lsst::jointcal::ConstrainedMagnitudeModel Class Reference

#include <ConstrainedPhotometryModel.h>

Inheritance diagram for lsst::jointcal::ConstrainedMagnitudeModel:

Public Member Functions
	ConstrainedMagnitudeModel (CcdImageList const &ccdImageList, geom::Box2D const &focalPlaneBBox, int visitOrder=7, double errorPedestal=0)
void	offsetFittedStar (FittedStar &fittedStar, double delta) const override
	Offset the appropriate flux or magnitude (by -delta).
double	computeResidual (CcdImage const &ccdImage, MeasuredStar const &measuredStar) const override
	Compute the residual between the model applied to a star and its associated fittedStar.
double	computeRefResidual (FittedStar const &fittedStar, RefStar const &refStar) const override
	Return the fittedStar - refStar residual appropriate for this model (e.g. flux - flux or mag - mag).
double	getRefError (RefStar const &refStar) const override
	Return the refStar error appropriate for this model (e.g. fluxErr or magErr).
double	transform (CcdImage const &ccdImage, MeasuredStar const &measuredStar) const override
	Return the on-sky transformed flux for measuredStar on ccdImage.
double	transformError (CcdImage const &ccdImage, MeasuredStar const &measuredStar) const override
	Return the on-sky transformed flux uncertainty for measuredStar on ccdImage.
std::shared_ptr< afw::image::PhotoCalib >	toPhotoCalib (CcdImage const &ccdImage) const override
	Return the mapping of ccdImage represented as a PhotoCalib.
void	print (std::ostream &out) const override
	Print a string representation of the contents of this mapping, for debugging.
Eigen::Index	assignIndices (std::string const &whatToFit, Eigen::Index firstIndex) override
	Assign indices in the full matrix to the parameters being fit in the mappings, starting at firstIndex.
void	offsetParams (Eigen::VectorXd const &delta) override
	Offset the parameters by the provided amounts (by -delta).
void	freezeErrorTransform () override
	Once this routine has been called, the error transform is not modified by offsetParams().
void	getMappingIndices (CcdImage const &ccdImage, IndexVector &indices) const override
	Get how this set of parameters (of length Npar()) map into the "grand" fit.
std::size_t	getTotalParameters () const override
	Return the total number of parameters in this model.
void	computeParameterDerivatives (MeasuredStar const &measuredStar, CcdImage const &ccdImage, Eigen::VectorXd &derivatives) const override
	Compute the parametric derivatives of this model.
std::size_t	getNpar (CcdImage const &ccdImage) const
	Return the number of parameters in the mapping of CcdImage.
PhotometryMappingBase const &	getMapping (CcdImage const &ccdImage) const
	Get the mapping associated with ccdImage.
bool	validate (CcdImageList const &ccdImageList, int ndof) const
	Return true if this is a "reasonable" model.
bool	checkPositiveOnBBox (CcdImage const &ccdImage) const
	Check that the model is positive on the ccdImage bbox.
double	getErrorPedestal () const
double	tweakFluxError (jointcal::MeasuredStar const &measuredStar) const
	Add a fraction of the instrumental flux to the instrumental flux error, in quadrature.
double	tweakMagnitudeError (jointcal::MeasuredStar const &measuredStar) const
	Add a small magnitude offset to the "instrumental magnitude" error, in quadrature.

Protected Types
using	MapType = std::unordered_map<CcdImageKey, std::unique_ptr<ChipVisitPhotometryMapping>>
using	VisitMapType = std::map<VisitIdType, std::shared_ptr<PhotometryMapping>>
using	ChipMapType = std::map<CcdIdType, std::shared_ptr<PhotometryMapping>>

Protected Member Functions
double	initialChipCalibration (std::shared_ptr< afw::image::PhotoCalib const > photoCalib) override
	Return the initial calibration to use from this photoCalib.
PhotometryMappingBase *	findMapping (CcdImage const &ccdImage) const override
	Return a pointer to the mapping associated with this ccdImage.
template<class ChipTransform , class VisitTransform , class ChipVisitMapping >
void	initialize (CcdImageList const &ccdImageList, geom::Box2D const &focalPlaneBBox, int visitOrder)
	Initialize the chip, visit, and chipVisit mappings by creating appropriate transforms and mappings.
PrepPhotoCalib	prepPhotoCalib (CcdImage const &ccdImage) const
	Helper for preparing toPhotoCalib()

Protected Attributes
MapType	_chipVisitMap
VisitMapType	_visitMap
ChipMapType	_chipMap
LOG_LOGGER	_log
	lsst.logging instance, to be created by a subclass so that messages have consistent name.
double	errorPedestal

Detailed Description

Definition at line 186 of file ConstrainedPhotometryModel.h.

Member Typedef Documentation

ChipMapType

using lsst::jointcal::ConstrainedPhotometryModel::ChipMapType = std::map<CcdIdType, std::shared_ptr<PhotometryMapping>>

protectedinherited

Definition at line 111 of file ConstrainedPhotometryModel.h.

MapType

using lsst::jointcal::ConstrainedPhotometryModel::MapType = std::unordered_map<CcdImageKey, std::unique_ptr<ChipVisitPhotometryMapping>>

protectedinherited

Definition at line 104 of file ConstrainedPhotometryModel.h.

VisitMapType

using lsst::jointcal::ConstrainedPhotometryModel::VisitMapType = std::map<VisitIdType, std::shared_ptr<PhotometryMapping>>

protectedinherited

Definition at line 108 of file ConstrainedPhotometryModel.h.

Constructor & Destructor Documentation

ConstrainedMagnitudeModel()

lsst::jointcal::ConstrainedMagnitudeModel::ConstrainedMagnitudeModel ( CcdImageList const & ccdImageList, geom::Box2D const & focalPlaneBBox, int visitOrder = 7, double errorPedestal = 0 )

inlineexplicit

Definition at line 188 of file ConstrainedPhotometryModel.h.

            : ConstrainedPhotometryModel(ccdImageList, focalPlaneBBox,
                                         LOG_GET("lsst.jointcal.ConstrainedMagnitudeModel"), visitOrder,
                                         errorPedestal) {
        initialize<MagnitudeTransformSpatiallyInvariant, MagnitudeTransformChebyshev,
                   ChipVisitMagnitudeMapping>(ccdImageList, focalPlaneBBox, visitOrder);
    }

Member Function Documentation

assignIndices()

Eigen::Index lsst::jointcal::ConstrainedPhotometryModel::assignIndices ( std::string const & whatToFit, Eigen::Index firstIndex )

overridevirtualinherited

Assign indices in the full matrix to the parameters being fit in the mappings, starting at firstIndex.

Parameters

[in]	whatToFit	String containing parameters to fit.
[in]	firstIndex	Index to start assigning at.

Returns

The highest assigned index.

Implements lsst::jointcal::PhotometryModel.

Definition at line 45 of file ConstrainedPhotometryModel.cc.

                                                                              {
    Eigen::Index index = firstIndex;
    if (whatToFit.find("Model") == std::string::npos) {
        LOGLS_WARN(_log, "assignIndices was called and Model is *not* in whatToFit");
        return index;
    }
 
    // If we got here, "Model" is definitely in whatToFit.
    _fittingChips = (whatToFit.find("ModelChip") != std::string::npos);
    _fittingVisits = (whatToFit.find("ModelVisit") != std::string::npos);
    // If nothing more than "Model" is specified, it means fit everything.
    if ((!_fittingChips) && (!_fittingVisits)) {
        _fittingChips = _fittingVisits = true;
    }
 
    if (_fittingChips) {
        for (auto &idMapping : _chipMap) {
            auto mapping = idMapping.second.get();
            // Don't assign indices for fixed parameters.
            if (mapping->isFixed()) continue;
            mapping->setIndex(index);
            index += mapping->getNpar();
        }
    }
    if (_fittingVisits) {
        for (auto &idMapping : _visitMap) {
            auto mapping = idMapping.second.get();
            mapping->setIndex(index);
            index += mapping->getNpar();
        }
    }
    for (auto &idMapping : _chipVisitMap) {
        idMapping.second->setWhatToFit(_fittingChips, _fittingVisits);
    }
    return index;
}

checkPositiveOnBBox()

bool lsst::jointcal::PhotometryModel::checkPositiveOnBBox ( CcdImage const & ccdImage ) const

inherited

Check that the model is positive on the ccdImage bbox.

Parameters

ccdImage

The ccdImage to test.

Returns

True if the image is positive on a sampling of points of the ccdImage bbox.

Definition at line 49 of file PhotometryModel.cc.

                                                                        {
    bool check = true;
    auto bbox = ccdImage.getImageFrame();
    for (auto const &x : {bbox.xMin, bbox.getCenter().x, bbox.xMax})
        for (auto const &y : {bbox.yMin, bbox.getCenter().y, bbox.yMax}) {
            // flux, fluxErr, instFlux, instFluxErr all 1
            jointcal::MeasuredStar star(jointcal::BaseStar(x, y, 1, 1));
            star.setInstFluxAndErr(1, 1);
            double result = transform(ccdImage, star);
            // Don't short circuit so that we log every place the model is negative.
            if (result < 0) {
                LOGLS_WARN(_log, "CcdImage " << ccdImage.getName() << " is negative at (" << x << "," << y
                                             << "): " << result);
                check = false;
            }
        }
    return check;
}

computeParameterDerivatives()

void lsst::jointcal::ConstrainedPhotometryModel::computeParameterDerivatives ( MeasuredStar const & measuredStar, CcdImage const & ccdImage, Eigen::VectorXd & derivatives ) const

overridevirtualinherited

Compute the parametric derivatives of this model.

Parameters

[in]	measuredStar	The measured star with the position and flux to compute at.
[in]	ccdImage	The ccdImage containing the measured star, to find the correct mapping.
[out]	derivatives	The computed derivatives. Must be pre-allocated to the correct size.

Implements lsst::jointcal::PhotometryModel.

Definition at line 125 of file ConstrainedPhotometryModel.cc.

                                                                                               {
    auto mapping = findMapping(ccdImage);
    mapping->computeParameterDerivatives(measuredStar, measuredStar.getInstFlux(), derivatives);
}

computeRefResidual()

double lsst::jointcal::ConstrainedMagnitudeModel::computeRefResidual ( FittedStar const & fittedStar, RefStar const & refStar ) const

inlineoverridevirtual

Return the fittedStar - refStar residual appropriate for this model (e.g. flux - flux or mag - mag).

Implements lsst::jointcal::PhotometryModel.

Definition at line 206 of file ConstrainedPhotometryModel.h.

                                                                                                   {
        return fittedStar.getMag() - refStar.getMag();
    };

computeResidual()

double lsst::jointcal::ConstrainedMagnitudeModel::computeResidual ( CcdImage const & ccdImage, MeasuredStar const & measuredStar ) const

overridevirtual

Compute the residual between the model applied to a star and its associated fittedStar.

\[ residual = Model(measuredStar) - fittedStar \]

Parameters

ccdImage	The ccdImage where measuredStar resides.
measuredStar	The measured star position to compute the residual of.

Returns

The residual.

Implements lsst::jointcal::PhotometryModel.

Definition at line 310 of file ConstrainedPhotometryModel.cc.

                                                                                          {
    return transform(ccdImage, measuredStar) - measuredStar.getFittedStar()->getMag();
}

findMapping()

PhotometryMappingBase * lsst::jointcal::ConstrainedPhotometryModel::findMapping ( CcdImage const & ccdImage ) const

overrideprotectedvirtualinherited

Return a pointer to the mapping associated with this ccdImage.

Implements lsst::jointcal::PhotometryModel.

Definition at line 168 of file ConstrainedPhotometryModel.cc.

                                                                                             {
    auto idMapping = _chipVisitMap.find(ccdImage.getHashKey());
    if (idMapping == _chipVisitMap.end())
        throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
                          "ConstrainedPhotometryModel cannot find CcdImage " + ccdImage.getName());
    return idMapping->second.get();
}

freezeErrorTransform()

void lsst::jointcal::ConstrainedPhotometryModel::freezeErrorTransform ( )

overridevirtualinherited

Once this routine has been called, the error transform is not modified by offsetParams().

The routine can be called when the mappings are roughly in place. After the call, the transformations used to propagate errors are no longer affected when updating the mappings. This allows an exactly linear fit, which can be necessary for some model+data combinations.

Implements lsst::jointcal::PhotometryModel.

Definition at line 100 of file ConstrainedPhotometryModel.cc.

                                                      {
    for (auto &idMapping : _chipMap) {
        idMapping.second->freezeErrorTransform();
    }
    for (auto &idMapping : _visitMap) {
        idMapping.second->freezeErrorTransform();
    }
}

getErrorPedestal()

double lsst::jointcal::PhotometryModel::getErrorPedestal ( ) const

inlineinherited

Definition at line 197 of file PhotometryModel.h.

{ return errorPedestal; }

getMapping()

PhotometryMappingBase const & lsst::jointcal::PhotometryModel::getMapping ( CcdImage const & ccdImage ) const

inlineinherited

Get the mapping associated with ccdImage.

Definition at line 157 of file PhotometryModel.h.

                                                                            {
        return *(findMapping(ccdImage));
    }

getMappingIndices()

void lsst::jointcal::ConstrainedPhotometryModel::getMappingIndices ( CcdImage const & ccdImage, IndexVector & indices ) const

overridevirtualinherited

Get how this set of parameters (of length Npar()) map into the "grand" fit.

Parameters

[in]	ccdImage	The ccdImage to look up.
[out]	indices	The indices of the mapping associated with ccdImage.

Implements lsst::jointcal::PhotometryModel.

Definition at line 109 of file ConstrainedPhotometryModel.cc.

                                                                                                       {
    auto mapping = findMapping(ccdImage);
    mapping->getMappingIndices(indices);
}

getNpar()

std::size_t lsst::jointcal::PhotometryModel::getNpar ( CcdImage const & ccdImage ) const

inlineinherited

Return the number of parameters in the mapping of CcdImage.

Definition at line 154 of file PhotometryModel.h.

{ return findMapping(ccdImage)->getNpar(); }

getRefError()

double lsst::jointcal::ConstrainedMagnitudeModel::getRefError ( RefStar const & refStar ) const

inlineoverridevirtual

Return the refStar error appropriate for this model (e.g. fluxErr or magErr).

Implements lsst::jointcal::PhotometryModel.

Definition at line 211 of file ConstrainedPhotometryModel.h.

{ return refStar.getMagErr(); }

getTotalParameters()

std::size_t lsst::jointcal::ConstrainedPhotometryModel::getTotalParameters ( ) const

overridevirtualinherited

Return the total number of parameters in this model.

Implements lsst::jointcal::PhotometryModel.

Definition at line 114 of file ConstrainedPhotometryModel.cc.

                                                               {
    std::size_t total = 0;
    for (auto &idMapping : _chipMap) {
        total += idMapping.second->getNpar();
    }
    for (auto &idMapping : _visitMap) {
        total += idMapping.second->getNpar();
    }
    return total;
}

initialChipCalibration()

double lsst::jointcal::ConstrainedMagnitudeModel::initialChipCalibration ( std::shared_ptr< afw::image::PhotoCalib const > photoCalib )

inlineoverrideprotectedvirtual

Return the initial calibration to use from this photoCalib.

Implements lsst::jointcal::ConstrainedPhotometryModel.

Definition at line 227 of file ConstrainedPhotometryModel.h.

                                                                                               {
        return cpputils::nanojanskyToABMagnitude(photoCalib->getCalibrationMean());
    }

initialize()

template<class ChipTransform , class VisitTransform , class ChipVisitMapping >

template void lsst::jointcal::ConstrainedPhotometryModel::initialize< MagnitudeTransformSpatiallyInvariant, MagnitudeTransformChebyshev, ChipVisitMagnitudeMapping > ( CcdImageList const & ccdImageList, geom::Box2D const & focalPlaneBBox, int visitOrder )

protectedinherited

Initialize the chip, visit, and chipVisit mappings by creating appropriate transforms and mappings.

Definition at line 177 of file ConstrainedPhotometryModel.cc.

                                                                                             {
    // keep track of which chip we want to constrain (the one closest to the middle of the focal plane)
    double minRadius2 = std::numeric_limits<double>::infinity();
    CcdIdType constrainedChip = -1;
 
    // First initialize all visit and ccd transforms, before we make the ccdImage mappings.
    for (auto const &ccdImage : ccdImageList) {
        auto visit = ccdImage->getVisit();
        auto chip = ccdImage->getCcdId();
        auto visitPair = _visitMap.find(visit);
        auto chipPair = _chipMap.find(chip);
 
        // If the chip is not in the map, add it, otherwise continue.
        if (chipPair == _chipMap.end()) {
            auto center = ccdImage->getDetector()->getCenter(afw::cameraGeom::FOCAL_PLANE);
            double radius2 = std::pow(center.getX(), 2) + std::pow(center.getY(), 2);
            if (radius2 < minRadius2) {
                minRadius2 = radius2;
                constrainedChip = chip;
            }
            auto photoCalib = ccdImage->getPhotoCalib();
            // Use the single-frame processing calibration from the PhotoCalib as the default.
            auto chipTransform = std::make_unique<ChipTransform>(initialChipCalibration(photoCalib));
            _chipMap[chip] = std::make_shared<PhotometryMapping>(std::move(chipTransform));
        }
        // If the visit is not in the map, add it, otherwise continue.
        if (visitPair == _visitMap.end()) {
            auto visitTransform = std::make_unique<VisitTransform>(visitOrder, focalPlaneBBox);
            _visitMap[visit] = std::make_shared<PhotometryMapping>(std::move(visitTransform));
        }
    }
 
    // Fix one chip mapping, to remove the degeneracy from the system.
    _chipMap.at(constrainedChip)->setFixed(true);
 
    // Now create the ccdImage mappings, which are combinations of the chip/visit mappings above.
    for (auto const &ccdImage : ccdImageList) {
        auto visit = ccdImage->getVisit();
        auto chip = ccdImage->getCcdId();
        _chipVisitMap.emplace(ccdImage->getHashKey(),
                              std::make_unique<ChipVisitMapping>(_chipMap[chip], _visitMap[visit]));
    }
    LOGLS_INFO(_log, "Got " << _chipMap.size() << " chip mappings and " << _visitMap.size()
                            << " visit mappings; holding chip " << constrainedChip << " fixed ("
                            << getTotalParameters() << " total parameters).");
    LOGLS_DEBUG(_log, "CcdImage map has " << _chipVisitMap.size() << " mappings, with "
                                          << _chipVisitMap.bucket_count() << " buckets and a load factor of "
                                          << _chipVisitMap.load_factor());
}

offsetFittedStar()

void lsst::jointcal::ConstrainedMagnitudeModel::offsetFittedStar ( FittedStar & fittedStar, double delta ) const

inlineoverridevirtual

Offset the appropriate flux or magnitude (by -delta).

Parameters

fittedStar	The star to update.
delta	The amount to update by.

Implements lsst::jointcal::PhotometryModel.

Definition at line 198 of file ConstrainedPhotometryModel.h.

                                                                               {
        fittedStar.getMag() -= delta;
    }

offsetParams()

void lsst::jointcal::ConstrainedPhotometryModel::offsetParams ( Eigen::VectorXd const & delta )

overridevirtualinherited

Offset the parameters by the provided amounts (by -delta).

The shifts are applied according to the indices given in assignIndices.

Parameters

[in]

delta

vector of offsets to apply

Implements lsst::jointcal::PhotometryModel.

Definition at line 83 of file ConstrainedPhotometryModel.cc.

                                                                        {
    if (_fittingChips) {
        for (auto &idMapping : _chipMap) {
            auto mapping = idMapping.second.get();
            // Don't offset indices for fixed parameters.
            if (mapping->isFixed()) continue;
            mapping->offsetParams(delta.segment(mapping->getIndex(), mapping->getNpar()));
        }
    }
    if (_fittingVisits) {
        for (auto &idMapping : _visitMap) {
            auto mapping = idMapping.second.get();
            mapping->offsetParams(delta.segment(mapping->getIndex(), mapping->getNpar()));
        }
    }
}

prepPhotoCalib()

ConstrainedPhotometryModel::PrepPhotoCalib lsst::jointcal::ConstrainedPhotometryModel::prepPhotoCalib ( CcdImage const & ccdImage ) const

protectedinherited

Helper for preparing toPhotoCalib()

Definition at line 228 of file ConstrainedPhotometryModel.cc.

                                        {
    auto detector = ccdImage.getDetector();
    auto ccdBBox = detector->getBBox();
    auto *mapping = dynamic_cast<ChipVisitPhotometryMapping *>(findMapping(ccdImage));
 
    // There should be no way in which we can get to this point and not have a ChipVisitMapping,
    // so blow up if we don't.
    assert(mapping != nullptr);
    // We know it's a Chebyshev transform because we created it as such, so blow up if it's not.
    auto visitPhotometryTransform = std::dynamic_pointer_cast<PhotometryTransformChebyshev>(
            mapping->getVisitMapping()->getTransform());
    assert(visitPhotometryTransform != nullptr);
    auto focalBBox = visitPhotometryTransform->getBBox();
 
    // Unravel our chebyshev coefficients to build an astshim::ChebyMap.
    auto coeff_f = toChebyMapCoeffs(std::dynamic_pointer_cast<PhotometryTransformChebyshev>(
            mapping->getVisitMapping()->getTransform()));
    // Bounds are the bbox
    std::vector<double> lowerBound = {focalBBox.getMinX(), focalBBox.getMinY()};
    std::vector<double> upperBound = {focalBBox.getMaxX(), focalBBox.getMaxY()};
    afw::geom::TransformPoint2ToGeneric visitTransform(ast::ChebyMap(coeff_f, 1, lowerBound, upperBound));
 
    double chipConstant = mapping->getChipMapping()->getParameters()[0];
 
    // Compute a box that covers the area of the ccd in focal plane coordinates.
    // This is the box over which we want to compute the mean of the visit transform.
    auto pixToFocal = detector->getTransform(afw::cameraGeom::PIXELS, afw::cameraGeom::FOCAL_PLANE);
    geom::Box2D ccdBBoxInFocal;
    for (auto const &point : pixToFocal->applyForward(geom::Box2D(ccdBBox).getCorners())) {
        ccdBBoxInFocal.include(point);
    }
    double visitMean = visitPhotometryTransform->mean(ccdBBoxInFocal);
 
    return {chipConstant, visitTransform, pixToFocal, visitMean};
}

print()

void lsst::jointcal::ConstrainedMagnitudeModel::print ( std::ostream & out ) const

overridevirtual

Print a string representation of the contents of this mapping, for debugging.

This string representation can be very verbose, as it contains all of the parameters of all of the transforms in this model.

Implements lsst::jointcal::PhotometryModel.

Definition at line 353 of file ConstrainedPhotometryModel.cc.

                                                           {
    out << "ConstrainedMagnitudeModel (" << _chipVisitMap.size() << " composite mappings; " << _chipMap.size()
        << " sensor mappings, " << _visitMap.size() << " visit mappings):" << std::endl;
    ConstrainedPhotometryModel::print(out);
}

toPhotoCalib()

std::shared_ptr< afw::image::PhotoCalib > lsst::jointcal::ConstrainedMagnitudeModel::toPhotoCalib ( CcdImage const & ccdImage ) const

overridevirtual

Return the mapping of ccdImage represented as a PhotoCalib.

Implements lsst::jointcal::PhotometryModel.

Definition at line 328 of file ConstrainedPhotometryModel.cc.

                                        {
    auto ccdBBox = ccdImage.getDetector()->getBBox();
    auto prep = prepPhotoCalib(ccdImage);
 
    using namespace std::string_literals;  // for operator""s to convert string literal->std::string
    afw::geom::Transform<afw::geom::GenericEndpoint, afw::geom::GenericEndpoint> logTransform(
            ast::MathMap(1, 1, {"y=pow(10.0,x/-2.5)"s}, {"x=-2.5*log10(y)"s}));
 
    // The chip part is easy: zoom map with the value (converted to a flux) as the "zoom" factor.
    double chipCalibration = cpputils::ABMagnitudeToNanojansky(prep.chipConstant);
    afw::geom::Transform<afw::geom::GenericEndpoint, afw::geom::GenericEndpoint> zoomTransform(
            ast::ZoomMap(1, chipCalibration));
 
    // Now stitch them all together.
    auto transform = prep.pixToFocal->then(prep.visitTransform)->then(logTransform)->then(zoomTransform);
 
    // NOTE: TransformBoundedField does not implement mean(), so we have to compute it here.
    double mean = chipCalibration * std::pow(10, prep.visitMean / -2.5);
 
    auto boundedField = std::make_shared<afw::math::TransformBoundedField>(ccdBBox, *transform);
    return std::make_shared<afw::image::PhotoCalib>(mean, ccdImage.getPhotoCalib()->getCalibrationErr(),
                                                    boundedField, false);
}

transform()

double lsst::jointcal::ConstrainedMagnitudeModel::transform ( CcdImage const & ccdImage, MeasuredStar const & measuredStar ) const

overridevirtual

Return the on-sky transformed flux for measuredStar on ccdImage.

Parameters

[in]	ccdImage	The ccdImage where measuredStar resides.
	measuredStar	The measured star position to transform.

Returns

The on-sky flux transformed from instFlux at measuredStar's position.

Implements lsst::jointcal::PhotometryModel.

Definition at line 315 of file ConstrainedPhotometryModel.cc.

                                                                                    {
    auto mapping = findMapping(ccdImage);
    return mapping->transform(measuredStar, measuredStar.getInstMag());
}

transformError()

double lsst::jointcal::ConstrainedMagnitudeModel::transformError ( CcdImage const & ccdImage, MeasuredStar const & measuredStar ) const

overridevirtual

Return the on-sky transformed flux uncertainty for measuredStar on ccdImage.

Identical to transform() until freezeErrorTransform() is called.

Parameters

[in]	ccdImage	The ccdImage where measuredStar resides.
	measuredStar	The measured star position to transform.

Returns

The on-sky flux transformed from instFlux at measuredStar's position.

Implements lsst::jointcal::PhotometryModel.

Definition at line 321 of file ConstrainedPhotometryModel.cc.

                                                                                         {
    auto mapping = findMapping(ccdImage);
    double tempErr = tweakFluxError(measuredStar);
    return mapping->transformError(measuredStar, measuredStar.getInstFlux(), tempErr);
}

tweakFluxError()

double lsst::jointcal::PhotometryModel::tweakFluxError ( jointcal::MeasuredStar const & measuredStar ) const

inlineinherited

Add a fraction of the instrumental flux to the instrumental flux error, in quadrature.

Definition at line 200 of file PhotometryModel.h.

                                                                          {
        if (errorPedestal == 0) {
            return measuredStar.getInstFluxErr();
        } else {
            return std::hypot(measuredStar.getInstFluxErr(), measuredStar.getInstFlux() * errorPedestal);
        }
    }

tweakMagnitudeError()

double lsst::jointcal::PhotometryModel::tweakMagnitudeError ( jointcal::MeasuredStar const & measuredStar ) const

inlineinherited

Add a small magnitude offset to the "instrumental magnitude" error, in quadrature.

Definition at line 209 of file PhotometryModel.h.

                                                                               {
        if (errorPedestal == 0) {
            return measuredStar.getInstMagErr();
        } else {
            return std::hypot(measuredStar.getInstMagErr(), errorPedestal);
        }
    }

validate()

bool lsst::jointcal::PhotometryModel::validate ( CcdImageList const & ccdImageList, int ndof ) const

inherited

Return true if this is a "reasonable" model.

A valid photometry model is positive within each sensor's bounding box.

Parameters

ccdImageList	The ccdImages to test the model validity on.
ndof	The number of degrees of freedom in the fit, e.g. from Fitterbase.computeChi2().

Returns

True if the model is valid on all ccdImages.

Definition at line 33 of file PhotometryModel.cc.

                                                                               {
    bool check = true;
    for (auto const &ccdImage : ccdImageList) {
        // Don't short circuit so that we log every place the model is negative.
        check &= checkPositiveOnBBox(*ccdImage);
    }
    if (ndof < 0) {
        check &= false;
        LOGLS_ERROR(_log, "This model only has "
                                  << ndof << " degrees of freedom, with " << getTotalParameters()
                                  << " total parameters. Reduce the model complexity (e.g. polynomial order)"
                                     " to better match the number of measured sources.");
    }
    return check;
}

Member Data Documentation

_chipMap

ChipMapType lsst::jointcal::ConstrainedPhotometryModel::_chipMap

protectedinherited

Definition at line 112 of file ConstrainedPhotometryModel.h.

_chipVisitMap

MapType lsst::jointcal::ConstrainedPhotometryModel::_chipVisitMap

protectedinherited

Definition at line 105 of file ConstrainedPhotometryModel.h.

_log

LOG_LOGGER lsst::jointcal::PhotometryModel::_log

protectedinherited

lsst.logging instance, to be created by a subclass so that messages have consistent name.

Definition at line 224 of file PhotometryModel.h.

_visitMap

VisitMapType lsst::jointcal::ConstrainedPhotometryModel::_visitMap

protectedinherited

Definition at line 109 of file ConstrainedPhotometryModel.h.

errorPedestal

double lsst::jointcal::PhotometryModel::errorPedestal

protectedinherited

Definition at line 227 of file PhotometryModel.h.

---

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/jointcal/g82479be7b0+ed77629bff/include/lsst/jointcal/ConstrainedPhotometryModel.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/jointcal/g82479be7b0+ed77629bff/src/ConstrainedPhotometryModel.cc