# Buggy code
def from_classical(
    cls,
    attractor,
    a,
    ecc,
    inc,
    raan,
    argp,
    nu,
    epoch=J2000,
    plane=Planes.EARTH_EQUATOR,
):
    """Return `Orbit` from classical orbital elements.

    Parameters
    ----------
    attractor : Body
        Main attractor.
    a : ~astropy.units.Quantity
        Semi-major axis.
    ecc : ~astropy.units.Quantity
        Eccentricity.
    inc : ~astropy.units.Quantity
        Inclination
    raan : ~astropy.units.Quantity
        Right ascension of the ascending node.
    argp : ~astropy.units.Quantity
        Argument of the pericenter.
    nu : ~astropy.units.Quantity
        True anomaly.
    epoch : ~astropy.time.Time, optional
        Epoch, default to J2000.
    plane : ~poliastro.frames.Planes
        Fundamental plane of the frame.

    """
    for element in a, ecc, inc, raan, argp, nu, epoch:
        if not element.isscalar:
            raise ValueError(f"Elements must be scalar, got {element}")

    if ecc == 1.0 * u.one:
        raise ValueError("For parabolic orbits use Orbit.parabolic instead")

    if not 0 * u.deg <= inc <= 180 * u.deg:
        raise ValueError("Inclination must be between 0 and 180 degrees")

    if ecc > 1 and a > 0:
        raise ValueError("Hyperbolic orbits have negative semimajor axis")

    ss = ClassicalState(attractor, a * (1 - ecc**2), ecc, inc, raan, argp, nu, plane)
    return cls(ss, epoch)


# Traceback (FloatingPointError)
$ NUMBA_DISABLE_JIT=1 ipython --no-banner

In [1]: import numpy as np

In [2]: np.seterr(all="raise")
Out[2]: {'divide': 'warn', 'over': 'warn', 'under': 'ignore', 'invalid': 'warn'}

In [3]: import numpy as np
...: import math
...: from astropy import units as u
...: from poliastro.bodies import Earth, Moon
...: from poliastro.twobody import Orbit
...:
...: r=[8.e3, 1.e3, 0.]*u.km
...: v=[-0.5, -0.5, 0.]*u.km/u.s
...: orbit1=Orbit.from_vectors(Earth,r,v)
...: orbit2=orbit1.propagate(1.*u.h)
...:
...:
---------------------------------------------------------------------------
FloatingPointError                        Traceback (most recent call last)
<ipython-input-3-08d7b74965c9> in <module>()
8 v=[-0.5, -0.5, 0.]*u.km/u.s
9 orbit1=Orbit.from_vectors(Earth,r,v)
---> 10 orbit2=orbit1.propagate(1.*u.h)

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/twobody/orbit.py in propagate(self, value, method, rtol, **kwargs)
403                 time_of_flight = time.TimeDelta(value)
404
--> 405             return propagate(self, time_of_flight, method=method, rtol=rtol, **kwargs)
406
407     def sample(self, values=None, method=mean_motion):

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/twobody/propagation.py in propagate(orbit, time_of_flight, method, rtol, **kwargs)
177
178     """
--> 179     r, v = method(orbit, time_of_flight.to(u.s).value, rtol=rtol, **kwargs)
180     return orbit.from_vectors(orbit.attractor, r * u.km, v * u.km / u.s, orbit.epoch + time_of_flight, orbit.plane)

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/twobody/propagation.py in mean_motion(orbit, tofs, **kwargs)
118
119     if not hasattr(tofs, '__len__'):
--> 120         return mean_motion_fast(k, r0, v0, tofs)
121
122     results = [mean_motion_fast(k, r0, v0, tof) for tof in tofs]

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/core/propagation.py in mean_motion(k, r0, v0, tof)
33
34     # get the initial mean anomaly
---> 35     M0 = nu_to_M(nu0, ecc)
36     # strong elliptic or strong hyperbolic orbits
37     if np.abs(ecc - 1.0) > 1e-2:

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/core/angles.py in nu_to_M(nu, ecc, delta)
183     else:
184         D = nu_to_D(nu)
--> 185         M = D_to_M(D, ecc)
186     return M
187

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/core/angles.py in D_to_M(D, ecc)
155 @jit
156 def D_to_M(D, ecc):
--> 157     M = _kepler_equation_parabolic(D, 0.0, ecc)
158     return M
159

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/core/angles.py in _kepler_equation_parabolic(D, M, ecc)
26 @jit
27 def _kepler_equation_parabolic(D, M, ecc):
---> 28     return M_parabolic(ecc, D) - M
29
30

~/.miniconda36/envs/poliastro37/lib/python3.7/site-packages/poliastro/core/angles.py in M_parabolic(ecc, D, tolerance)
41     k = 0
42     while not small_term:
---> 43         term = (ecc - 1.0 / (2.0 * k + 3.0)) * (x ** k)
44         small_term = np.abs(term) < tolerance
45         S += term

FloatingPointError: overflow encountered in double_scalars

# Fixed code
def from_classical(
    cls,
    attractor,
    a,
    ecc,
    inc,
    raan,
    argp,
    nu,
    epoch=J2000,
    plane=Planes.EARTH_EQUATOR,
):
    """Return `Orbit` from classical orbital elements.

    Parameters
    ----------
    attractor : Body
        Main attractor.
    a : ~astropy.units.Quantity
        Semi-major axis.
    ecc : ~astropy.units.Quantity
        Eccentricity.
    inc : ~astropy.units.Quantity
        Inclination
    raan : ~astropy.units.Quantity
        Right ascension of the ascending node.
    argp : ~astropy.units.Quantity
        Argument of the pericenter.
    nu : ~astropy.units.Quantity
        True anomaly.
    epoch : ~astropy.time.Time, optional
        Epoch, default to J2000.
    plane : ~poliastro.frames.Planes
        Fundamental plane of the frame.

    """
    for element in a, ecc, inc, raan, argp, nu, epoch:
        if not element.isscalar:
            raise ValueError(f"Elements must be scalar, got {element}")

    if ecc == 1.0 * u.one:
        raise ValueError("For parabolic orbits use Orbit.parabolic instead")

    if not 0 * u.deg <= inc <= 180 * u.deg:
        raise ValueError("Inclination must be between 0 and 180 degrees")

    if ecc > 1 and a > 0:
        raise ValueError("Hyperbolic orbits have negative semimajor axis")

    if not -np.pi * u.rad <= nu < np.pi * u.rad:
        warn("Wrapping true anomaly to -π <= nu < π", stacklevel=2)
        nu = ((nu + np.pi * u.rad) % (2 * np.pi * u.rad) - np.pi * u.rad).to(nu.unit)

    ss = ClassicalState(attractor, a * (1 - ecc**2), ecc, inc, raan, argp, nu, plane)
    return cls(ss, epoch)