strengthen tensor train circuit template unite test

tests/templates/test_tensor_factorizations.py

@@ -1,5 +1,6 @@
 import itertools
 
+import numpy as np
 import pytest
 
 from cirkit.symbolic.dtypes import DataType
@@ -137,6 +138,19 @@ def test_factorization_tensor_train(rank: int, factor_param: Parameterization |
     assert all(isinstance(sl, HadamardLayer) for sl in product_layers)
     assert len(product_layers) == (len(shape) - 2) * rank + 1
     assert len(sum_layers) == len(shape) - 1
+    for sl in sum_layers:
+        assert len(sl.weight.nodes) == 1
+        weight = sl.weight.nodes[0]
+        assert isinstance(weight, ConstantParameter)
+        value = np.reshape(weight.value, shape=(sl.num_output_units, sl.arity, sl.num_input_units))
+        ones = np.ones(sl.num_input_units)
+        zeros = np.zeros(sl.num_input_units)
+        for i in range(sl.num_output_units):
+            assert np.all(value[i, i] == ones)
+            for j in range(sl.num_output_units):
+                if i == j:
+                    continue
+                assert np.all(value[i, j] == zeros)
     if factor_param is not None:
         for sl in input_layers:
             assert len(sl.weight.nodes) == 1