assertRaises(AncillaryVariableNotFoundError):
+            self.cube.remove_ancillary_variable("notname")
+
 
 class Test__getitem_CellMeasure(tests.IrisTest):
     def setUp(self):
@@ -2146,6 +2154,16 @@ def test_fail_ancill_variable_dims(self):
         with self.assertRaises(AncillaryVariableNotFoundError):
             self.cube.ancillary_variable_dims(ancillary_variable)
 
+    def test_ancillary_variable_dims_by_name(self):
+        ancill_var_dims = self.cube.ancillary_variable_dims(
+            "number_of_observations"
+        )
+        self.assertEqual(ancill_var_dims, (0, 1))
+
+    def test_fail_ancillary_variable_dims_by_name(self):
+        with self.assertRaises(AncillaryVariableNotFoundError):
+            self.cube.ancillary_variable_dims("notname")
+
 
 class TestCellMeasures(tests.IrisTest):
     def setUp(self):
@@ -2194,6 +2212,14 @@ def test_fail_cell_measure_dims(self):
         with self.assertRaises(CellMeasureNotFoundError):
             _ = self.cube.cell_measure_dims(a_cell_measure)
 
+    def test_cell_measure_dims_by_name(self):
+        cm_dims = self.cube.cell_measure_dims("area")
+        self.assertEqual(cm_dims, (0, 1))
+
+    def test_fail_cell_measure_dims_by_name(self):
+        with self.assertRaises(CellMeasureNotFoundError):
+            self.cube.cell_measure_dims("notname")
+
 
 class Test_transpose(tests.IrisTest):
     def setUp(self):