desc.coils.FourierXYZCoil.compute_magnetic_vector_potential

FourierXYZCoil.compute_magnetic_vector_potential(coords, params=None, basis='rpz', source_grid=None, transforms=None, chunk_size=None)Source

Compute magnetic vector potential at a set of points.

The coil current may be overridden by including current in the params dictionary.

Parameters:

  • coords (array-like shape(n,3)) – Nodes to evaluate field at in [R,phi,Z] or [X,Y,Z] coordinates.

  • params (dict, optional) – Parameters to pass to Curve.

  • basis ({"rpz", "xyz"}) – Basis for input coordinates and returned magnetic field.

  • source_grid (Grid, int or None, optional) – Grid used to discretize coil. If an integer, uses that many equally spaced points. Should NOT include endpoint at 2pi.

  • transforms (dict of Transform or array-like) – Transforms for R, Z, lambda, etc. Default is to build from grid.

  • chunk_size (int or None) – Size to split computation into chunks of evaluation points. If no chunking should be done or the chunk size is the full input then supply None. Default is None.

Returns:

vector_potential (ndarray, shape(n,3)) –

Magnetic vector potential at specified points, in either rpz or

xyz coordinates.

Notes

Uses direct quadrature of the Biot-Savart integral for filamentary coils with tangents provided by the underlying curve class. Convergence should be exponential in the number of points used to discretize the curve, though curl(B) may not be zero if not fully converged.