pleiades.RectangularCoil

class pleiades.RectangularCoil(r0=1.0, z0=0.0, nr=1, nz=1, dr=0.1, dz=0.1, angle=0.0, **kwargs)[source]

A rectangular cross section coil in the R-Z plane

Parameters:
  • r0 (float) – The R location of the centroid of the coil
  • z0 (float) – The Z location of the centroid of the coil
  • nr (float, optional) – The number of current filaments in the R direction. Defaults to 10.
  • nz (float, optional) – The number of current filaments in the Z direction. Defaults to 10.
  • dr (float, optional) – The distance between current filaments in the R direction. Defaults to 0.01 m
  • dz (float, optional) – The distance between current filaments in the Z direction. Defaults to 0.01 m
  • nhat (iterable of float, optional) – A vector of (dr, dz) representing the orientation of the coil and the ‘local z direction’. This is the direction which applies to nz and dz when constructing current filament locations. The ‘r’ direction is found by the relation nhat x phi_hat = rhat. Defaults to (0, 1) meaning the local z axis is aligned with the global z axis and likewise for the r axis.
  • **kwargs – Any valid keyword arguments for CurrentFilamentSet.
Variables:
  • r0 (float) – The R location of the centroid of the Coil
  • z0 (float) – The Z location of the centroid of the Coil
  • centroid (np.array) – Helper attribue for the R, Z location of the centroid of the Coil
  • nr (float) – The number of current filaments in the R direction. Defaults to 10.
  • nz (float) – The number of current filaments in the Z direction. Defaults to 10.
  • dr (float) – The distance between current filaments in the R direction. Defaults to 0.1 m
  • dz (float) – The distance between current filaments in the Z direction. Defaults to 0.1 m
  • angle (float) – An angle in degrees representing the rotation of the coil and the ‘local z direction’ with respect to the global z axis. This is the direction which applies to nz and dz when constructing current filament locations. Defaults to 0 meaning the local z axis is aligned with the global z axis.
  • verts (np.ndarray) – A 4x2 np.array representing the 4 vertices of the coil (read-only).
  • area (float) – The area of the coil in m^2 (read-only).
  • current_density (float) – The current density in the coil. This is equal to the total current divided by the area (read-only).
BR(current=None, mesh=None)

Compute the radial component of the magnetic field, BR.

Parameters:current (float, optional) – Specify a current value to override the current attribute for calculating the field. Defaults to None, which causes the current attribute to be used for the calculation
Returns:BR
Return type:np.array
BZ(current=None, mesh=None)

Compute the z component of the magnetic field, BZ.

Parameters:current (float, optional) – Specify a current value to override the current attribute for calculating the field. Defaults to None, which causes the current attribute to be used for the calculation
Returns:BZ
Return type:np.array
clone()

Create and return a copy of this coil

gBR(mesh=None)

Compute the Green’s function for the radial magnetic field, BR

Parameters:mesh (ndarray, optional) – An Nx2 array of points representing (R, Z) coordinates at which to calculate BR. Defaults to None, in which case the CurrentFilamentSet.mesh attribute is used.
Returns:gBR – 1D array representing the Green’s function for BR and whose size is equal to the number of mesh.
Return type:ndarray
gBZ(mesh=None)

Compute the Green’s function for the vertical magnetic field, BZ

Parameters:mesh (ndarray, optional) – An Nx2 array of points representing (R, Z) coordinates at which to calculate BZ. Defaults to None, in which case the CurrentFilamentSet.mesh attribute is used.
Returns:gBZ – 1D array representing the Green’s function for BZ and whose size is equal to the number of mesh.
Return type:ndarray
gpsi(mesh=None)

Compute the Green’s function for magnetic flux, \(psi\).

Parameters:mesh (ndarray, optional) – An Nx2 array of points representing (R, Z) coordinates at which to calculate the magnetic flux. Defaults to None, in which case the CurrentFilamentSet.mesh attribute is used.
Returns:gpsi – 1D array representing the Green’s function for flux and whose size is equal to the number of mesh.
Return type:ndarray
plot(ax, plot_patch=True, **kwargs)

Plot the current locations for the CurrentGroup

Parameters:
  • ax (matplotlib.Axes object) – The axes object for plotting the current locations
  • plot_patch (bool) – Whether to add the patch for this CurrentFilament to the axes.
  • **kwargs (dict, optional) – Keyword arguments to pass to Current.plot method
psi(current=None, mesh=None)

Compute the magnetic flux, \(psi\).

Parameters:
  • current (float, optional) – Specify a current value in amps to use instead of CurrentFilamentSet.current. Defaults to None, in which case the current attribute is used to calculate the flux.
  • mesh (ndarray, optional) – An Nx2 array of points representing (R, Z) coordinates at which to calculate the magnetic flux. Defaults to None, in which case the CurrentFilamentSet.mesh attribute is used.
Returns:

psi
Return type:

ndarray
rotate(angle, pivot=(0.0, 0.0))[source]

Rotate the current group by a given angle around a specified pivot

Parameters:
  • angle (float) – The angle of the rotation in degrees as measured from the z axis
  • pivot (iterable of float, optional) – The (R, Z) location of the pivot. Defaults to (0., 0.).
simplify()

Create a single coil object from weighted sum of current centroids.

translate(vector)[source]

Translate the current group by the vector (dr, dz)

Parameters:vector (iterable of float) – The displacement vector for the translation