conatus.expert.ginzburg_landau

conatus.expert.ginzburg_landau(system_at, k_c, parameter, *, kind, observable, h, par=None, **nf_kw)[source]

Ginzburg–Landau coefficients of the instability at wavenumber k_c.

system_at(k) -> (system, x0): the system discretized on the period 2π/k (same parameter values), and its base state. observable: linear functional on the k_c system giving the amplitude of the e^{ik_c x} content (for a cos kx mode: its coefficient, then u = A e^{ikx} + c.c. means observable = 2|A|). h: declared FD step in k.

Parameters:

  • system_at (Callable[[float], tuple[DynamicalSystem, ndarray]])

  • k_c (float)

  • parameter (str)

  • kind (str)

  • observable (Callable[[ndarray], complex])

  • h (float)

  • par (Mapping[str, float] | None)

Return type:

GinzburgLandau