desc.equilibrium.Equilibrium.from_near_axis

classmethod Equilibrium.from_near_axis(na_eq, r=0.1, L=None, M=8, N=None, ntheta=None, spectral_indexing='ansi', w=2)Source

Initialize an Equilibrium from a near-axis solution.

Parameters:

  • na_eq (Qsc or Qic) – Near-axis solution generated by pyQSC or pyQIC.

  • r (float) – Radius of the desired boundary surface (in meters).

  • L (int (optional)) – Radial resolution. Default 2*M for spectral_indexing=='fringe', else M

  • M (int (optional)) – Poloidal resolution. Default is 8

  • N (int (optional)) – Toroidal resolution. Default is M. If N=np.inf, the max resolution provided by na_eq.nphi is used.

  • ntheta (int, optional) – Number of poloidal grid points used in the conversion. Default 2*M+1

  • spectral_indexing (str (optional)) – Type of Zernike indexing scheme to use. Default 'ansi'

  • w (float) – Weight exponent for fit. Surfaces are fit using a weighted least squares using weight = 1/rho**w, so that points near axis are captured more accurately.

Returns:

eq (Equilibrium) – Equilibrium approximation of the near-axis solution.