measure_radius_at_ee¶

poppy.measure_radius_at_ee(hdulist_or_filename=None, ext=0, center=None, binsize=None, normalize='None')[source]¶

measure encircled energy vs radius and return as an interpolator Returns a function object which when called returns the radius for a given Encircled Energy. This is the inverse function of measure_ee

Parameters:

hdulist_or_filenamestring: Either a fits.HDUList object or a filename of a FITS file on disk
extint: Extension in that FITS file
centertuple of floats: Coordinates (x,y) of PSF center. Default is image center.
binsize:: size of step for profile. Default is pixel size.
normalizestring: set to ‘peak’ to normalize peak intensity =1, or to ‘total’ to normalize total flux=1. Default is no normalization (i.e. retain whatever normalization was used in computing the PSF itself)

Returns:

radius: function: A function which will return the radius of a desired encircled energy.

Examples

>>> ee = measure_radius_at_ee("someimage.fits")  
>>> print("The EE is 50% at {} arcsec".format(ee(0.5)))  