test_matrices.py 文件源码

def test_pinv():
    from sympy.abc import a, b, c, d, e, f
    # Pseudoinverse of an invertible matrix is the inverse.
    A1 = Matrix([[a, b], [c, d]])
    assert simplify(A1.pinv()) == simplify(A1.inv())
    # Test the four properties of the pseudoinverse for various matrices.
    As = [Matrix([[13, 104], [2212, 3], [-3, 5]]),
          Matrix([[1, 7, 9], [11, 17, 19]]),
          Matrix([a, b])]
    for A in As:
        A_pinv = A.pinv()
        AAp = A * A_pinv
        ApA = A_pinv * A
        assert simplify(AAp * A) == A
        assert simplify(ApA * A_pinv) == A_pinv
        assert AAp.H == AAp
        assert ApA.H == ApA