def METHOD_NAME():
    # Example taken from:
    # Snyder, J.P. Map Projections A Working Manual, 1987, page 338.
    R = 3.0
    lat_0 = 40.0  # 40 degrees North latitude
    lon_0 = -100.0  # 100 degrees West longitude
    lat = -20.0  # 20 degrees S latitude
    lon = 100.0  # 100.0 E longitude
    x = -5.8311398
    y = 5.5444634
    with warnings.catch_warnings():  # invalid divide is handled by code
        warnings.simplefilter("ignore", category=RuntimeWarning)
        projparams = {"proj": "pyart_aeqd", "lon_0": lon_0, "lat_0": lat_0, "R": R}
        x, y = transforms.geographic_to_cartesian(lon, lat, projparams)
    assert_almost_equal(x, -5.8311398, 7)
    assert_almost_equal(y, 5.5444634, 7)
    # Use the default R value
    with warnings.catch_warnings():  # invalid divide is handled by code
        warnings.simplefilter("ignore", category=RuntimeWarning)
        projparams = {"proj": "pyart_aeqd", "lon_0": lon_0, "lat_0": lat_0}
        x, y = transforms.geographic_to_cartesian(lon, lat, projparams)
    x /= 6370997.0 / 3.0
    y /= 6370997.0 / 3.0
    assert_almost_equal(x, -5.8311398, 7)
    assert_almost_equal(y, 5.5444634, 7)