RF: Drop ndim/shape attributes, make explicit comment on __array_priority__

Author: effigies

nibabel/pointset.py

@@ -66,7 +66,8 @@ class Pointset:
     coordinates: CoordinateArray
     affine: np.ndarray
     homogeneous: bool = False
-    ndim = 2
+
+    # Force use of __rmatmul__ with numpy arrays
     __array_priority__ = 99
 
     def __init__(
@@ -88,11 +89,6 @@ def __init__(
         if np.any(self.affine[-1, :-1] != 0) or self.affine[-1, -1] != 1:
             raise ValueError(f'Invalid affine matrix:\n{self.affine}')
 
-    @property
-    def shape(self) -> tuple[int, int]:
-        """The shape of the coordinate array"""
-        return self.coordinates.shape
-
     @property
     def n_coords(self) -> int:
         """Number of coordinates

nibabel/tests/test_pointset.py

@@ -30,23 +30,15 @@ def test_init(self, shape, homogeneous):
         if homogeneous:
             coords = np.column_stack([coords, np.ones(shape[0])])
 
-        expected_shape = (shape[0], shape[1] + homogeneous)
-
         points = ps.Pointset(coords, homogeneous=homogeneous)
-        assert points.shape == expected_shape
         assert np.allclose(points.affine, np.eye(shape[1] + 1))
         assert points.homogeneous is homogeneous
-        assert points.ndim == 2
-        assert points.n_coords == shape[0]
-        assert points.dim == shape[1]
+        assert (points.n_coords, points.dim) == shape
 
         points = ps.Pointset(coords, affine=np.diag([2] * shape[1] + [1]), homogeneous=homogeneous)
-        assert points.shape == expected_shape
         assert np.allclose(points.affine, np.diag([2] * shape[1] + [1]))
         assert points.homogeneous is homogeneous
-        assert points.ndim == 2
-        assert points.n_coords == shape[0]
-        assert points.dim == shape[1]
+        assert (points.n_coords, points.dim) == shape
 
         # Badly shaped affine
         with pytest.raises(ValueError):
@@ -148,7 +140,8 @@ def test_from_image(self, shape):
         grid = ps.Grid.from_image(img)
         grid_coords = grid.get_coords()
 
-        assert grid.shape == (prod(shape[:3]), 3)
+        assert grid.n_coords == prod(shape[:3])
+        assert grid.dim == 3
         assert np.allclose(grid.affine, affine)
 
         assert np.allclose(grid_coords[0], [0, 0, 0])
@@ -164,7 +157,8 @@ def test_from_mask(self):
         grid = ps.Grid.from_mask(img)
         grid_coords = grid.get_coords()
 
-        assert grid.shape == (1, 3)
+        assert grid.n_coords == 1
+        assert grid.dim == 3
         assert np.array_equal(grid_coords, [[2, 3, 4]])
 
     def test_to_mask(self):