def get_eccentric_anomaly_old(M, e):
"""
Get the eccentric anomaly (E) from the mean anomaly (M) and orbital eccentricity (e)
Uses the equation M = E - esinE
"""
if HelperFunctions.IsListlike(M):
return [get_eccentric_anomaly(Mi, e) for Mi in M]
chisquare = lambda E: (E - e * np.sin(E) - M)**2
output = minimize_scalar(chisquare, bounds=[0, 2 * np.pi], method='brent')
return output.x
def get_eccentric_anomaly(M, e):
"""
Get the eccentric anomaly (E) from the mean anomaly (M) and orbital eccentricity (e)
Uses the equation M = E - esinE
"""
if HelperFunctions.IsListlike(M):
return [get_eccentric_anomaly(Mi, e) for Mi in M]
func = lambda E: E - e * np.sin(E) - M
dfunc = lambda E: 1.0 - e * np.cos(E)
d2func = lambda E: e * np.sin(E)
output = newton(func, np.pi, fprime=dfunc, fprime2=d2func)
#output = minimize_scalar(chisquare, bounds=[0, 2*np.pi], method='brent')
return output
