def test_invalid_scalar_index(adata, index):
    # https://github.com/theislab/anndata/issues/619
    with pytest.raises(IndexError, match=r".*index.* out of range\."):
        _ = adata[index]
def test_ccode_Rational():
    assert ccode(Rational(3, 7)) == "3.0L/7.0L"
    assert ccode(Rational(18, 9)) == "2"
    assert ccode(Rational(3, -7)) == "-3.0L/7.0L"
    assert ccode(Rational(-3, -7)) == "3.0L/7.0L"
    assert ccode(x + Rational(3, 7)) == "x + 3.0L/7.0L"
    assert ccode(Rational(3, 7)*x) == "(3.0L/7.0L)*x"