lsst::ip::diffim::PsfDipoleFlux Class Reference

Implementation of Psf dipole flux. More...

#include <DipoleAlgorithms.h>

Inheritance diagram for lsst::ip::diffim::PsfDipoleFlux:

Public Types
typedef PsfDipoleFluxControl	Control
typedef meas::base::FluxResultKey	ResultKey

Public Member Functions
	PsfDipoleFlux (PsfDipoleFluxControl const &ctrl, std::string const &name, afw::table::Schema &schema)
std::pair< double, int >	chi2 (afw::table::SourceRecord &source, afw::image::Exposure< float > const &exposure, double negCenterX, double negCenterY, double negFlux, double posCenterX, double poCenterY, double posFlux) const
void	measure (afw::table::SourceRecord &measRecord, afw::image::Exposure< float > const &exposure) const
	Called to measure a single child source in an image.
void	fail (afw::table::SourceRecord &measRecord, meas::base::MeasurementError *error=NULL) const
	Handle an exception thrown by the current algorithm by setting flags in the given record.
ResultKey const &	getPositiveKeys () const
	Return the standard flux keys registered by this algorithm.
ResultKey const &	getNegativeKeys () const
void	measureForced (afw::table::SourceRecord &measRecord, afw::image::Exposure< float > const &exposure, afw::table::SourceRecord const &refRecord, afw::geom::SkyWcs const &refWcs) const override
	Called to measure a single child source in an image.
void	measureNForced (afw::table::SourceCatalog const &measCat, afw::image::Exposure< float > const &exposure, afw::table::SourceCatalog const &refRecord, afw::geom::SkyWcs const &refWcs) const override
	Called to simultaneously measure all children in a deblend family, in a single image.
virtual void	measureN (afw::table::SourceCatalog const &measCat, afw::image::Exposure< float > const &exposure) const
	Called to simultaneously measure all children in a deblend family, in a single image.
std::string	getLogName () const

Static Public Member Functions
static meas::base::FlagDefinitionList const &	getFlagDefinitions ()

Static Public Attributes
static meas::base::FlagDefinition const	FAILURE = dipoleFluxFlagDefinitions.addFailureFlag("general failure flag, set if anything went wrong")
static meas::base::FlagDefinition const	POS_FLAG = dipoleFluxFlagDefinitions.add("pos_flag", "failure flag for positive, set if anything went wrong")
static meas::base::FlagDefinition const	NEG_FLAG = dipoleFluxFlagDefinitions.add("neg_flag", "failure flag for negative, set if anything went wrong")

Protected Attributes
meas::base::FluxResultKey	_fluxResultKey
meas::base::FlagHandler	_flagHandler
ResultKey	_positiveKeys
ResultKey	_negativeKeys
std::string	_logName

Detailed Description

Implementation of Psf dipole flux.

Definition at line 293 of file DipoleAlgorithms.h.

Member Typedef Documentation

Control

typedef PsfDipoleFluxControl lsst::ip::diffim::PsfDipoleFlux::Control

Definition at line 296 of file DipoleAlgorithms.h.

ResultKey

typedef meas::base::FluxResultKey lsst::ip::diffim::DipoleFluxAlgorithm::ResultKey

inherited

Definition at line 131 of file DipoleAlgorithms.h.

Constructor & Destructor Documentation

PsfDipoleFlux()

lsst::ip::diffim::PsfDipoleFlux::PsfDipoleFlux ( PsfDipoleFluxControl const & ctrl, std::string const & name, afw::table::Schema & schema )

inline

Definition at line 298 of file DipoleAlgorithms.h.

                                                                                                      :
        DipoleFluxAlgorithm(ctrl, name, schema, "jointly fitted psf flux counts"),
        _ctrl(ctrl),
        _chi2dofKey(schema.addField<float>(name+"_chi2dof",
                                           "chi2 per degree of freedom of fit"))
    {
        meas::base::CentroidResultKey::addFields(schema, name+"_pos_centroid", "psf fitted center of positive lobe", meas::base::SIGMA_ONLY);
        meas::base::CentroidResultKey::addFields(schema, name+"_neg_centroid", "psf fitted center of negative lobe", meas::base::SIGMA_ONLY);
        meas::base::CentroidResultKey::addFields(schema, name, "average of negative and positive lobe positions", meas::base::SIGMA_ONLY);
        _posCentroid = meas::base::CentroidResultKey(schema[name+"_pos_centroid"]);
        _negCentroid = meas::base::CentroidResultKey(schema[name+"_neg_centroid"]);
        _avgCentroid = meas::base::CentroidResultKey(schema[name]);
    }

Member Function Documentation

chi2()

std::pair< double, int > lsst::ip::diffim::PsfDipoleFlux::chi2	(	afw::table::SourceRecord &	source,
		afw::image::Exposure< float > const &	exposure,
		double	negCenterX,
		double	negCenterY,
		double	negFlux,
		double	posCenterX,
		double	poCenterY,
		double	posFlux ) const

Definition at line 351 of file DipoleAlgorithms.cc.

        {
 
    geom::Point2D negCenter(negCenterX, negCenterY);
    geom::Point2D posCenter(posCenterX, posCenterY);
 
    std::shared_ptr<afw::detection::Footprint const> footprint = source.getFootprint();
 
    /*
     * Fit for the superposition of Psfs at the two centroids.
     */
    std::shared_ptr<afwDet::Psf const> psf = exposure.getPsf();
    std::shared_ptr<afwImage::Image<afwMath::Kernel::Pixel>> negPsf = psf->computeImage(negCenter);
    std::shared_ptr<afwImage::Image<afwMath::Kernel::Pixel>> posPsf = psf->computeImage(posCenter);
 
    afwImage::Image<double> negModel(footprint->getBBox());
    afwImage::Image<double> posModel(footprint->getBBox());
    afwImage::Image<float> data(*(exposure.getMaskedImage().getImage()),footprint->getBBox());
    afwImage::Image<afwImage::VariancePixel> var(*(exposure.getMaskedImage().getVariance()),
                                                 footprint->getBBox());
 
    geom::Box2I negPsfBBox = negPsf->getBBox();
    geom::Box2I posPsfBBox = posPsf->getBBox();
    geom::Box2I negModelBBox = negModel.getBBox();
    geom::Box2I posModelBBox = posModel.getBBox();
 
    // Portion of the negative Psf that overlaps the model
    int negXmin = std::max(negPsfBBox.getMinX(), negModelBBox.getMinX());
    int negYmin = std::max(negPsfBBox.getMinY(), negModelBBox.getMinY());
    int negXmax = std::min(negPsfBBox.getMaxX(), negModelBBox.getMaxX());
    int negYmax = std::min(negPsfBBox.getMaxY(), negModelBBox.getMaxY());
    geom::Box2I negBBox = geom::Box2I(geom::Point2I(negXmin, negYmin),
                                      geom::Point2I(negXmax, negYmax));
    afwImage::Image<afwMath::Kernel::Pixel> negSubim(*negPsf, negBBox);
    afwImage::Image<double> negModelSubim(negModel, negBBox);
    negModelSubim += negSubim;
 
    // Portion of the positive Psf that overlaps the model
    int posXmin = std::max(posPsfBBox.getMinX(), posModelBBox.getMinX());
    int posYmin = std::max(posPsfBBox.getMinY(), posModelBBox.getMinY());
    int posXmax = std::min(posPsfBBox.getMaxX(), posModelBBox.getMaxX());
    int posYmax = std::min(posPsfBBox.getMaxY(), posModelBBox.getMaxY());
    geom::Box2I posBBox = geom::Box2I(geom::Point2I(posXmin, posYmin),
                                      geom::Point2I(posXmax, posYmax));
    afwImage::Image<afwMath::Kernel::Pixel> posSubim(*posPsf, posBBox);
    afwImage::Image<double> posModelSubim(posModel, posBBox);
    posModelSubim += posSubim;
 
    negModel  *= negFlux;   // scale negative model to image
    posModel  *= posFlux;   // scale positive model to image
    afwImage::Image<double> residuals(negModel, true); // full model contains negative lobe...
    residuals += posModel;  // plus positive lobe...
    residuals -= data;      // minus the data...
    residuals *= residuals; // squared...
    residuals /= var;       // divided by the variance : [(model-data)/sigma]**2
    afwMath::Statistics stats = afwMath::makeStatistics(residuals, afwMath::SUM | afwMath::NPOINT);
    double chi2 = stats.getValue(afwMath::SUM);
    int nPix = stats.getValue(afwMath::NPOINT);
    return std::pair<double,int>(chi2, nPix);
}

fail()

void lsst::ip::diffim::PsfDipoleFlux::fail ( afw::table::SourceRecord & measRecord, meas::base::MeasurementError * error = NULL ) const

virtual

Handle an exception thrown by the current algorithm by setting flags in the given record.

fail() is called by the measurement framework when an exception is allowed to propagate out of one the algorithm's measure() methods. It should generally set both a general failure flag for the algorithm as well as a specific flag indicating the error condition, if possible. To aid in this, if the exception was an instance of MeasurementError, it will be passed in, carrying information about what flag to set.

An algorithm can also to chose to set flags within its own measure() methods, and then just return, rather than throw an exception. However, fail() should be implemented even when all known failure modes do not throw exceptions, to ensure that unexpected exceptions thrown in lower-level code are properly handled.

Implements lsst::meas::base::BaseAlgorithm.

Definition at line 512 of file DipoleAlgorithms.cc.

                                                                                                  {
    _flagHandler.handleFailure(measRecord, error);
}

getFlagDefinitions()

meas::base::FlagDefinitionList const & lsst::ip::diffim::DipoleFluxAlgorithm::getFlagDefinitions ( )

staticinherited

Definition at line 65 of file DipoleAlgorithms.cc.

                                                                           {
    return dipoleFluxFlagDefinitions;
}

getLogName()

std::string lsst::meas::base::BaseAlgorithm::getLogName ( ) const

inlineinherited

Definition at line 66 of file Algorithm.h.

{ return _logName; }

getNegativeKeys()

ResultKey const & lsst::ip::diffim::DipoleFluxAlgorithm::getNegativeKeys ( ) const

inlineinherited

Definition at line 134 of file DipoleAlgorithms.h.

{ return _negativeKeys; }

getPositiveKeys()

ResultKey const & lsst::ip::diffim::DipoleFluxAlgorithm::getPositiveKeys ( ) const

inlineinherited

Return the standard flux keys registered by this algorithm.

Definition at line 133 of file DipoleAlgorithms.h.

{ return _positiveKeys; }

measure()

void lsst::ip::diffim::PsfDipoleFlux::measure ( afw::table::SourceRecord & measRecord, afw::image::Exposure< float > const & exposure ) const

virtual

Called to measure a single child source in an image.

Before this method is called, all neighbors will be replaced with noise, using the outputs of the deblender. Outputs should be saved in the given SourceRecord, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

Implements lsst::meas::base::SingleFrameAlgorithm.

Definition at line 416 of file DipoleAlgorithms.cc.

        {
 
    typedef afw::image::Exposure<float>::MaskedImageT MaskedImageT;
 
    std::shared_ptr<afw::detection::Footprint const> footprint = source.getFootprint();
    if (!footprint) {
        throw LSST_EXCEPT(pex::exceptions::RuntimeError,
                          (boost::format("No footprint for source %d") % source.getId()).str());
    }
 
    afw::detection::PeakCatalog peakCatalog = afw::detection::PeakCatalog(footprint->getPeaks());
 
    if (peakCatalog.size() == 0) {
        throw LSST_EXCEPT(pex::exceptions::RuntimeError,
                          (boost::format("No peak for source %d") % source.getId()).str());
    }
    else if (peakCatalog.size() == 1) {
        // No deblending to do
        return;
    }
 
    // For N>=2, just measure the brightest-positive and brightest-negative
    // peaks.  peakCatalog is automatically ordered by peak flux, with the most
    // positive one (brightest) being first
    afw::detection::PeakRecord const& positivePeak = peakCatalog.front();
    afw::detection::PeakRecord const& negativePeak = peakCatalog.back();
 
    // Set up fit parameters and param names
    ROOT::Minuit2::MnUserParameters fitPar;
 
    fitPar.Add((boost::format("P%d")%NEGCENTXPAR).str(), negativePeak.getFx(), _ctrl.stepSizeCoord);
    fitPar.Add((boost::format("P%d")%NEGCENTYPAR).str(), negativePeak.getFy(), _ctrl.stepSizeCoord);
    fitPar.Add((boost::format("P%d")%NEGFLUXPAR).str(), negativePeak.getPeakValue(), _ctrl.stepSizeFlux);
    fitPar.Add((boost::format("P%d")%POSCENTXPAR).str(), positivePeak.getFx(), _ctrl.stepSizeCoord);
    fitPar.Add((boost::format("P%d")%POSCENTYPAR).str(), positivePeak.getFy(), _ctrl.stepSizeCoord);
    fitPar.Add((boost::format("P%d")%POSFLUXPAR).str(), positivePeak.getPeakValue(), _ctrl.stepSizeFlux);
 
    // Create the minuit object that knows how to minimise our functor
    //
    MinimizeDipoleChi2 minimizerFunc(*this, source, exposure);
    minimizerFunc.setErrorDef(_ctrl.errorDef);
 
    //
    // tell minuit about it
    //
    ROOT::Minuit2::MnMigrad migrad(minimizerFunc, fitPar);
 
    //
    // And let it loose
    //
    ROOT::Minuit2::FunctionMinimum min = migrad(_ctrl.maxFnCalls);
 
    float minChi2 = min.Fval();
    bool const isValid = min.IsValid() && std::isfinite(minChi2);
 
    if (true || isValid) {              // calculate coeffs even in minuit is unhappy
 
        /* I need to call chi2 one more time to grab nPix to calculate chi2/dof.
           Turns out that the Minuit operator method has to be const, and the
           measurement _apply method has to be const, so I can't store nPix as a
           private member variable anywhere.  Consted into a corner.
        */
        std::pair<double,int> fit = chi2(source, exposure,
                                         min.UserState().Value(NEGCENTXPAR),
                                         min.UserState().Value(NEGCENTYPAR),
                                         min.UserState().Value(NEGFLUXPAR),
                                         min.UserState().Value(POSCENTXPAR),
                                         min.UserState().Value(POSCENTYPAR),
                                         min.UserState().Value(POSFLUXPAR));
        double evalChi2 = fit.first;
        int nPix = fit.second;
 
        std::shared_ptr<geom::Point2D> minNegCentroid(new geom::Point2D(min.UserState().Value(NEGCENTXPAR),
                                                            min.UserState().Value(NEGCENTYPAR)));
        source.set(getNegativeKeys().getInstFlux(), min.UserState().Value(NEGFLUXPAR));
        source.set(getNegativeKeys().getInstFluxErr(), min.UserState().Error(NEGFLUXPAR));
 
        std::shared_ptr<geom::Point2D> minPosCentroid(new geom::Point2D(min.UserState().Value(POSCENTXPAR),
                                                            min.UserState().Value(POSCENTYPAR)));
        source.set(getPositiveKeys().getInstFlux(), min.UserState().Value(POSFLUXPAR));
        source.set(getPositiveKeys().getInstFluxErr(), min.UserState().Error(POSFLUXPAR));
 
        source.set(_chi2dofKey, evalChi2 / (nPix - minimizerFunc.getNpar()));
        source.set(_negCentroid.getX(), minNegCentroid->getX());
        source.set(_negCentroid.getY(), minNegCentroid->getY());
        source.set(_posCentroid.getX(), minPosCentroid->getX());
        source.set(_posCentroid.getY(), minPosCentroid->getY());
        source.set(_avgCentroid.getX(), 0.5*(minNegCentroid->getX() + minPosCentroid->getX()));
        source.set(_avgCentroid.getY(), 0.5*(minNegCentroid->getY() + minPosCentroid->getY()));
 
    }
}

measureForced()

void lsst::meas::base::SimpleAlgorithm::measureForced ( afw::table::SourceRecord & measRecord, afw::image::Exposure< float > const & exposure, afw::table::SourceRecord const & refRecord, afw::geom::SkyWcs const & refWcs ) const

inlineoverridevirtualinherited

Called to measure a single child source in an image.

Before this method is called, all neighbors will be replaced with noise, using the outputs of the deblender. Outputs should be saved in the given SourceRecord, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

Implements lsst::meas::base::ForcedAlgorithm.

Reimplemented in lsst::meas::extensions::photometryKron::KronFluxAlgorithm.

Definition at line 172 of file Algorithm.h.

                                                                           {
        measure(measRecord, exposure);
    }

measureN()

void lsst::meas::base::SingleFrameAlgorithm::measureN ( afw::table::SourceCatalog const & measCat, afw::image::Exposure< float > const & exposure ) const

virtualinherited

Called to simultaneously measure all children in a deblend family, in a single image.

Outputs should be saved in the given SourceCatalog, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

The default implementation simply throws an exception, indicating that simultaneous measurement is not supported.

Definition at line 31 of file Algorithm.cc.

                                                                                   {
    throw LSST_EXCEPT(pex::exceptions::LogicError, "measureN not implemented for this algorithm");
}

measureNForced()

void lsst::meas::base::SimpleAlgorithm::measureNForced ( afw::table::SourceCatalog const & measCat, afw::image::Exposure< float > const & exposure, afw::table::SourceCatalog const & refRecord, afw::geom::SkyWcs const & refWcs ) const

inlineoverridevirtualinherited

Called to simultaneously measure all children in a deblend family, in a single image.

Outputs should be saved in the given SourceCatalog, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

The default implementation simply throws an exception, indicating that simultaneous measurement is not supported.

Reimplemented from lsst::meas::base::ForcedAlgorithm.

Definition at line 179 of file Algorithm.h.

                                                                            {
        measureN(measCat, exposure);
    }

Member Data Documentation

_flagHandler

meas::base::FlagHandler lsst::ip::diffim::DipoleFluxAlgorithm::_flagHandler

protectedinherited

Definition at line 145 of file DipoleAlgorithms.h.

_fluxResultKey

meas::base::FluxResultKey lsst::ip::diffim::DipoleFluxAlgorithm::_fluxResultKey

protectedinherited

Definition at line 144 of file DipoleAlgorithms.h.

_logName

std::string lsst::meas::base::BaseAlgorithm::_logName

protectedinherited

Definition at line 69 of file Algorithm.h.

_negativeKeys

ResultKey lsst::ip::diffim::DipoleFluxAlgorithm::_negativeKeys

protectedinherited

Definition at line 148 of file DipoleAlgorithms.h.

_positiveKeys

ResultKey lsst::ip::diffim::DipoleFluxAlgorithm::_positiveKeys

protectedinherited

Definition at line 147 of file DipoleAlgorithms.h.

FAILURE

meas::base::FlagDefinition const lsst::ip::diffim::DipoleFluxAlgorithm::FAILURE = dipoleFluxFlagDefinitions.addFailureFlag("general failure flag, set if anything went wrong")

staticinherited

Definition at line 118 of file DipoleAlgorithms.h.

NEG_FLAG

meas::base::FlagDefinition const lsst::ip::diffim::DipoleFluxAlgorithm::NEG_FLAG = dipoleFluxFlagDefinitions.add("neg_flag", "failure flag for negative, set if anything went wrong")

staticinherited

Definition at line 120 of file DipoleAlgorithms.h.

POS_FLAG

meas::base::FlagDefinition const lsst::ip::diffim::DipoleFluxAlgorithm::POS_FLAG = dipoleFluxFlagDefinitions.add("pos_flag", "failure flag for positive, set if anything went wrong")

staticinherited

Definition at line 119 of file DipoleAlgorithms.h.

---

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/ip_diffim/g180d380827+7a4e862ed4/include/lsst/ip/diffim/DipoleAlgorithms.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/ip_diffim/g180d380827+7a4e862ed4/src/DipoleAlgorithms.cc