Merge pull request #458 from bjodah/DenseMatrixBase-abs

add DenseMatrixBase.__abs__

Author: bjodah

symengine/lib/symengine_wrapper.in.pyx

@@ -3529,6 +3529,9 @@ cdef class DenseMatrixBase(MatrixBase):
     def __neg__(self):
         return self.mul_scalar(-1)
 
+    def __abs__(self):
+        return self.applyfunc(abs)
+
     def __getitem__(self, item):
         if isinstance(item, slice):
             if (self.ncols() == 0 or self.nrows() == 0):

symengine/tests/test_matrices.py

@@ -286,11 +286,13 @@ def test_mul_scalar():
     assert a * A == DenseMatrix(2, 2, [a, 2*a, 3*a, 4*a])
 
 
-def test_neg():
+def test_neg_abs():
     A = DenseMatrix(2, 3, [1, 2, 3, 4, 5, 6])
     B = DenseMatrix(2, 3, [-1, -2, -3, -4, -5, -6])
     assert -A == B
 
+    assert A == abs(B)
+
 
 def test_sub():
     A = DenseMatrix(2, 2, [1, 2, 3, 4])