StokesSpectralCube

class spectral_cube.StokesSpectralCube(stokes_data, mask=None, meta=None, fill_value=None)

Bases: object

A class to store a spectral cube with multiple Stokes parameters.

The individual Stokes cubes can share a common mask in addition to having component-specific masks.

Attributes Summary

components
mask	The underlying mask
read
shape
stokes_data	The underlying data
stokes_type	Defines the type of stokes that has been setup. stokes_type can be sky, linear, circular, generic, or other.
wcs
write

Methods Summary

transform_basis([stokes_basis])	The goal of this function is to transform the stokes basis of the cube to the one specified if possible.
with_mask(mask[, inherit_mask])	Return a new StokesSpectralCube instance that contains a composite mask of the current StokesSpectralCube and the new mask.
with_spectral_unit(unit, **kwargs)

Attributes Documentation

components

mask

The underlying mask

read = <spectral_cube.io.core.StokesSpectralCubeRead object>

shape

stokes_data

The underlying data

stokes_type

Defines the type of stokes that has been setup. stokes_type can be sky, linear, circular, generic, or other.

• Sky refers to stokes in sky basis, I,Q,U,V

• Linear refers to the stokes in linear feed basis, XX, XY, YX, YY

• Circular refers to stokes in circular feed basis, RR, RL, LR, LL

• Generic refers to the general four orthogonal components, PP, PQ, QP, QQ

wcs

write = <spectral_cube.io.core.StokesSpectralCubeWrite object>

Methods Documentation

transform_basis(stokes_basis='')

The goal of this function is to transform the stokes basis of the cube to the one specified if possible. In principle one needs at least two related stokes of a given basis for the transformation to be possible. At this moment we are limiting it to the cases where all four stokes parameters in a given basis be available within the cube. The transformations are as follows Linear to Sky I = (XX + YY) / 2 Q = (XX - YY) / 2 U = (XY + YX) / 2 V = 1j(XY - YX) / 2

Circular to Sky I = (RR + LL) / 2 Q = (RL + LR) / 2 U = 1j*(RL - LR) / 2 V = (RR - LL) / 2

with_mask(mask, inherit_mask=True)

Return a new StokesSpectralCube instance that contains a composite mask of the current StokesSpectralCube and the new mask.

Parameters

maskMaskBase instance, or boolean numpy array

The mask to apply. If a boolean array is supplied, it will be converted into a mask, assuming that True values indicate included elements.

inherit_maskbool (optional, default=True)

If True, combines the provided mask with the mask currently attached to the cube

Returns

new_cubeStokesSpectralCube

A cube with the new mask applied.

Notes

This operation returns a view into the data, and not a copy.

with_spectral_unit(unit, **kwargs)