autowisp.piecewise_bicubic_psf_map module

Class Inheritance Diagram

Define class for working with piecewise bucubic PSF maps.

class autowisp.piecewise_bicubic_psf_map.PiecewiseBicubicPSFMap(dr_fname=None)

Bases: object

Fit and use piecewise bicubic PSF maps.

__call__(source)

Evaluate the map for the given source.

Parameters:

source (numpy structured value) – Should specify all variables needed by the map.

Returns:

The PSF of the given source.

Return type:

astrowisp.PiecewiseBicubicPSF

__init__(dr_fname=None)

Create a map, loading it from a DR file if one is specified.

fit(fits_fnames, sources, shape_terms_expression, *, background_annulus=(6.0, 7.0), require_convergence=True, output_dr_fnames=None, dr_path_substitutions, **fit_star_shape_config)

Find the best fit PSF/PRF map for the given images (simultaneous fit).

Parameters:

• fits_fnames (str iterable) – The filenames of the FITS files to fit.

• sources (numpy structured array iterable) – For each image specify the sources on which to base the PSF/PRF map. Sources are supplied as a numpy structured array that should define all variables required to evaluate the shape term expression specified on __init__(). It must also include 'x' and 'y' fields, even if those are not required to evaluate the terms.

• shape_terms_expression (str) – An expression specifying the terms PSF/PRF parameters are allowed to dependend on. May involve arbitrary catalogque position and other external variables. See fit_expression.Interface for details.

• background_annulus (float, float) – The inner radius and difference between inner and outer radius of the annulus around each source where background is measured. See astrowisp.BackgroundExtractor for details.

• require_convergence (bool) – See same name argument to astrowisp.FitStarShape.fit()

• output_dr_fnames (str iterable) – If not None, should specify one data reduction file for each input frame where the fit results are saved.

• background_version (int), shapefit_version(int) srcproj_version(int) – The version numbers to use when saving projected photometry sources, background extraciton, and PSF/PRF fitting results.

• fit_star_shape_config – Any required configuration by astrowisp.FitStarShape.__init__()

Returns:

None

load(dr_fname, return_sources=False, **dr_path_substitutions)

Read the PSF/PRF map from the given data reduction file.