lsst::jointcal::SimplePolyModel Class Reference

this is the model used to fit independent CCDs, meaning that there is no instrument model. More...

#include <SimplePolyModel.h>

Inheritance diagram for lsst::jointcal::SimplePolyModel:

Public Member Functions
	SimplePolyModel (CcdImageList const &ccdImageList, ProjectionHandler const *projectionHandler, bool initFromWCS, unsigned nNotFit=0, unsigned degree=3)
	Sky2TP is just a name, it can be anything. More...
	SimplePolyModel (SimplePolyModel const &)=delete
	No copy or move: there is only ever one instance of a given model (i.e.. per ccd+visit) More...
	SimplePolyModel (SimplePolyModel &&)=delete
SimplePolyModel &	operator= (SimplePolyModel const &)=delete
SimplePolyModel &	operator= (SimplePolyModel &&)=delete
const Mapping *	getMapping (CcdImage const &) const
	Mapping associated to a given CcdImage. More...
unsigned	assignIndices (unsigned firstIndex, std::string const &whatToFit)
	Positions the various parameter sets into the parameter vector, starting at firstIndex. More...
void	offsetParams (Eigen::VectorXd const &delta)
	Offset the parameters by the provided amounts. More...
const Gtransfo *	getSky2TP (CcdImage const &ccdImage) const
	the mapping of sky coordinates (i.e. More...
virtual void	freezeErrorTransform ()
Gtransfo const &	getTransfo (CcdImage const &ccdImage) const
	Access to mappings. More...
std::shared_ptr< TanSipPix2RaDec >	produceSipWcs (CcdImage const &ccdImage) const
	Cook up a SIP WCS. More...
	~SimplePolyModel ()

Detailed Description

this is the model used to fit independent CCDs, meaning that there is no instrument model.

Definition at line 29 of file SimplePolyModel.h.

Constructor & Destructor Documentation

SimplePolyModel() [1/3]

lsst::jointcal::SimplePolyModel::SimplePolyModel	(	CcdImageList const &	ccdImageList,
		ProjectionHandler const *	projectionHandler,
		bool	initFromWCS,
		unsigned	nNotFit = 0,
		unsigned	degree = 3
	)

Sky2TP is just a name, it can be anything.

Definition at line 22 of file SimplePolyModel.cc.

        : _sky2TP(projectionHandler)

{
    // from datacards (or default)
    //  unsigned degree = distortionDegree;
    unsigned count = 0;

    for (auto i = ccdImageList.cbegin(); i != ccdImageList.cend(); ++i, ++count) {
        const CcdImage &im = **i;
        if (count < nNotFit) {
            std::unique_ptr<SimpleGtransfoMapping> id(new SimpleGtransfoMapping(GtransfoIdentity()));
            id->setIndex(-1);  // non sense, because it has no parameters
            _myMap[&im] = std::move(id);
        } else
        // Given how AssignIndices works, only the SimplePolyMapping's
        // will actually be fitted, as nNotFit requests.
        {
            /* first check that there are enough measurements for the
      requested polynomial degree */
            size_t nObj = im.getCatalogForFit().size();
            if (nObj == 0) {
                LOGLS_WARN(_log, "Empty catalog from image: " << im.getName());
                continue;
            }
            GtransfoPoly pol(degree);
            if (pol.getDegree() > 0)  // if not, it cannot be decreased
                while (unsigned(pol.getNpar()) > 2 * nObj) pol.setDegree(pol.getDegree() - 1);
            /* We have to center and normalize the coordinates so that
               the fit matrix is not too ill-conditionned. Basically, x
               and y in pixels are mapped to [-1,1]. When the
               transformation of SimplePolyMapping transformation is
               accessed, the combination of the normalization and the
               fitted transformation is returned, so that the trick
               remains hidden
             */
            const Frame &frame = im.getImageFrame();
            GtransfoLin shiftAndNormalize = normalizeCoordinatesTransfo(frame);
            if (initFromWcs) {
                pol = GtransfoPoly(im.getPix2TangentPlane(), frame, degree);
                pol = pol * shiftAndNormalize.invert();
            }
            _myMap[&im] =
                    std::unique_ptr<SimpleGtransfoMapping>(new SimplePolyMapping(shiftAndNormalize, pol));
        }
    }
}

SimplePolyModel() [2/3]

lsst::jointcal::SimplePolyModel::SimplePolyModel ( SimplePolyModel const &  )

delete

No copy or move: there is only ever one instance of a given model (i.e.. per ccd+visit)

SimplePolyModel() [3/3]

lsst::jointcal::SimplePolyModel::SimplePolyModel ( SimplePolyModel &&  )

delete

~SimplePolyModel()

lsst::jointcal::SimplePolyModel::~SimplePolyModel ( )

inline

Definition at line 64 of file SimplePolyModel.h.

{};

Member Function Documentation

assignIndices()

unsigned lsst::jointcal::SimplePolyModel::assignIndices ( unsigned  firstIndex, std::string const &  whatToFit  )

virtual

Positions the various parameter sets into the parameter vector, starting at firstIndex.

Implements lsst::jointcal::AstrometryModel.

Definition at line 79 of file SimplePolyModel.cc.

                                                                                       {
    if (whatToFit.find("Distortions") == std::string::npos) {
        LOGLS_ERROR(_log, "AssignIndices was called and Distortions is *not* in whatToFit.");
        return 0;
    }
    unsigned index = firstIndex;
    for (auto i = _myMap.begin(); i != _myMap.end(); ++i) {
        SimplePolyMapping *p = dynamic_cast<SimplePolyMapping *>(&*(i->second));
        if (!p) continue;  // it should be GtransfoIdentity
        p->setIndex(index);
        index += p->getNpar();
    }
    return index;
}

freezeErrorTransform()

void lsst::jointcal::SimplePolyModel::freezeErrorTransform ( )

virtual

Implements lsst::jointcal::AstrometryModel.

Definition at line 101 of file SimplePolyModel.cc.

                                           {
    for (auto i = _myMap.begin(); i != _myMap.end(); ++i) i->second->freezeErrorTransform();
}

getMapping()

const Mapping * lsst::jointcal::SimplePolyModel::getMapping ( CcdImage const &  ) const

virtual

Mapping associated to a given CcdImage.

Implements lsst::jointcal::AstrometryModel.

Definition at line 71 of file SimplePolyModel.cc.

                                                                         {
    mapType::const_iterator i = _myMap.find(&ccdImage);
    if (i == _myMap.cend())
        throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
                          "SimplePolyModel::GetMapping, never heard of CcdImage " + ccdImage.getName());
    return (i->second.get());
}

getSky2TP()

const Gtransfo* lsst::jointcal::SimplePolyModel::getSky2TP ( CcdImage const &  ccdImage ) const

inlinevirtual

the mapping of sky coordinates (i.e.

the coordinate system in which fitted stars are reported) onto the Tangent plane (into which the pixel coordinates are transformed)

Implements lsst::jointcal::AstrometryModel.

Definition at line 54 of file SimplePolyModel.h.

{ return _sky2TP->getSky2TP(ccdImage); }

getTransfo()

const Gtransfo & lsst::jointcal::SimplePolyModel::getTransfo

(

CcdImage const &

ccdImage

)

const

Access to mappings.

Definition at line 105 of file SimplePolyModel.cc.

                                                                          {
    // return GetMapping(ccdImage)->Transfo(); // cannot do that
    auto p = _myMap.find(&ccdImage);
    if (p == _myMap.end())
        throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
                          "SimplePolyModel::getTransfo, never heard of CcdImage " + ccdImage.getName());
    return p->second->getTransfo();
}

offsetParams()

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

virtual

Offset the parameters by the provided amounts.

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

Implements lsst::jointcal::AstrometryModel.

Definition at line 94 of file SimplePolyModel.cc.

                                                             {
    for (auto &i : _myMap) {
        auto mapping = i.second.get();
        mapping->offsetParams(delta.segment(mapping->getIndex(), mapping->getNpar()));
    }
}

operator=() [1/2]

SimplePolyModel& lsst::jointcal::SimplePolyModel::operator= ( SimplePolyModel const &  )

delete

operator=() [2/2]

SimplePolyModel& lsst::jointcal::SimplePolyModel::operator= ( SimplePolyModel &&  )

delete

produceSipWcs()

std::shared_ptr< TanSipPix2RaDec > lsst::jointcal::SimplePolyModel::produceSipWcs ( CcdImage const &  ccdImage ) const

virtual

Cook up a SIP WCS.

Implements lsst::jointcal::AstrometryModel.

Definition at line 114 of file SimplePolyModel.cc.

                                                                                            {
    const GtransfoPoly &pix2Tp = dynamic_cast<const GtransfoPoly &>(getTransfo(ccdImage));
    const TanRaDec2Pix *proj = dynamic_cast<const TanRaDec2Pix *>(getSky2TP(ccdImage));
    if (!proj) return nullptr;

    const GtransfoLin &projLinPart = proj->getLinPart();  // should be the identity, but who knows? So, let us
                                                          // incorporate it into the pix2TP part.
    GtransfoPoly wcsPix2Tp = GtransfoPoly(projLinPart.invert()) * pix2Tp;

    // compute a decent approximation, if higher order corrections get ignored
    GtransfoLin cdStuff = wcsPix2Tp.linearApproximation(ccdImage.getImageFrame().getCenter());

    // wcsPix2TP = cdStuff*sip , so
    GtransfoPoly sip = GtransfoPoly(cdStuff.invert()) * wcsPix2Tp;
    Point tangentPoint(proj->getTangentPoint());
    return std::make_shared<TanSipPix2RaDec>(cdStuff, tangentPoint, &sip);
}

---

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

• /home/jenkins-slave/snowflake/release/lsstsw/stack/Linux64/jointcal/15.0-6-ge2d9597+10/include/lsst/jointcal/SimplePolyModel.h
• /home/jenkins-slave/snowflake/release/lsstsw/stack/Linux64/jointcal/15.0-6-ge2d9597+10/src/SimplePolyModel.cc