lsst::jointcal::ChipVisitAstrometryMapping Class Reference

The mapping with two transforms in a row. More...

#include <ChipVisitAstrometryMapping.h>

Inheritance diagram for lsst::jointcal::ChipVisitAstrometryMapping:

Public Member Functions
	ChipVisitAstrometryMapping (std::shared_ptr< SimpleAstrometryMapping > chipMapping, std::shared_ptr< SimpleAstrometryMapping > visitMapping)
	ChipVisitAstrometryMapping (ChipVisitAstrometryMapping const &)=delete
	No copy or move: there is only ever one instance of a given model (i.e.. per ccd+visit)
	ChipVisitAstrometryMapping (ChipVisitAstrometryMapping &&)=delete
ChipVisitAstrometryMapping &	operator= (ChipVisitAstrometryMapping const &)=delete
ChipVisitAstrometryMapping &	operator= (ChipVisitAstrometryMapping &&)=delete
std::size_t	getNpar () const override
	Number of parameters in total.
void	getMappingIndices (IndexVector &indices) const override
	Sets how this set of parameters (of length Npar()) map into the "grand" fit Expects that indices has enough space reserved.
void	computeTransformAndDerivatives (FatPoint const &where, FatPoint &outPoint, Eigen::MatrixX2d &H) const override
	Actually applies the AstrometryMapping and evaluates the derivatives w.r.t the fitted parameters.
void	transformPosAndErrors (FatPoint const &where, FatPoint &outPoint) const override
	The same as above but without the parameter derivatives (used to evaluate chi^2)
void	offsetParams (Eigen::VectorXd const &delta) override
	Remember the error scale and freeze it.
AstrometryTransform const &	getTransform1 () const
	access to transforms
AstrometryTransform const &	getTransform2 () const
	access to transforms
void	positionDerivative (Point const &where, Eigen::Matrix2d &derivative, double epsilon) const override
	The derivative w.r.t. position.
void	freezeErrorTransform ()
	Currently not implemented.
void	print (std::ostream &out) const override
	Print a string representation of the contents of this mapping, for debugging.

Friends
class	ConstrainedAstrometryModel

Detailed Description

The mapping with two transforms in a row.

Definition at line 38 of file ChipVisitAstrometryMapping.h.

Constructor & Destructor Documentation

ChipVisitAstrometryMapping() [1/3]

lsst::jointcal::ChipVisitAstrometryMapping::ChipVisitAstrometryMapping	(	std::shared_ptr< SimpleAstrometryMapping >	chipMapping,
		std::shared_ptr< SimpleAstrometryMapping >	visitMapping )

Definition at line 36 of file ChipVisitAstrometryMapping.cc.

        : _m1(std::move(chipMapping)), _m2(std::move(visitMapping)) {
    /* Allocate the record of temporary variables, so that they are not
       allocated at every call. This is hidden behind a pointer in order
       to be allowed to alter them in a const routine. */
    tmp = std::make_unique<tmpVars>();
    setWhatToFit(true, true);
}

ChipVisitAstrometryMapping() [2/3]

lsst::jointcal::ChipVisitAstrometryMapping::ChipVisitAstrometryMapping ( ChipVisitAstrometryMapping const & )

delete

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

ChipVisitAstrometryMapping() [3/3]

lsst::jointcal::ChipVisitAstrometryMapping::ChipVisitAstrometryMapping ( ChipVisitAstrometryMapping && )

delete

Member Function Documentation

computeTransformAndDerivatives()

void lsst::jointcal::ChipVisitAstrometryMapping::computeTransformAndDerivatives ( FatPoint const & where, FatPoint & outPoint, Eigen::MatrixX2d & H ) const

overridevirtual

Actually applies the AstrometryMapping and evaluates the derivatives w.r.t the fitted parameters.

This is grouped into a single call because for most models, evaluating the derivatives w.r.T parameters is not much longer than just transforming

Implements lsst::jointcal::AstrometryMapping.

Definition at line 65 of file ChipVisitAstrometryMapping.cc.

                                                                                         {
    // not true in general. Will crash if H is too small.
    //  assert(H.cols()==Npar());
 
    FatPoint pMid;
    // don't need errors there but no Mapping::Transform() routine.
 
    if (_nPar1) {
        _m1->computeTransformAndDerivatives(where, pMid, tmp->h1);
        // the last argument is epsilon and is not used for polynomials
        _m2->positionDerivative(pMid, tmp->dt2dx, 1e-4);
        H.block(0, 0, _nPar1, 2) = tmp->h1 * tmp->dt2dx;
    } else
        _m1->transformPosAndErrors(where, pMid);
    if (_nPar2) {
        _m2->computeTransformAndDerivatives(pMid, outPoint, tmp->h2);
        H.block(_nPar1, 0, _nPar2, 2) = tmp->h2;
    } else
        _m2->transformPosAndErrors(pMid, outPoint);
}

freezeErrorTransform()

void lsst::jointcal::ChipVisitAstrometryMapping::freezeErrorTransform

(

)

Currently not implemented.

Definition at line 122 of file ChipVisitAstrometryMapping.cc.

                                                      {
    throw LSST_EXCEPT(pexExcept::TypeError,
                      " The routine ChipVisitAstrometryMapping::freezeErrorTransform() was thought to be "
                      "useless and is not implemented (yet)");
}

getMappingIndices()

void lsst::jointcal::ChipVisitAstrometryMapping::getMappingIndices ( IndexVector & indices ) const

overridevirtual

Sets how this set of parameters (of length Npar()) map into the "grand" fit Expects that indices has enough space reserved.

Implements lsst::jointcal::AstrometryMapping.

Definition at line 48 of file ChipVisitAstrometryMapping.cc.

                                                                             {
    std::size_t npar = getNpar();
    if (indices.size() < npar) indices.resize(npar);
    // in case we are only fitting one of the two transforms
    if (_nPar1)
        _m1->getMappingIndices(indices);
    else if (_nPar2) {
        _m2->getMappingIndices(indices);
        return;
    }
    // if we get here we are fitting both
    // there is probably a more elegant way to feed a subpart of a std::vector
    IndexVector ind2(_nPar2);
    _m2->getMappingIndices(ind2);
    for (Eigen::Index k = 0; k < _nPar2; ++k) indices.at(k + _nPar1) = ind2.at(k);
}

getNpar()

std::size_t lsst::jointcal::ChipVisitAstrometryMapping::getNpar ( ) const

overridevirtual

Number of parameters in total.

Implements lsst::jointcal::AstrometryMapping.

Definition at line 46 of file ChipVisitAstrometryMapping.cc.

{ return _nPar1 + _nPar2; }

getTransform1()

AstrometryTransform const & lsst::jointcal::ChipVisitAstrometryMapping::getTransform1 ( ) const

inline

access to transforms

Definition at line 72 of file ChipVisitAstrometryMapping.h.

{ return _m1->getTransform(); }

getTransform2()

AstrometryTransform const & lsst::jointcal::ChipVisitAstrometryMapping::getTransform2 ( ) const

inline

access to transforms

Definition at line 75 of file ChipVisitAstrometryMapping.h.

{ return _m2->getTransform(); }

offsetParams()

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

inlineoverridevirtual

Remember the error scale and freeze it.

Note

this routine is not used when fitting (the Model manages the mappings separately), but can be useful for debugging

Implements lsst::jointcal::AstrometryMapping.

Definition at line 66 of file ChipVisitAstrometryMapping.h.

                                                           {
        _m1->offsetParams(delta.segment(_m1->getIndex(), _m1->getNpar()));
        _m2->offsetParams(delta.segment(_m2->getIndex() + _m1->getNpar(), _m2->getNpar()));
    }

operator=() [1/2]

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

delete

operator=() [2/2]

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

delete

positionDerivative()

void lsst::jointcal::ChipVisitAstrometryMapping::positionDerivative ( Point const & where, Eigen::Matrix2d & derivative, double epsilon ) const

overridevirtual

The derivative w.r.t. position.

Implements lsst::jointcal::AstrometryMapping.

Definition at line 110 of file ChipVisitAstrometryMapping.cc.

                                                                          {
    Eigen::Matrix2d d1, d2;  // seems that it does not trigger dynamic allocation
    _m1->positionDerivative(where, d1, 1e-4);
    FatPoint pMid;
    _m1->transformPosAndErrors(where, pMid);
    _m2->positionDerivative(pMid, d2, 1e-4);
    /* The following line is not a mistake. It is a consequence
       of chosing derivative(0,1) = d(y_out)/d x_in. */
    derivative = d1 * d2;
}

print()

void lsst::jointcal::ChipVisitAstrometryMapping::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 mapping.

Implements lsst::jointcal::AstrometryMapping.

Definition at line 128 of file ChipVisitAstrometryMapping.cc.

                                                            {
    out << "Composed Astrometry Mapping:" << std::endl;
    out << "Sensor f(x,y)->(u,v): " << *_m1 << std::endl;
    out << "Visit f(u,v)->alpha,delta: " << *_m2 << std::endl;
}

transformPosAndErrors()

void lsst::jointcal::ChipVisitAstrometryMapping::transformPosAndErrors ( FatPoint const & where, FatPoint & outPoint ) const

overridevirtual

The same as above but without the parameter derivatives (used to evaluate chi^2)

Implements lsst::jointcal::AstrometryMapping.

Definition at line 104 of file ChipVisitAstrometryMapping.cc.

                                                                                                      {
    FatPoint pMid;
    _m1->transformPosAndErrors(where, pMid);
    _m2->transformPosAndErrors(pMid, outPoint);
}

Friends And Related Symbol Documentation

ConstrainedAstrometryModel

friend class ConstrainedAstrometryModel

friend

Definition at line 85 of file ChipVisitAstrometryMapping.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+e2bd23ab8b/include/lsst/jointcal/ChipVisitAstrometryMapping.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/jointcal/g82479be7b0+e2bd23ab8b/src/ChipVisitAstrometryMapping.cc