Fix casting bug

Author: zaxtax

pymc/aesaraf.py

@@ -47,6 +47,7 @@
 from aesara.graph.fg import FunctionGraph
 from aesara.graph.op import Op, compute_test_value
 from aesara.sandbox.rng_mrg import MRG_RandomStream as RandomStream
+from aesara.scalar.basic import Cast
 from aesara.tensor.elemwise import Elemwise
 from aesara.tensor.random.op import RandomVariable
 from aesara.tensor.shape import SpecifyShape
@@ -232,6 +233,9 @@ def extract_obs_data(x: TensorVariable) -> np.ndarray:
         return x.data
     if isinstance(x, SharedVariable):
         return x.get_value()
+    if x.owner and isinstance(x.owner.op, Elemwise) and isinstance(x.owner.op.scalar_op, Cast):
+        array_data = extract_obs_data(x.owner.inputs[0])
+        return array_data.astype(x.type.dtype)
     if x.owner and isinstance(x.owner.op, (AdvancedIncSubtensor, AdvancedIncSubtensor1)):
         array_data = extract_obs_data(x.owner.inputs[0])
         mask_idx = tuple(extract_obs_data(i) for i in x.owner.inputs[2:])

pymc/tests/test_aesaraf.py

@@ -380,6 +380,14 @@ def test_extract_obs_data():
     assert isinstance(res, np.ndarray)
     assert np.ma.allequal(res, data_m)
 
+    # Cast check
+    data = np.array(5)
+    t = at.cast(at.as_tensor(5.0), np.int64)
+    res = extract_obs_data(t)
+
+    assert isinstance(res, np.ndarray)
+    assert np.array_equal(res, data)
+
 
 @pytest.mark.parametrize("input_dtype", ["int32", "int64", "float32", "float64"])
 def test_pandas_to_array(input_dtype):

pymc/tests/test_sampling.py

@@ -1078,15 +1078,15 @@ def test_shared(self):
             o = pm.Deterministic("o", obs)
             gen1 = pm.sample_prior_predictive(draws)
 
-        assert gen1.prior["y"].shape == (1, draws, n1)
+        assert gen1.prior_predictive["y"].shape == (1, draws, n1)
         assert gen1.prior["o"].shape == (1, draws, n1)
 
         n2 = 20
         obs.set_value(np.random.rand(n2) < 0.5)
         with m:
             gen2 = pm.sample_prior_predictive(draws)
 
-        assert gen2.prior["y"].shape == (1, draws, n2)
+        assert gen2.prior_predictive["y"].shape == (1, draws, n2)
         assert gen2.prior["o"].shape == (1, draws, n2)
 
     def test_density_dist(self):