measure_centroid¶
- poppy.measure_centroid(HDUlist_or_filename=None, ext=0, slice=0, boxsize=20, verbose=False, units='pixels', relativeto='origin', **kwargs)[source]¶
Measure the center of an image via center-of-mass
The centroid method used is the floating-box center of mass algorithm by Jeff Valenti et al., which has been adopted for JWST target acquisition measurements on orbit. See JWST technical reports JWST-STScI-001117 and JWST-STScI-001134 for details.
- Parameters:
- HDUlist_or_filenamestring
Either a fits.HDUList object or a filename of a FITS file on disk
- extint
Extension in that FITS file
- sliceint, optional
If that extension is a 3D datacube, which slice (plane) of that datacube to use
- boxsizeint
Half box size for centroid
- relativetostring
either ‘origin’ for relative to pixel (0,0) or ‘center’ for relative to image center. Default is ‘origin’
- unitsstring
either ‘pixels’ for position in pixels or ‘arcsec’ for arcseconds. Relative to the relativeto parameter point in either case.
- verbosebool
Be more verbose
- Returns:
- CoMarray_like
[Y, X] coordinates of center of mass.