compute_coverage

one_pass_fitting.compute_coverage(cat: Table, ref_wcs: WCS, wcs_list: list) → array

Computes how many exposures and seconds cover a catalog of positions in a drizzled frame.

For every position in a catalog corresponding to a drizzled frame, this function returns how many exposures covered that point, and how many seconds of exposure time covered that point. It does this by reconstructing the WCS of every input exposure/extension, and transforming the positions in the catalog to the exposure/extension frame, and seeing if the transformed positions land on the array. It then adds up the exposure time of each exposure, accounting for each exposures coverage of the different positions.

Parameters

catastropy Table

Catalog containing X and Y positions in drizzled frame

Returns

n_expnumpy array

Number of exposures that cover the X and Y positions in cat