def _fill_radec(self):
"""Compute RA/Dec columns, if a reference image is specified."""
if self.referenceImagePath is not None:
refHead = getheader(self.referenceImagePath)
wcs = WCS(refHead)
ra, dec = wcs.all_pix2sky(self._gdata['x'], self._gdata['y'], 1)
self._gdata['ra'] = ra
self._gdata['dec'] = dec
else:
self._gdata['ra'][:] = np.nan
self._gdata['dec'][:] = np.nan
