def test_diagonal_inverse_recovers_identity(self): M = Mat([2.0, 0.0], [0.0, 4.0]) Minv = M.inv() assert Minv.__origin__ is M.__origin__ assert type(Minv) is type(M) assert Minv * M == Mat([1.0, 0.0], [0.0, 1.0]) assert M * Minv == Mat([1.0, 0.0], [0.0, 1.0])
def test_inverse_of_diagonal_matrix(self): M = Mat([2, 0], [0, 4]) Minv = M.inv() assert Minv == Mat([0.5, 0], [0, 0.25])