fast_lyapunov_max

gala.dynamics.nonlinear.fast_lyapunov_max(w0, potential, dt, n_steps, d0=1e-05, n_steps_per_pullback=10, noffset_orbits=2, t1=0.0, atol=1e-10, rtol=1e-10, nmax=0, return_orbit=True)[source]

Compute the maximum Lyapunov exponent using a C-implemented estimator that uses the DOPRI853 integrator.

Parameters:

w0 : PhaseSpacePosition, array_like

Initial conditions.

dt : numeric

Timestep.

n_steps : int

Number of steps to run for.

d0 : numeric (optional)

The initial separation.

n_steps_per_pullback : int (optional)

Number of steps to run before re-normalizing the offset vectors.

noffset_orbits : int (optional)

Number of offset orbits to run.

t1 : numeric (optional)

Time of initial conditions. Assumed to be t=0.

return_orbit : bool (optional)

Store the full orbit for the parent and all offset orbits.

Returns:

LEs : Quantity

Lyapunov exponents calculated from each offset / deviation orbit.

orbit : CartesianOrbit (optional)