diff --git a/imperative/python/test/helpers/utils.py b/imperative/python/test/helpers/utils.py
index 10cd4a8b5168f59834b244c8e2c0fa5e6eda5575..99ce51b2614cef6b4cecf8083b7f2821e1b858e3 100644
--- a/imperative/python/test/helpers/utils.py
+++ b/imperative/python/test/helpers/utils.py
@@ -94,45 +94,49 @@ def opr_test(
 
         return inp, outp
 
-    if len(cases) == 0:
-        raise ValueError("should give one case at least")
+    def run_index(index):
+        inp, outp = get_param(cases, index)
+        inp_tensor = [make_tensor(inpi, network) for inpi in inp]
 
-    if not callable(func):
-        raise ValueError("the input func should be callable")
+        if test_trace and not network:
+            copied_inp = inp_tensor.copy()
+            for symbolic in [False, True]:
+                traced_func = trace(symbolic=symbolic)(func)
 
-    inp, outp = get_param(cases, 0)
-    inp_tensor = [make_tensor(inpi, network) for inpi in inp]
+                for _ in range(3):
+                    traced_results = traced_func(*copied_inp, **kwargs)
+                check_results(traced_results, outp)
 
-    if test_trace and not network:
-        copied_inp = inp_tensor.copy()
-        for symbolic in [False, True]:
-            traced_func = trace(symbolic=symbolic)(func)
+            dumped_func = trace(symbolic=True, capture_as_const=True)(func)
+            dumped_results = dumped_func(*copied_inp, **kwargs)
+            check_results(dumped_results, outp)
 
-            for _ in range(3):
-                traced_results = traced_func(*copied_inp, **kwargs)
-            check_results(traced_results, outp)
+            file = io.BytesIO()
+            dump_info = dumped_func.dump(file)
+            file.seek(0)
 
-        dumped_func = trace(symbolic=True, capture_as_const=True)(func)
-        dumped_results = dumped_func(*copied_inp, **kwargs)
-        check_results(dumped_results, outp)
+            # arg_name has pattern arg_xxx, xxx is int value
+            def take_number(arg_name):
+                return int(arg_name.split("_")[-1])
 
-        file = io.BytesIO()
-        dump_info = dumped_func.dump(file)
-        file.seek(0)
+            input_names = dump_info[4]
+            inps_np = [i.numpy() for i in copied_inp]
+            input_names.sort(key=take_number)
+            inp_dict = dict(zip(input_names, inps_np))
+            infer_cg = cgtools.GraphInference(file)
 
-        # arg_name has pattern arg_xxx, xxx is int value
-        def take_number(arg_name):
-            return int(arg_name.split("_")[-1])
+            # assume #outputs == 1
+            loaded_results = list(infer_cg.run(inp_dict=inp_dict).values())[0]
+            check_results(loaded_results, outp)
 
-        input_names = dump_info[4]
-        inps_np = [i.numpy() for i in copied_inp]
-        input_names.sort(key=take_number)
-        inp_dict = dict(zip(input_names, inps_np))
-        infer_cg = cgtools.GraphInference(file)
+        results = func(*inp_tensor, **kwargs)
+        check_results(results, outp)
 
-        # assume #outputs == 1
-        loaded_results = list(infer_cg.run(inp_dict=inp_dict).values())[0]
-        check_results(loaded_results, outp)
+    if len(cases) == 0:
+        raise ValueError("should give one case at least")
+
+    if not callable(func):
+        raise ValueError("the input func should be callable")
 
-    results = func(*inp_tensor, **kwargs)
-    check_results(results, outp)
+    for index in range(len(cases)):
+        run_index(index)
diff --git a/imperative/python/test/unit/functional/test_functional.py b/imperative/python/test/unit/functional/test_functional.py
index a4366a6c405ca85b8efb13f98162a0fb6e7cb076..612f6612fca4a76912643630ca9cf8e9179e261f 100644
--- a/imperative/python/test/unit/functional/test_functional.py
+++ b/imperative/python/test/unit/functional/test_functional.py
@@ -79,7 +79,7 @@ def test_matinv():
     opr_test(
         cases,
         F.matinv,
-        compare_fn=lambda x, y: np.testing.assert_allclose(x.numpy(), y, rtol=1e-5),
+        compare_fn=lambda x, y: np.testing.assert_allclose(x.numpy(), y, rtol=1e-4),
         ref_fn=np.linalg.inv,
     )