lsst.pipe.tasks.extended_psf.StackBrightStarsTask Class Reference

Inheritance diagram for lsst.pipe.tasks.extended_psf.StackBrightStarsTask:

Public Member Functions
def	__init__ (self, initInputs=None, *args, **kwargs)
def	run (self, bss_ref_list, region_name=None)

Static Public Attributes
	ConfigClass = StackBrightStarsConfig

Detailed Description

Stack bright stars together to build an extended PSF model.

Definition at line 311 of file extended_psf.py.

Constructor & Destructor Documentation

__init__()

def lsst.pipe.tasks.extended_psf.StackBrightStarsTask.__init__	(		self,
			initInputs = None,
		*	args,
		**	kwargs
	)

Definition at line 317 of file extended_psf.py.

    def __init__(self, initInputs=None, *args, **kwargs):
        pipeBase.CmdLineTask.__init__(self, *args, **kwargs)
 

Member Function Documentation

run()

def lsst.pipe.tasks.extended_psf.StackBrightStarsTask.run	(		self,
			bss_ref_list,
			region_name = None
	)

Read input bright star stamps and stack them together.

The stacking is done iteratively over smaller areas of the final model
image to allow for a great number of bright star stamps to be used.

Parameters
----------
bss_ref_list : `list` of
        `lsst.daf.butler._deferredDatasetHandle.DeferredDatasetHandle`
    List of available bright star stamps data references.
region_name : `str`, optional
    Name of the focal plane region, if applicable. Only used for
    logging purposes, when running over multiple such regions
    (typically from `MeasureExtendedPsfTask`)

Definition at line 334 of file extended_psf.py.

    def run(self, bss_ref_list, region_name=None):
        """Read input bright star stamps and stack them together.
 
        The stacking is done iteratively over smaller areas of the final model
        image to allow for a great number of bright star stamps to be used.
 
        Parameters
        ----------
        bss_ref_list : `list` of
                `lsst.daf.butler._deferredDatasetHandle.DeferredDatasetHandle`
            List of available bright star stamps data references.
        region_name : `str`, optional
            Name of the focal plane region, if applicable. Only used for
            logging purposes, when running over multiple such regions
            (typically from `MeasureExtendedPsfTask`)
        """
        if region_name:
            region_message = f' for region "{region_name}".'
        else:
            region_message = ''
        self.log.info('Building extended PSF from stamps extracted from %d detector images%s',
                      len(bss_ref_list), region_message)
        # read in example set of full stamps
        example_bss = bss_ref_list[0].get(datasetType="brightStarStamps", immediate=True)
        example_stamp = example_bss[0].stamp_im
        # create model image
        ext_psf = afwImage.MaskedImageF(example_stamp.getBBox())
        # divide model image into smaller subregions
        subregion_size = Extent2I(*self.config.subregion_size)
        sub_bboxes = AssembleCoaddTask._subBBoxIter(ext_psf.getBBox(), subregion_size)
        # compute approximate number of subregions
        n_subregions = int(ext_psf.getDimensions()[0]/subregion_size[0] + 1)*int(
            ext_psf.getDimensions()[1]/subregion_size[1] + 1)
        self.log.info("Stacking will performed iteratively over approximately %d "
                      "smaller areas of the final model image.", n_subregions)
        # set up stacking statistic
        stats_control, stats_flags = self._set_up_stacking(example_stamp)
        # perform stacking
        for jbbox, bbox in enumerate(sub_bboxes):
            all_stars = None
            for bss_ref in bss_ref_list:
                read_stars = bss_ref.get(datasetType="brightStarStamps", parameters={'bbox': bbox})
                if self.config.do_mag_cut:
                    read_stars = read_stars.selectByMag(magMax=self.config.mag_limit)
                if all_stars:
                    all_stars.extend(read_stars)
                else:
                    all_stars = read_stars
            # TODO: DM-27371 add weights to bright stars for stacking
            coadd_sub_bbox = afwMath.statisticsStack(all_stars.getMaskedImages(), stats_flags, stats_control)
            ext_psf.assign(coadd_sub_bbox, bbox)
        return ext_psf
 
 

Member Data Documentation

ConfigClass

lsst.pipe.tasks.extended_psf.StackBrightStarsTask.ConfigClass = StackBrightStarsConfig

static

Definition at line 314 of file extended_psf.py.

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The documentation for this class was generated from the following file:

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-0.7.0/Linux64/pipe_tasks/21.0.0-172-gfb10e10a+18fedfabac/python/lsst/pipe/tasks/extended_psf.py