NEDAS.models.ks package

class NEDAS.models.ks.KSModel(**kwargs)[source]

Bases: OdeModel

The Kuramoto-Sivashinsky equation u_t = -u u_x - u_xx - u_xxxx, on a periodic domain of length 32 pi (by default), the simplest PDE with spatio-temporal chaos.

As in DAPPER mods/KS: pseudo-spectral, with the ETD-RK4 scheme of Kassam and Trefethen (2005). The grid is the nx collocation points, so distances are in grid spacings (L / nx).

Parameters:

  • nx (int) – number of grid points

  • DL (float) – domain length in units of pi

cyclic: bool = True
nx: int
DL: float
property state_size: int

length of the state vector

x0() → ndarray[source]

the initial condition of Kassam and Trefethen (2005)

step(x: ndarray) → ndarray[source]

one time step of length dt; RK4 of dxdt unless a subclass has its own scheme

Submodules