diff --git a/symengine/lib/symengine_wrapper.pyx b/symengine/lib/symengine_wrapper.pyx
index 4c5f0f82..b38eb080 100644
--- a/symengine/lib/symengine_wrapper.pyx
+++ b/symengine/lib/symengine_wrapper.pyx
@@ -3895,7 +3895,7 @@ cdef class DenseMatrixBase(MatrixBase):
                 l.append(c2py(A.get(i, j))._sympy_())
             s.append(l)
         import sympy
-        return sympy.Matrix(s)
+        return sympy.ImmutableMatrix(s)
 
     def _sage_(self):
         s = []
@@ -3906,7 +3906,7 @@ cdef class DenseMatrixBase(MatrixBase):
                 l.append(c2py(A.get(i, j))._sage_())
             s.append(l)
         import sage.all as sage
-        return sage.Matrix(s)
+        return sage.Matrix(s, immutable=True)
 
     def dump_real(self, double[::1] out):
         cdef size_t ri, ci, nr, nc
@@ -4046,6 +4046,12 @@ cdef class ImmutableDenseMatrix(DenseMatrixBase):
     def __setitem__(self, key, value):
         raise TypeError("Cannot set values of {}".format(self.__class__))
 
+    def _applyfunc(self, f):
+        res = DenseMatrix(self)
+        res._applyfunc(f)
+        return ImmutableDenseMatrix(res)
+
+
 ImmutableMatrix = ImmutableDenseMatrix
 
 
diff --git a/symengine/tests/test_matrices.py b/symengine/tests/test_matrices.py
index 55ebd046..de997529 100644
--- a/symengine/tests/test_matrices.py
+++ b/symengine/tests/test_matrices.py
@@ -3,13 +3,23 @@
     Rational, function_symbol, I, NonSquareMatrixError, ShapeError, zeros,
     ones, eye, ImmutableMatrix)
 from symengine.test_utilities import raises
+import unittest
 
 
 try:
     import numpy as np
-    HAVE_NUMPY = True
+    have_numpy = True
 except ImportError:
-    HAVE_NUMPY = False
+    have_numpy = False
+    
+try:
+    import sympy
+    from sympy.core.cache import clear_cache
+    import atexit
+    atexit.register(clear_cache)
+    have_sympy = True
+except ImportError:
+    have_sympy = False
 
 
 def test_init():
@@ -520,10 +530,8 @@ def test_reshape():
     assert C != A
 
 
-# @pytest.mark.skipif(not HAVE_NUMPY, reason='requires numpy')
+@unittest.skipIf(not have_numpy, 'requires numpy')
 def test_dump_real():
-    if not HAVE_NUMPY:  # nosetests work-around
-        return
     ref = [1, 2, 3, 4]
     A = DenseMatrix(2, 2, ref)
     out = np.empty(4)
@@ -531,10 +539,9 @@ def test_dump_real():
     assert np.allclose(out, ref)
 
 
-# @pytest.mark.skipif(not HAVE_NUMPY, reason='requires numpy')
+
+@unittest.skipIf(not have_numpy, 'requires numpy')
 def test_dump_complex():
-    if not HAVE_NUMPY:  # nosetests work-around
-        return
     ref = [1j, 2j, 3j, 4j]
     A = DenseMatrix(2, 2, ref)
     out = np.empty(4, dtype=np.complex128)
@@ -741,3 +748,8 @@ def test_repr_latex():
     latex_string = testmat._repr_latex_()
     assert isinstance(latex_string, str)
     init_printing(False)
+
+@unittest.skipIf(not have_sympy, "SymPy not installed")
+def test_simplify():
+    A = ImmutableMatrix([1])
+    assert type(A.simplify()) == type(A)