Documentation for ScatteredLightBackground

scatterbrain.background.ScatteredLightBackground

Class for working with TESS data to fit and use scattered background models.

ScatteredLightBackground will automatically set up a reasonable background model for you. If you want to tweak the model, check out the design_matrix API.

__getitem__(self, key) special

Set indexing

__init__(self, sector, camera, ccd, column=None, row=None, sigma_f=None, nknots=50, cutout_size=2048, tstart=None, tstop=None, quality=None, verbose=False, njitter=10000, strap_npoly=2) special

Initialize a ScatteredLightBackground object either for fitting or loading a model.

Parameters:

Name	Type	Description	Default
sector	int	Sector number	required
camera	int	Camera number	required
ccd	int	CCD number	required
column	None or xp.ndarray	The column numbers to evaluate the design matrix at. If None, uses all pixels.	None
row	None or xp.ndarray	The column numbers to evaluate the design matrix at. If None, uses all pixels.	None
sigma_f	xp.ndarray	The weights for each pixel in the design matrix. Default is equal weights.	None
nknots	int	Number of knots to for spline matrix	50
cutout_size	int	Size of a "cutout" of images to use. Default is 2048. Use a smaller cut out to test functionality	2048

clean(self)

Resets the weights and average frame

fit_model(self, flux_cube, tstart=None, batch_size=50, test_frame=0, mask_asteroids=False)

Fit a model to a flux cube, fitting frames in batches of size batch_size.

This will append to the list properties self.weights_basic, self.weights_full, self.jitter.

Parameters:

Name	Type	Description	Default
flux_cube	xp.ndarray	3D array of frames.	required
tstart	np.ndarray	Times for each frame. Required if masking asteroids.	None
batch_size	int	Number of frames to fit at once.	50
test_frame	int	The index of the frame to use as the "reference frame". This reference frame will be used to build masks to set sigma_f. It should be the lowest background frame.	0

from_tess_images(fnames, mask_asteroids=True, batch_size=50, test_frame=None, cutout_size=2048, sector=None, camera=None, ccd=None, verbose=False, quality_bitmask=175, njitter=5000) staticmethod

Creates a ScatteredLightBackground model from filenames

Parameters:

Name	Type	Description	Default
fnames	list	List of filenames to compute the background model for	required
batch_size	int	Number of files to process in a given batch	50
test_frame	None or int	The frame to use as a "test" frame for building masks. If None, a reasonable frame will be chosen.	None

Returns:

Type	Description
`scatterbrain.ScatteredLightBackground.ScatteredLightBackground`	ScatteredLightBackground object

load(self, input, dir=None)

Load a model fit to the tess-backrop data directory.

Parameters:

Name	Type	Description	Default
input	tuple or string	Either pass a tuple with (sector, camera, ccd) or pass a file name in dir to load	required
dir	str	Optional tring with the directory name	None

model(self, time_index=None)

Build a model for a frame with index time_index

save(self, output_dir=None, overwrite=False)

Save a model fit to the scatterbrain data directory.