lsst::ip::diffim::detail::KernelSumVisitor< PixelT > Class Template Reference

A class to accumulate kernel sums across SpatialCells. More...

#include <KernelSumVisitor.h>

Inheritance diagram for lsst::ip::diffim::detail::KernelSumVisitor< PixelT >:

Public Types
enum	Mode { AGGREGATE = 0, REJECT = 1 }
typedef boost::shared_ptr < KernelSumVisitor< PixelT > >	Ptr

Public Member Functions
	KernelSumVisitor (lsst::pex::policy::Policy const &policy)
virtual	~KernelSumVisitor ()
void	setMode (Mode mode)
int	getNRejected ()
double	getkSumMean ()
double	getkSumStd ()
double	getdkSumMax ()
int	getkSumNpts ()
void	resetKernelSum ()
void	processCandidate (lsst::afw::math::SpatialCellCandidate *candidate)
void	processKsumDistribution ()
Public Member Functions inherited from lsst::afw::math::CandidateVisitor
	CandidateVisitor ()
virtual	~CandidateVisitor ()
virtual void	reset ()

Private Attributes
Mode	_mode
	Processing mode; AGGREGATE or REJECT. More...
std::vector< double >	_kSums
	List of all candidate kernel sums. More...
double	_kSumMean
	Clipped mean of the kernel sums. More...
double	_kSumStd
	Clipped standard deviation of kernel sums. More...
double	_dkSumMax
	Maximum acceptable deviation from mean sum. More...
int	_kSumNpts
	Number of points used in the statistics. More...
int	_nRejected
	Number of candidates rejected during processCandidate() More...
lsst::pex::policy::Policy	_policy
	Policy controlling behavior. More...

Detailed Description

template<typename PixelT>
class lsst::ip::diffim::detail::KernelSumVisitor< PixelT >

A class to accumulate kernel sums across SpatialCells.

   Policy::Ptr policy(new Policy);
   policy->set("kernelSumClipping", false);
   policy->set("maxKsumSigma", 3.0);

   detail::KernelSumVisitor<PixelT> kernelSumVisitor(*policy);
   kernelSumVisitor.reset();
   kernelSumVisitor.setMode(detail::KernelSumVisitor<PixelT>::AGGREGATE);
   kernelCells.visitCandidates(&kernelSumVisitor, nStarPerCell);
   kernelSumVisitor.processKsumDistribution();
   kernelSumVisitor.setMode(detail::KernelSumVisitor<PixelT>::REJECT);
   kernelCells.visitCandidates(&kernelSumVisitor, nStarPerCell);
   int nRejected = kernelSumVisitor.getNRejected();
* 

Note

The class has 2 processing modes; the first AGGREGATES kernel sums across all candidates. You must the process the distribution to set member variables representing the mean and standard deviation of the kernel sums. The second mode then REJECTs candidates with kernel sums outside the acceptable range (set by the policy). It does this by setting candidate status to afwMath::SpatialCellCandidate::BAD. In this mode it also accumulates the number of candidates it sets as bad.

The statistics call calculates sigma-clipped values (afwMath::MEANCLIP, afwMath::STDEVCLIP)

Definition at line 26 of file KernelSumVisitor.h.

Member Typedef Documentation

template<typename PixelT >

typedef boost::shared_ptr<KernelSumVisitor<PixelT> > lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::Ptr

Definition at line 28 of file KernelSumVisitor.h.

Member Enumeration Documentation

template<typename PixelT >

enum lsst::ip::diffim::detail::KernelSumVisitor::Mode

Enumerator
AGGREGATE
REJECT

Definition at line 30 of file KernelSumVisitor.h.

{AGGREGATE = 0, REJECT = 1};

Constructor & Destructor Documentation

template<typename PixelT >

lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::KernelSumVisitor

(

lsst::pex::policy::Policy const &

policy

)

Parameters

policy

Policy file directing behavior

Definition at line 66 of file KernelSumVisitor.cc.

          :
        afwMath::CandidateVisitor(),
        _mode(AGGREGATE),
        _kSums(std::vector<double>()),
        _kSumMean(0.),
        _kSumStd(0.),
        _dkSumMax(0.),
        _kSumNpts(0),
        _nRejected(0),
        _policy(policy) 
    {};

template<typename PixelT >

virtual lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::~KernelSumVisitor ( )

inlinevirtual

Definition at line 33 of file KernelSumVisitor.h.

{};

Member Function Documentation

template<typename PixelT >

double lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::getdkSumMax ( )

inline

Definition at line 39 of file KernelSumVisitor.h.

{return _dkSumMax;}

template<typename PixelT >

double lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::getkSumMean ( )

inline

Definition at line 37 of file KernelSumVisitor.h.

{return _kSumMean;}

template<typename PixelT >

int lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::getkSumNpts ( )

inline

Definition at line 40 of file KernelSumVisitor.h.

{return _kSumNpts;}

template<typename PixelT >

double lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::getkSumStd ( )

inline

Definition at line 38 of file KernelSumVisitor.h.

{return _kSumStd;}

template<typename PixelT >

int lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::getNRejected ( )

inline

Definition at line 36 of file KernelSumVisitor.h.

{return _nRejected;}

template<typename PixelT >

void lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::processCandidate ( lsst::afw::math::SpatialCellCandidate *  candidate )

virtual

Reimplemented from lsst::afw::math::CandidateVisitor.

Definition at line 91 of file KernelSumVisitor.cc.

                                                                {

        KernelCandidate<PixelT> *kCandidate = dynamic_cast<KernelCandidate<PixelT> *>(candidate);
        if (kCandidate == NULL) {
            throw LSST_EXCEPT(pexExcept::LogicError,
                              "Failed to cast SpatialCellCandidate to KernelCandidate");
        }
        pexLogging::TTrace<6>("lsst.ip.diffim.KernelSumVisitor.processCandidate", 
                              "Processing candidate %d, mode %d", kCandidate->getId(), _mode);
        
        /* Grab all kernel sums and look for outliers */
        if (_mode == AGGREGATE) {
            _kSums.push_back(kCandidate->getKernelSolution(KernelCandidate<PixelT>::ORIG)->getKsum());
        }
        else if (_mode == REJECT) {
            if (_policy.getBool("kernelSumClipping")) {
                double kSum = 
                    kCandidate->getKernelSolution(KernelCandidate<PixelT>::ORIG)->getKsum();

                if (fabs(kSum - _kSumMean) > _dkSumMax) {
                    kCandidate->setStatus(afwMath::SpatialCellCandidate::BAD);
                    pexLogging::TTrace<4>("lsst.ip.diffim.KernelSumVisitor.processCandidate", 
                                          "Rejecting candidate %d; bad source kernel sum : (%.2f)",
                                          kCandidate->getId(),
                                          kSum);
                    _nRejected += 1;
                }
            }
            else {
                pexLogging::TTrace<6>("lsst.ip.diffim.KernelSumVisitor.processCandidate", 
                                      "Sigma clipping not enabled");
            }
        }
    }

template<typename PixelT >

void lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::processKsumDistribution

(

)

Definition at line 128 of file KernelSumVisitor.cc.

                                                           {
        if (_kSums.size() == 0) {
            throw LSST_EXCEPT(pexExcept::Exception, 
                              "Unable to determine kernel sum; 0 candidates");
        }
        else if (_kSums.size() == 1) {
            pexLogging::TTrace<2>("lsst.ip.diffim.KernelSumVisitor.processKsumDistribution", 
                                  "WARNING: only 1 kernel candidate");
            
            _kSumMean = _kSums[0];
            _kSumStd  = 0.0;
            _kSumNpts = 1;
        }
        else {
            try {
                afwMath::Statistics stats = afwMath::makeStatistics(_kSums, 
                                                                    afwMath::NPOINT | 
                                                                    afwMath::MEANCLIP | 
                                                                    afwMath::STDEVCLIP); 
                _kSumMean = stats.getValue(afwMath::MEANCLIP);
                _kSumStd  = stats.getValue(afwMath::STDEVCLIP);
                _kSumNpts = static_cast<int>(stats.getValue(afwMath::NPOINT));
            } catch (pexExcept::Exception &e) {
                LSST_EXCEPT_ADD(e, "Unable to calculate kernel sum statistics");
                throw e;
            }
            if (std::isnan(_kSumMean)) {
                throw LSST_EXCEPT(pexExcept::Exception, 
                                  str(boost::format("Mean kernel sum returns NaN (%d points)") 
                                      % _kSumNpts));
            }
            if (std::isnan(_kSumStd)) {
                throw LSST_EXCEPT(pexExcept::Exception, 
                                  str(boost::format("Kernel sum stdev returns NaN (%d points)") 
                                      % _kSumNpts));
            }
        }
        _dkSumMax = _policy.getDouble("maxKsumSigma") * _kSumStd;
        pexLogging::TTrace<2>("lsst.ip.diffim.KernelSumVisitor.processCandidate", 
                              "Kernel Sum Distribution : %.3f +/- %.3f (%d points)", 
                              _kSumMean, _kSumStd, _kSumNpts);
    }

template<typename PixelT >

void lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::resetKernelSum

(

)

Definition at line 81 of file KernelSumVisitor.cc.

                                                  {
        _kSums.clear();
        _kSumMean =  0.;
        _kSumStd  =  0.;
        _dkSumMax =  0.;
        _kSumNpts =  0;
        _nRejected = 0;
    }

template<typename PixelT >

void lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::setMode ( Mode  mode )

inline

Definition at line 35 of file KernelSumVisitor.h.

{_mode = mode;}

Member Data Documentation

template<typename PixelT >

double lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_dkSumMax

private

Maximum acceptable deviation from mean sum.

Definition at line 51 of file KernelSumVisitor.h.

template<typename PixelT >

double lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_kSumMean

private

Clipped mean of the kernel sums.

Definition at line 49 of file KernelSumVisitor.h.

template<typename PixelT >

int lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_kSumNpts

private

Number of points used in the statistics.

Definition at line 52 of file KernelSumVisitor.h.

template<typename PixelT >

std::vector<double> lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_kSums

private

List of all candidate kernel sums.

Definition at line 48 of file KernelSumVisitor.h.

template<typename PixelT >

double lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_kSumStd

private

Clipped standard deviation of kernel sums.

Definition at line 50 of file KernelSumVisitor.h.

template<typename PixelT >

Mode lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_mode

private

Processing mode; AGGREGATE or REJECT.

Definition at line 47 of file KernelSumVisitor.h.

template<typename PixelT >

int lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_nRejected

private

Number of candidates rejected during processCandidate()

Definition at line 53 of file KernelSumVisitor.h.

template<typename PixelT >

lsst::pex::policy::Policy lsst::ip::diffim::detail::KernelSumVisitor< PixelT >::_policy

private

Policy controlling behavior.

Definition at line 54 of file KernelSumVisitor.h.

---

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

• /home/lsstsw/stack/Linux64/ip_diffim/11.0+1/include/lsst/ip/diffim/KernelSumVisitor.h
• /home/lsstsw/stack/Linux64/ip_diffim/11.0+1/src/KernelSumVisitor.cc