lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask Class Reference

Inheritance diagram for lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask:

Public Member Functions
	__init__ (self, *args, **kwargs)
	selectSources (self, sourceCat, matches=None, exposure=None)

Public Attributes
	parentKey
	nChildKey
	centroidXKey
	centroidYKey
	centroidXErrKey
	centroidYErrKey
	centroidFlagKey
	primaryKey
	edgeKey
	interpolatedCenterKey
	saturatedKey
	instFluxKey
	fluxFlagKey
	instFluxErrKey

Static Public Attributes
	ConfigClass = AstrometrySourceSelectorConfig

Protected Member Functions
	_getSchemaKeys (self, schema)
	_isMultiple (self, sourceCat)
	_hasCentroid (self, sourceCat)
	_goodSN (self, sourceCat)
	_isUsable (self, sourceCat)
	_isPrimary (self, sourceCat)
	_isGood (self, sourceCat)
	_isBadFlagged (self, source)

Detailed Description

Select sources that are useful for astrometry.

Good astrometry sources have high signal/noise, are non-blended, and
did not have certain "bad" flags set during source extraction. They need not
be PSF sources, just have reliable centroids.

Definition at line 72 of file astrometrySourceSelector.py.

Constructor & Destructor Documentation

__init__()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.__init__	(		self,
		*	args,
		**	kwargs )

Reimplemented from lsst.meas.algorithms.sourceSelector.BaseSourceSelectorTask.

Definition at line 81 of file astrometrySourceSelector.py.

    def __init__(self, *args, **kwargs):
        BaseSourceSelectorTask.__init__(self, *args, **kwargs)
 

Member Function Documentation

_getSchemaKeys()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._getSchemaKeys ( self, schema )

protected

Extract and save the necessary keys from schema with asKey.

Definition at line 112 of file astrometrySourceSelector.py.

    def _getSchemaKeys(self, schema):
        """Extract and save the necessary keys from schema with asKey.
        """
        self.parentKey = schema["parent"].asKey()
        self.nChildKey = schema["deblend_nChild"].asKey()
        self.centroidXKey = schema["slot_Centroid_x"].asKey()
        self.centroidYKey = schema["slot_Centroid_y"].asKey()
        self.centroidXErrKey = schema["slot_Centroid_xErr"].asKey()
        self.centroidYErrKey = schema["slot_Centroid_yErr"].asKey()
        self.centroidFlagKey = schema["slot_Centroid_flag"].asKey()
        try:
            self.primaryKey = schema["detect_isPrimary"].asKey()
        except NotFoundError:
            self.primaryKey = None
 
        self.edgeKey = schema["base_PixelFlags_flag_edge"].asKey()
        self.interpolatedCenterKey = schema["base_PixelFlags_flag_interpolatedCenter"].asKey()
        self.saturatedKey = schema["base_PixelFlags_flag_saturated"].asKey()
 
        fluxPrefix = "slot_%sFlux_" % (self.config.sourceFluxType,)
        self.instFluxKey = schema[fluxPrefix + "instFlux"].asKey()
        self.fluxFlagKey = schema[fluxPrefix + "flag"].asKey()
        self.instFluxErrKey = schema[fluxPrefix + "instFluxErr"].asKey()
 

_goodSN()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._goodSN ( self, sourceCat )

protected

Return True for each source that has Signal/Noise > config.minSnr.

Definition at line 160 of file astrometrySourceSelector.py.

    def _goodSN(self, sourceCat):
        """Return True for each source that has Signal/Noise > config.minSnr.
        """
        if self.config.minSnr <= 0:
            return True
        else:
            with np.errstate(invalid="ignore"):  # suppress NAN warnings
                return sourceCat[self.instFluxKey]/sourceCat[self.instFluxErrKey] > self.config.minSnr
 

_hasCentroid()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._hasCentroid ( self, sourceCat )

protected

Return True for each source that has a valid centroid

Definition at line 146 of file astrometrySourceSelector.py.

    def _hasCentroid(self, sourceCat):
        """Return True for each source that has a valid centroid
        """
        def checkNonfiniteCentroid():
            """Return True for sources with non-finite centroids.
            """
            return ~np.isfinite(sourceCat[self.centroidXKey]) | \
                ~np.isfinite(sourceCat[self.centroidYKey])
        assert ~checkNonfiniteCentroid().any(), \
            "Centroids not finite for %d unflagged sources." % (checkNonfiniteCentroid().sum())
        return np.isfinite(sourceCat[self.centroidXErrKey]) \
            & np.isfinite(sourceCat[self.centroidYErrKey]) \
            & ~sourceCat[self.centroidFlagKey]
 

_isBadFlagged()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._isBadFlagged ( self, source )

protected

Return True if any of config.badFlags are set for this source.

Definition at line 209 of file astrometrySourceSelector.py.

    def _isBadFlagged(self, source):
        """Return True if any of config.badFlags are set for this source.
        """
        return any(source[flag] for flag in self.config.badFlags)

_isGood()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._isGood ( self, sourceCat )

protected

Return True for each source that is usable for matching and likely has a
good centroid.

The additional tests for a good centroid, beyond isUsable, are:
- not interpolated in the center
- not saturated
- not near the edge

Definition at line 193 of file astrometrySourceSelector.py.

    def _isGood(self, sourceCat):
        """Return True for each source that is usable for matching and likely has a
        good centroid.
 
        The additional tests for a good centroid, beyond isUsable, are:
        - not interpolated in the center
        - not saturated
        - not near the edge
        """
 
        return self._isUsable(sourceCat) \
            & self._isPrimary(sourceCat) \
            & ~sourceCat[self.saturatedKey] \
            & ~sourceCat[self.interpolatedCenterKey] \
            & ~sourceCat[self.edgeKey]
 

_isMultiple()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._isMultiple ( self, sourceCat )

protected

Return True for each source that is likely multiple sources.

Definition at line 136 of file astrometrySourceSelector.py.

    def _isMultiple(self, sourceCat):
        """Return True for each source that is likely multiple sources.
        """
        test = (sourceCat[self.parentKey] != 0) | (sourceCat[self.nChildKey] != 0)
        # have to currently manage footprints on a source-by-source basis.
        for i, cat in enumerate(sourceCat):
            footprint = cat.getFootprint()
            test[i] |= (footprint is not None) and (len(footprint.getPeaks()) > 1)
        return test
 

_isPrimary()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._isPrimary ( self, sourceCat )

protected

Return True if this is a primary source.

Definition at line 185 of file astrometrySourceSelector.py.

    def _isPrimary(self, sourceCat):
        """Return True if this is a primary source.
        """
        if self.primaryKey:
            return sourceCat[self.primaryKey]
        else:
            return np.ones(len(sourceCat), dtype=bool)
 

_isUsable()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask._isUsable ( self, sourceCat )

protected

Return True for each source that is usable for matching, even if it may
have a poor centroid.

For a source to be usable it must:
- have a valid centroid
- not be deblended
- have a valid flux (of the type specified in this object's constructor)
- have adequate signal-to-noise

Definition at line 169 of file astrometrySourceSelector.py.

    def _isUsable(self, sourceCat):
        """Return True for each source that is usable for matching, even if it may
        have a poor centroid.
 
        For a source to be usable it must:
        - have a valid centroid
        - not be deblended
        - have a valid flux (of the type specified in this object's constructor)
        - have adequate signal-to-noise
        """
 
        return self._hasCentroid(sourceCat) \
            & ~self._isMultiple(sourceCat) \
            & self._goodSN(sourceCat) \
            & ~sourceCat[self.fluxFlagKey]
 

selectSources()

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.selectSources	(		self,
			sourceCat,
			matches = None,
			exposure = None )

Return a selection of sources that are useful for astrometry.

Parameters
----------
sourceCat : `lsst.afw.table.SourceCatalog`
    Catalog of sources to select from.
    This catalog must be contiguous in memory.
matches : `list` of `lsst.afw.table.ReferenceMatch` or None
    Ignored in this SourceSelector.
exposure : `lsst.afw.image.Exposure` or None
    The exposure the catalog was built from; used for debug display.

Returns
-------
struct : `lsst.pipe.base.Struct`
    The struct contains the following data:

    ``selected``
        Boolean array of sources that were selected, same length as
        sourceCat. (`numpy.ndarray` of `bool`)

Reimplemented from lsst.meas.algorithms.sourceSelector.BaseSourceSelectorTask.

Definition at line 84 of file astrometrySourceSelector.py.

    def selectSources(self, sourceCat, matches=None, exposure=None):
        """Return a selection of sources that are useful for astrometry.
 
        Parameters
        ----------
        sourceCat : `lsst.afw.table.SourceCatalog`
            Catalog of sources to select from.
            This catalog must be contiguous in memory.
        matches : `list` of `lsst.afw.table.ReferenceMatch` or None
            Ignored in this SourceSelector.
        exposure : `lsst.afw.image.Exposure` or None
            The exposure the catalog was built from; used for debug display.
 
        Returns
        -------
        struct : `lsst.pipe.base.Struct`
            The struct contains the following data:
 
            ``selected``
                Boolean array of sources that were selected, same length as
                sourceCat. (`numpy.ndarray` of `bool`)
        """
        self._getSchemaKeys(sourceCat.schema)
 
        bad = reduce(lambda x, y: np.logical_or(x, sourceCat[y]), self.config.badFlags, False)
        good = self._isGood(sourceCat)
        return Struct(selected=good & ~bad)
 

Member Data Documentation

centroidFlagKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.centroidFlagKey

Definition at line 121 of file astrometrySourceSelector.py.

centroidXErrKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.centroidXErrKey

Definition at line 119 of file astrometrySourceSelector.py.

centroidXKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.centroidXKey

Definition at line 117 of file astrometrySourceSelector.py.

centroidYErrKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.centroidYErrKey

Definition at line 120 of file astrometrySourceSelector.py.

centroidYKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.centroidYKey

Definition at line 118 of file astrometrySourceSelector.py.

ConfigClass

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.ConfigClass = AstrometrySourceSelectorConfig

static

Definition at line 79 of file astrometrySourceSelector.py.

edgeKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.edgeKey

Definition at line 127 of file astrometrySourceSelector.py.

fluxFlagKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.fluxFlagKey

Definition at line 133 of file astrometrySourceSelector.py.

instFluxErrKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.instFluxErrKey

Definition at line 134 of file astrometrySourceSelector.py.

instFluxKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.instFluxKey

Definition at line 132 of file astrometrySourceSelector.py.

interpolatedCenterKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.interpolatedCenterKey

Definition at line 128 of file astrometrySourceSelector.py.

nChildKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.nChildKey

Definition at line 116 of file astrometrySourceSelector.py.

parentKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.parentKey

Definition at line 115 of file astrometrySourceSelector.py.

primaryKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.primaryKey

Definition at line 123 of file astrometrySourceSelector.py.

saturatedKey

lsst.meas.algorithms.astrometrySourceSelector.AstrometrySourceSelectorTask.saturatedKey

Definition at line 129 of file astrometrySourceSelector.py.

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/meas_algorithms/ge6526c86ff+0d71447b4b/python/lsst/meas/algorithms/astrometrySourceSelector.py