Merge pull request #2263 from Upabjojr/matrix_exp

Allowing exp( ) function to act on a Matrix

sympy/functions/elementary/exponential.py

@@ -279,6 +279,10 @@ def eval(cls, arg):
             if out:
                 return Mul(*out)*cls(Add(*add), evaluate=False)
 
+        elif arg.is_Matrix:
+            from sympy import Matrix
+            return arg.exp()
+
     @property
     def base(self):
         """

sympy/matrices/matrices.py

@@ -3538,10 +3538,11 @@ def row_join(self, rhs):
             raise ShapeError(
                 "`self` and `rhs` must have the same number of rows.")
 
-        newmat = self.zeros(self.rows, self.cols + rhs.cols)
+        from sympy.matrices import MutableMatrix
+        newmat = MutableMatrix.zeros(self.rows, self.cols + rhs.cols)
         newmat[:, :self.cols] = self
         newmat[:, self.cols:] = rhs
-        return newmat
+        return type(self)(newmat)
 
     def col_join(self, bott):
         """Concatenates two matrices along self's last and bott's first row
@@ -3649,12 +3650,13 @@ def col_insert(self, pos, mti):
         if self.rows != mti.rows:
             raise ShapeError("self and mti must have the same number of rows.")
 
-        newmat = self.zeros(self.rows, self.cols + mti.cols)
+        from sympy.matrices import MutableMatrix
+        newmat = MutableMatrix.zeros(self.rows, self.cols + mti.cols)
         i, j = pos, pos + mti.cols
         newmat[:, :i] = self[:, :i]
         newmat[:, i:j] = mti
         newmat[:, j:] = self[:, i:]
-        return newmat
+        return type(self)(newmat)
 
     def replace(self, F, G, map=False):
         """Replaces Function F in Matrix entries with Function G.

sympy/matrices/tests/test_matrices.py

@@ -1450,11 +1450,13 @@ def test_Matrix_berkowitz_charpoly():
 
 def test_exp():
     m = Matrix([[3, 4], [0, -2]])
-    assert m.exp() == \
-        Matrix([[exp(3), -4*exp(-2)/5 + 4*exp(3)/5], [0, exp(-2)]])
+    m_exp = Matrix([[exp(3), -4*exp(-2)/5 + 4*exp(3)/5], [0, exp(-2)]])
+    assert m.exp() == m_exp
+    assert exp(m) == m_exp
 
     m = Matrix([[1, 0], [0, 1]])
     assert m.exp() == Matrix([[E, 0], [0, E]])
+    assert exp(m) == Matrix([[E, 0], [0, E]])
 
 
 def test_has():