Updates units from "metres" to "m".

improver/utilities/spatial.py

@@ -133,7 +133,7 @@ def distance_to_number_of_grid_cells(
     if distance <= 0:
         raise ValueError(f"Please specify a positive distance in metres. {d_error}")
     # calculate grid spacing along chosen axis
-    grid_spacing_metres = calculate_grid_spacing(cube, "metres", axis=axis)
+    grid_spacing_metres = calculate_grid_spacing(cube, "m", axis=axis)
     grid_cells = distance / abs(grid_spacing_metres)
 
     if return_int:
@@ -193,7 +193,7 @@ def build_distances_cube(distances: ndarray, dims: List[Coord], axis: str) -> Cu
         return Cube(
             distances,
             long_name=f"{axis}_distance_between_grid_points",
-            units="metres",
+            units="m",
             dim_coords_and_dims=dims,
         )
 
@@ -343,7 +343,7 @@ def _get_x_distances(self) -> Cube:
             A cube containing the x-axis distances between the grid points of the input
             cube in metres.
         """
-        x_distances = calculate_grid_spacing(self.cube, axis="x", units="metres")
+        x_distances = calculate_grid_spacing(self.cube, axis="x", units="m")
         data = np.full(
             (self.cube.shape[0], len(self.x_separations_axis.points)), x_distances
         )
@@ -362,7 +362,7 @@ def _get_y_distances(self) -> Cube:
             A cube containing the vertical distances between the grid points of the input
             cube in metres.
         """
-        y_grid_spacing = calculate_grid_spacing(self.cube, axis="y", units="metres")
+        y_grid_spacing = calculate_grid_spacing(self.cube, axis="y", units="m")
         data = np.full(
             (len(self.y_separation_axis.points), self.cube.data.shape[1]),
             y_grid_spacing,
@@ -434,8 +434,8 @@ def _cube_xy_dimensions_are_distances(cube: Cube) -> bool:
             Boolean representing whether the cube has x and y axes defined in a distance unit.
         """
         try:
-            cube.coord(axis="x").convert_units("metres")
-            cube.coord(axis="y").convert_units("metres")
+            cube.coord(axis="x").convert_units("m")
+            cube.coord(axis="y").convert_units("m")
             return True
         except (
             TypeError,

improver_tests/utilities/test_DistanceBetweenGridPoints.py

@@ -207,7 +207,7 @@ def test_equalarea_cube(test_case):
         (calculated_x_distances_cube, calculated_y_distances_cube),
         (expected_x_distances, expected_y_distances),
     ):
-        assert result.units == "metres"
+        assert result.units == "m"
         np.testing.assert_allclose(result.data, expected.data, rtol=2e-5, atol=0)
 
 
@@ -227,7 +227,7 @@ def test_equalarea_cube_nonstandard_units():
         (calculated_x_distances_cube, calculated_y_distances_cube),
         (expected_x_distances, expected_y_distances),
     ):
-        assert result.units == "metres"
+        assert result.units == "m"
         np.testing.assert_allclose(result.data, expected.data, rtol=2e-5, atol=0)
 
 
@@ -250,7 +250,7 @@ def test_transverse_mercator_cube():
         (calculated_x_distances_cube, calculated_y_distances_cube),
         (expected_x_distances, expected_y_distances),
     ):
-        assert result.units == "metres"
+        assert result.units == "m"
         np.testing.assert_allclose(
             result.data, expected.data, rtol=2e-3, atol=0
         )  # Allowing 0.2% error for spherical earth approximation.
@@ -280,7 +280,7 @@ def test_distance_cube_with_no_coordinate_system():
         (calculated_x_distances_cube, calculated_y_distances_cube),
         (expected_x_distances, expected_y_distances),
     ):
-        assert result.units == "metres"
+        assert result.units == "m"
         np.testing.assert_allclose(result.data, expected.data, rtol=2e-5, atol=0)