def install(h, pip, groups, save, save_dev, packages):
    """Install a pip or bower package."""
    if groups:
        groups = [text_type.strip(group) for group in groups.split(",")]
    else:
        groups = h.requirements.keys()

    if not packages:
        for group in groups:
            if group not in h.requirements:
                warning("{} not in requirements".format(group))
                continue
            install = (h.install_bower if group.startswith("bower")
                       else h.install_pip)
            for requirement in h.requirements[group]:
                install(str(requirement), save=False, save_dev=False)
    if pip:
        for package in packages:
            h.install_pip(package, save=save, save_dev=save_dev)
    else:
        for package in packages:
            h.install_bower(package, save=save, save_dev=save_dev)
def test_fresnel_coefficients():
    assert all(ae(i, j, 5) for i, j in zip(
        fresnel_coefficients(0.5, 1, 1.33),
        [0.11163, -0.17138, 0.83581, 0.82862]))
    assert all(ae(i, j, 5) for i, j in zip(
        fresnel_coefficients(0.5, 1.33, 1),
        [-0.07726, 0.20482, 1.22724, 1.20482]))
    m1 = Medium('m1')
    m2 = Medium('m2', n=2)
    assert all(ae(i, j, 5) for i, j in zip(
        fresnel_coefficients(0.3, m1, m2),
        [0.31784, -0.34865, 0.65892, 0.65135]))
    ans = [[-0.23563, -0.97184], [0.81648, -0.57738]]
    got = fresnel_coefficients(0.6, m2, m1)
    for i, j in zip(got, ans):
        for a, b in zip(i.as_real_imag(), j):
            assert ae(a, b, 5)