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) More...
	ChipVisitAstrometryMapping (ChipVisitAstrometryMapping &&)=delete
ChipVisitAstrometryMapping &	operator= (ChipVisitAstrometryMapping const &)=delete
ChipVisitAstrometryMapping &	operator= (ChipVisitAstrometryMapping &&)=delete
std::size_t	getNpar () const
	Number of parameters in total. More...
void	getMappingIndices (IndexVector &indices) const
	Sets how this set of parameters (of length Npar()) map into the "grand" fit Expects that indices has enough space reserved. More...
void	computeTransformAndDerivatives (FatPoint const &where, FatPoint &outPoint, Eigen::MatrixX2d &H) const
	Actually applies the AstrometryMapping and evaluates the derivatives w.r.t the fitted parameters. More...
void	transformPosAndErrors (FatPoint const &where, FatPoint &outPoint) const
	The same as above but without the parameter derivatives (used to evaluate chi^2) More...
void	offsetParams (Eigen::VectorXd const &delta)
	Remember the error scale and freeze it. More...
AstrometryTransform const &	getTransform1 () const
	access to transforms More...
AstrometryTransform const &	getTransform2 () const
	access to transforms More...
void	positionDerivative (Point const &where, Eigen::Matrix2d &derivative, double epsilon) const
	Currently not implemented. More...
void	freezeErrorTransform ()
	Currently not implemented. More...

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 33 of file ChipVisitAstrometryMapping.cc.

        : _m1(chipMapping), _m2(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::unique_ptr<tmpVars>(new 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

virtual

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 62 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 119 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

virtual

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 45 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

virtual

Number of parameters in total.

Implements lsst::jointcal::AstrometryMapping.

Definition at line 43 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 )

inlinevirtual

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 const &  )

delete

operator=() [2/2]

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

delete

positionDerivative()

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

virtual

Currently not implemented.

Implements lsst::jointcal::AstrometryMapping.

Definition at line 107 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;
}

transformPosAndErrors()

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

virtual

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

Implements lsst::jointcal::AstrometryMapping.

Definition at line 101 of file ChipVisitAstrometryMapping.cc.

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

Friends And Related Function Documentation

ConstrainedAstrometryModel

friend class ConstrainedAstrometryModel

friend

Definition at line 84 of file ChipVisitAstrometryMapping.h.

---

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

• /j/snowflake/release/lsstsw/stack/Linux64/jointcal/17.0.1-17-gdae4c4a+8/include/lsst/jointcal/ChipVisitAstrometryMapping.h
• /j/snowflake/release/lsstsw/stack/Linux64/jointcal/17.0.1-17-gdae4c4a+8/src/ChipVisitAstrometryMapping.cc