forms.py 文件源码

def _keplerian_to_keplerian_mean(cls, coord, center):
        """Conversion from Keplerian to Keplerian Mean

        The difference is the use of Mean anomaly instead of True anomaly
        """

        a, e, i, ?, ?, ? = coord
        if e < 1:
            # Elliptic case
            E = arccos((e + cos(?)) / (1 + e * cos(?)))  # Eccentric anomaly
            M = E - e * sin(E)  # Mean anomaly
        else:
            # Hyperbolic case
            H = arccosh((e + cos(?)) / (1 + e * cos(?)))
            M = e * sinh(H) - H

        return np.array([a, e, i, ?, ?, M], dtype=float)