Merge pull request #24993 from Costor/TP_ImmutableMatrix

TensorProduct fails for ImmutableMatrix: correct to MatrixBase instead of Matrix

sympy/physics/quantum/tensorproduct.py

@@ -5,7 +5,8 @@
 from sympy.core.mul import Mul
 from sympy.core.power import Pow
 from sympy.core.sympify import sympify
-from sympy.matrices.dense import MutableDenseMatrix as Matrix
+from sympy.matrices.dense import DenseMatrix as Matrix
+from sympy.matrices.immutable import ImmutableDenseMatrix as ImmutableMatrix
 from sympy.printing.pretty.stringpict import prettyForm
 
 from sympy.physics.quantum.qexpr import QuantumError
@@ -120,7 +121,8 @@ class TensorProduct(Expr):
     is_commutative = False
 
     def __new__(cls, *args):
-        if isinstance(args[0], (Matrix, numpy_ndarray, scipy_sparse_matrix)):
+        if isinstance(args[0], (Matrix, ImmutableMatrix, numpy_ndarray,
+                                                    scipy_sparse_matrix)):
             return matrix_tensor_product(*args)
         c_part, new_args = cls.flatten(sympify(args))
         c_part = Mul(*c_part)

sympy/physics/quantum/tests/test_tensorproduct.py

@@ -1,7 +1,7 @@
 from sympy.core.numbers import I
 from sympy.core.symbol import symbols
 from sympy.core.expr import unchanged
-from sympy.matrices import Matrix, SparseMatrix
+from sympy.matrices import Matrix, SparseMatrix, ImmutableMatrix
 
 from sympy.physics.quantum.commutator import Commutator as Comm
 from sympy.physics.quantum.tensorproduct import TensorProduct
@@ -125,3 +125,13 @@ def test_eval_trace():
                         1.0*A*Dagger(C)*Tr(B*Dagger(D)) +
                         1.0*C*Dagger(A)*Tr(D*Dagger(B)) +
                         1.0*C*Dagger(C)*Tr(D*Dagger(D)))
+
+
+def test_pr24993():
+    from sympy.matrices.expressions.kronecker import matrix_kronecker_product
+    from sympy.physics.quantum.matrixutils    import matrix_tensor_product
+    X = Matrix([[0, 1], [1, 0]])
+    Xi = ImmutableMatrix(X)
+    assert TensorProduct(Xi, Xi) == TensorProduct(X, X)
+    assert TensorProduct(Xi, Xi) == matrix_tensor_product(X, X)
+    assert TensorProduct(Xi, Xi) == matrix_kronecker_product(X, X)