Raise NotImplementedError when trying to convert MaskedArrays

pytensor/scalar/basic.py

@@ -240,6 +240,9 @@ def convert(x, dtype=None):
         The dtype to use for the conversion of `x`.
 
     """
+    if isinstance(x, np.ma.MaskedArray):
+        raise NotImplementedError("MaskedArrays are not supported")
+
     if dtype is not None:
         # in this case, the semantics are that the caller is forcing the dtype
         x_ = _asarray(x, dtype=dtype)

pytensor/tensor/sharedvar.py

@@ -65,6 +65,9 @@ def tensor_constructor(
     optional `shape` argument will override this default.
 
     """
+    if isinstance(value, np.ma.MaskedArray):
+        raise NotImplementedError("MaskedArrays are not supported")
+
     if broadcastable is not None:
         warnings.warn(
             "The `broadcastable` keyword is deprecated; use `shape`.",

tests/tensor/test_basic.py

@@ -537,6 +537,12 @@ def test_constant():
     assert np.array_equal(z.data, x_data)
 
 
+def test_constant_masked_array_not_implemented():
+    x = np.ma.masked_greater(np.array([1, 2, 3, 4]), 3)
+    with pytest.raises(NotImplementedError, match="MaskedArrays are not supported"):
+        constant(x)
+
+
 class TestAsTensorVariable:
     """
     Unit test for ensuring that as_tensor_variable handles Apply objects
@@ -688,6 +694,13 @@ class TestAsTensorVariable:
         with pytest.raises(TypeError):
             at.as_tensor(TestOp(matrix(), matrix()))
 
+    def test_masked_array_not_implemented(
+        self,
+    ):
+        x = np.ma.masked_greater(np.array([1, 2, 3, 4]), 3)
+        with pytest.raises(NotImplementedError, match="MaskedArrays are not supported"):
+            at.as_tensor(x)
+
 
 class TestAlloc:
     dtype = config.floatX

tests/tensor/test_sharedvar.py

@@ -688,3 +688,9 @@ def test_scalar_shared_options():
 def test_get_vector_length():
     x = pytensor.shared(np.array((2, 3, 4, 5)))
     assert get_vector_length(x) == 4
+
+
+def test_shared_masked_array_not_implemented():
+    x = np.ma.masked_greater(np.array([1, 2, 3, 4]), 3)
+    with pytest.raises(NotImplementedError, match="MaskedArrays are not supported"):
+        pytensor.shared(x)