Unidata / MetPy

    y_truth = np.array([3, 2, 1, 0, -1, 0, 2, 2, 0, 1, 0, -1, 0, 2]) * units.degC

    assert_array_almost_equal(x2, x_truth, 6)

    assert_almost_equal(y2, y_truth, 6)

def test_most_unstable_parcel():

    """Tests calculating the most unstable parcel."""

    levels = np.array([1000., 959., 867.9]) * units.mbar

    temperatures = np.array([18.2, 22.2, 17.4]) * units.celsius

    dewpoints = np.array([19., 19., 14.3]) * units.celsius

    ret = most_unstable_parcel(levels, temperatures, dewpoints, depth=100 * units.hPa)

    assert_almost_equal(ret[0], 959.0 * units.hPa, 6)

    assert_almost_equal(ret[1], 22.2 * units.degC, 6)

    assert_almost_equal(ret[2], 19.0 * units.degC, 6)

    cape, cin = cape_cin(p, temperature, dewpoint, parcel_prof)

    assert_almost_equal(cape, 0.08750805 * units('joule / kilogram'), 6)

    assert_almost_equal(cin, -89.8073512 * units('joule / kilogram'), 6)

def test_cape_cin_no_lfc():

    """Tests that CAPE is zero with no LFC."""

    p = np.array([959., 779.2, 751.3, 724.3, 700., 269.]) * units.mbar

    temperature = np.array([22.2, 24.6, 22., 20.4, 18., -10.]) * units.celsius

    dewpoint = np.array([19., -11.2, -10.8, -10.4, -10., -53.2]) * units.celsius

    parcel_prof = parcel_profile(p, temperature[0], dewpoint[0]).to('degC')

    cape, cin = cape_cin(p, temperature, dewpoint, parcel_prof)

    assert_almost_equal(cape, 0.0 * units('joule / kilogram'), 6)

    assert_almost_equal(cin, 0.0 * units('joule / kilogram'), 6)

    """Test LCL calculation convergence failure."""

    with pytest.raises(RuntimeError):

        lcl(1000. * units.mbar, 30. * units.degC, 20. * units.degC, max_iters=2)

def test_lfc_basic():

    """Test LFC calculation."""

    levels = np.array([959., 779.2, 751.3, 724.3, 700., 269.]) * units.mbar

    temperatures = np.array([22.2, 14.6, 12., 9.4, 7., -49.]) * units.celsius

    dewpoints = np.array([19., -11.2, -10.8, -10.4, -10., -53.2]) * units.celsius

    l = lfc(levels, temperatures, dewpoints)

    assert_almost_equal(l[0], 727.468 * units.mbar, 2)

    assert_almost_equal(l[1], 9.705 * units.celsius, 2)