CoordinateGrid

class vspec_vsm.CoordinateGrid

Bases: object

Base class for all coordinate grids.

Attributes:

area

Get the area of each point as a fraction of the unit sphere.

Methods

cos_angle_from_disk_center(lat0, lon0)	Get the cosine of the angle from disk center.
display_grid(nlat, nlon, data)	Resample the data to a rectangular grid.
grid()	Get a grid of latitudes and longitudes.
new(grid_params)	Create an instance of a coordinate grid subclass from a set of parameters.
zeros([dtype])	Get an array of zeros.

Attributes Summary

area	Get the area of each point as a fraction of the unit sphere.

Methods Summary

cos_angle_from_disk_center(lat0, lon0)	Get the cosine of the angle from disk center.
display_grid(nlat, nlon, data)	Resample the data to a rectangular grid.
grid()	Get a grid of latitudes and longitudes.
new(grid_params)	Create an instance of a coordinate grid subclass from a set of parameters.
zeros([dtype])	Get an array of zeros.

Attributes Documentation

area

Get the area of each point as a fraction of the unit sphere.

Returns:

The area of each point.

Return type:

np.ndarray

Methods Documentation

cos_angle_from_disk_center(lat0: astropy.units.Quantity, lon0: astropy.units.Quantity) → ndarray

Get the cosine of the angle from disk center.

Parameters:

• lat0 (astropy.units.Quantity) – The sub-observer latitude.

• lon0 (astropy.units.Quantity) – The sub-observer longitude

Returns:

An array of cos(x) where x is the angle from disk center.

Return type:

np.ndarray

Notes

Recall

\[\mu = \cos{x}\]

Where \(x\) is the angle from center of the disk.

display_grid(nlat: int, nlon: int, data: ndarray | astropy.units.Quantity) → Tuple[ndarray, ndarray, astropy.units.Quantity]

Resample the data to a rectangular grid.

Parameters:

• nlat (int) – Number of latitude points to resample to.

• nlon (int) – Number of longitude points to resample to.

• data (np.ndarray or astropy.units.Quantity) – The data to display.

Returns:

• lat (np.ndarray, shape=(nlat,)) – Array of latitudes.

• lon (np.ndarray, shape=(nlon,)) – Array of longitudes.

• dat (astropy.units.Quantity, shape=(nlat,nlon)) – The resampled data.

grid() → Tuple[astropy.units.Quantity, astropy.units.Quantity]

Get a grid of latitudes and longitudes.

Returns:

• lat (astropy.units.Quantity) – Array of latitudes.

• lon (astropy.units.Quantity) – Array of longitudes.

static new(grid_params: int | Tuple[int, int])

Create an instance of a coordinate grid subclass from a set of parameters.

Parameters:

grid_params (int or tuple) – If a tuple, the first element is the number of latitude points and the second is the number of longitude points. If an int, it is the total number of points.

Returns:

grid – An instance of a coordinate grid subclass. If grid_params is a tuple, the grid is a RectangularGrid. If grid_params is an int, the grid is a SpiralGrid.

Return type:

SpiralGrid or RectangularGrid

Raises:

TypeError – If grid_params is not an int or a tuple.

zeros(dtype: str = 'float32') → ndarray

Get an array of zeros.

Parameters:

dtype (str, default='float32') – Data type to pass to np.zeros.

Returns:

An array of zeros.

Return type:

np.ndarray