Python Orbit.from_classical方法代码示例

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_bad_hyperbolic_raises_exception():
    bad_a = 1.0 * u.AU
    ecc = 1.5 * u.one
    _inc = 100 * u.deg  # Unused inclination
    _a = 1.0 * u.deg  # Unused angle
    _body = Sun  # Unused body
    with pytest.raises(ValueError) as excinfo:
        Orbit.from_classical(_body, bad_a, ecc, _inc, _a, _a, _a)
    assert "Hyperbolic orbits have negative semimajor axis" in excinfo.exconly()

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_parabolic_elements_fail_early():
    attractor = Earth
    ecc = 1.0 * u.one
    _d = 1.0 * u.AU  # Unused distance
    _a = 1.0 * u.deg  # Unused angle
    with pytest.raises(ValueError) as excinfo:
        Orbit.from_classical(attractor, _d, ecc, _a, _a, _a, _a)
    assert (
        "ValueError: For parabolic orbits use Orbit.parabolic instead"
        in excinfo.exconly()
    )

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_state_raises_unitserror_if_elements_units_are_wrong():
    _d = 1.0 * u.AU  # Unused distance
    _ = 0.5 * u.one  # Unused dimensionless value
    _a = 1.0 * u.deg  # Unused angle
    wrong_angle = 1.0 * u.AU
    with pytest.raises(u.UnitsError) as excinfo:
        Orbit.from_classical(Sun, _d, _, _a, _a, _a, wrong_angle)
    assert (
        "UnitsError: Argument 'nu' to function 'from_classical' must be in units convertible to 'rad'."
        in excinfo.exconly()
    )

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_bad_inclination_raises_exception():
    _d = 1.0 * u.AU  # Unused distance
    _ = 0.5 * u.one  # Unused dimensionless value
    _a = 1.0 * u.deg  # Unused angle
    _body = Sun  # Unused body
    bad_inc = 200 * u.deg
    with pytest.raises(ValueError) as excinfo:
        Orbit.from_classical(_body, _d, _, bad_inc, _a, _a, _a)
    assert (
        "ValueError: Inclination must be between 0 and 180 degrees" in excinfo.exconly()
    )

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def orbit_from_record(record):
    """Return :py:class:`~poliastro.twobody.orbit.Orbit` given a record.

        Retrieve info from JPL DASTCOM5 database.

        Parameters
        ----------
        record : int
            Object record.

        Returns
        -------
        orbit : ~poliastro.twobody.orbit.Orbit
            NEO orbit.

        """
    body_data = read_record(record)
    a = body_data['A'].item() * u.au
    ecc = body_data['EC'].item() * u.one
    inc = body_data['IN'].item() * u.deg
    raan = body_data['OM'].item() * u.deg
    argp = body_data['W'].item() * u.deg
    m = body_data['MA'].item() * u.deg
    nu = M_to_nu(m, ecc)
    epoch = Time(body_data['EPOCH'].item(), format='jd', scale='tdb')

    orbit = Orbit.from_classical(Sun, a, ecc, inc, raan, argp, nu, epoch)
    orbit._frame = HeliocentricEclipticJ2000(obstime=epoch)
    return orbit

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_perifocal_points_to_perigee():
    _d = 1.0 * u.AU  # Unused distance
    _ = 0.5 * u.one  # Unused dimensionless value
    _a = 1.0 * u.deg  # Unused angle
    ss = Orbit.from_classical(Sun, _d, _, _a, _a, _a, _a)
    p, _, _ = ss.pqw()
    assert_allclose(p, ss.e_vec / ss.ecc)

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_default_time_for_new_state():
    _d = 1.0 * u.AU  # Unused distance
    _ = 0.5 * u.one  # Unused dimensionless value
    _a = 1.0 * u.deg  # Unused angle
    _body = Sun  # Unused body
    expected_epoch = J2000
    ss = Orbit.from_classical(_body, _d, _, _a, _a, _a, _a)
    assert ss.epoch == expected_epoch

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_sample_numpoints():
    _d = 1.0 * u.AU  # Unused distance
    _ = 0.5 * u.one  # Unused dimensionless value
    _a = 1.0 * u.deg  # Unused angle
    _body = Sun  # Unused body
    ss = Orbit.from_classical(_body, _d, _, _a, _a, _a, _a)
    positions = ss.sample(values=50)
    assert len(positions) == 50

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_perigee_and_apogee():
    expected_r_a = 500 * u.km
    expected_r_p = 300 * u.km
    a = (expected_r_a + expected_r_p) / 2
    ecc = expected_r_a / a - 1
    _a = 1.0 * u.deg  # Unused angle
    ss = Orbit.from_classical(Earth, a, ecc, _a, _a, _a, _a)
    assert_allclose(ss.r_a.to(u.km).value, expected_r_a.to(u.km).value)
    assert_allclose(ss.r_p.to(u.km).value, expected_r_p.to(u.km).value)

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_apply_maneuver_changes_epoch():
    _d = 1.0 * u.AU  # Unused distance
    _ = 0.5 * u.one  # Unused dimensionless value
    _a = 1.0 * u.deg  # Unused angle
    ss = Orbit.from_classical(Sun, _d, _, _a, _a, _a, _a)
    dt = 1 * u.h
    dv = [0, 0, 0] * u.km / u.s
    orbit_new = ss.apply_maneuver([(dt, dv)])
    assert orbit_new.epoch == ss.epoch + dt

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_convert_from_rv_to_coe():
    # Data from Vallado, example 2.6
    attractor = Earth
    p = 11067.790 * u.km
    ecc = 0.83285 * u.one
    inc = 87.87 * u.deg
    raan = 227.89 * u.deg
    argp = 53.38 * u.deg
    nu = 92.335 * u.deg
    expected_r = [6525.344, 6861.535, 6449.125] * u.km
    expected_v = [4.902276, 5.533124, -1.975709] * u.km / u.s

    r, v = Orbit.from_classical(
        attractor, p / (1 - ecc ** 2), ecc, inc, raan, argp, nu
    ).rv()

    assert_quantity_allclose(r, expected_r, rtol=1e-5)
    assert_quantity_allclose(v, expected_v, rtol=1e-5)

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def test_orbits_are_same():
    epoch = Time("2018-07-23")
    # Orbit Parameters of Ceres
    # Taken from https://ssd.jpl.nasa.gov/horizons.cgi
    ss = Orbit.from_classical(
        Sun,
        2.767107584017257 * u.au,
        0.07554802949294502 * u.one,
        27.18502520750381 * u.deg,
        23.36913256044832 * u.deg,
        132.2919806192451 * u.deg,
        21.28958091587153 * u.deg,
        epoch,
    )
    ss1 = Orbit.from_horizons(name="Ceres", epoch=epoch)
    assert ss.pqw()[0].value.all() == ss1.pqw()[0].value.all()
    assert ss.r_a == ss1.r_a
    assert ss.a == ss1.a

# 需要导入模块: from poliastro.twobody.orbit import Orbit [as 别名]
# 或者: from poliastro.twobody.orbit.Orbit import from_classical [as 别名]
def orbit_from_spk_id(spk_id, api_key=None):
    """Return :py:class:`~poliastro.twobody.orbit.Orbit` given a SPK-ID.

    Retrieve info from NASA NeoWS API, and therefore
    it only works with NEAs (Near Earth Asteroids).

    Parameters
    ----------
    spk_id : str
        SPK-ID number, which is given to each body by JPL.
    api_key : str
        NASA OPEN APIs key (default: `DEMO_KEY`)

    Returns
    -------
    orbit : ~poliastro.twobody.orbit.Orbit
        NEA orbit.

    """
    payload = {'api_key': api_key or DEFAULT_API_KEY}

    response = requests.get(NEOWS_URL + spk_id, params=payload)
    response.raise_for_status()

    orbital_data = response.json()['orbital_data']

    attractor = Sun
    a = float(orbital_data['semi_major_axis']) * u.AU
    ecc = float(orbital_data['eccentricity']) * u.one
    inc = float(orbital_data['inclination']) * u.deg
    raan = float(orbital_data['ascending_node_longitude']) * u.deg
    argp = float(orbital_data['perihelion_argument']) * u.deg
    m = float(orbital_data['mean_anomaly']) * u.deg
    nu = M_to_nu(m.to(u.rad), ecc)
    epoch = Time(float(orbital_data['epoch_osculation']), format='jd', scale='tdb')

    ss = Orbit.from_classical(attractor, a, ecc, inc,
                              raan, argp, nu, epoch, plane=Planes.EARTH_ECLIPTIC)
    return ss