LSST Applications  21.0.0-172-gfb10e10a+18fedfabac,22.0.0+297cba6710,22.0.0+80564b0ff1,22.0.0+8d77f4f51a,22.0.0+a28f4c53b1,22.0.0+dcf3732eb2,22.0.1-1-g7d6de66+2a20fdde0d,22.0.1-1-g8e32f31+297cba6710,22.0.1-1-geca5380+7fa3b7d9b6,22.0.1-12-g44dc1dc+2a20fdde0d,22.0.1-15-g6a90155+515f58c32b,22.0.1-16-g9282f48+790f5f2caa,22.0.1-2-g92698f7+dcf3732eb2,22.0.1-2-ga9b0f51+7fa3b7d9b6,22.0.1-2-gd1925c9+bf4f0e694f,22.0.1-24-g1ad7a390+a9625a72a8,22.0.1-25-g5bf6245+3ad8ecd50b,22.0.1-25-gb120d7b+8b5510f75f,22.0.1-27-g97737f7+2a20fdde0d,22.0.1-32-gf62ce7b1+aa4237961e,22.0.1-4-g0b3f228+2a20fdde0d,22.0.1-4-g243d05b+871c1b8305,22.0.1-4-g3a563be+32dcf1063f,22.0.1-4-g44f2e3d+9e4ab0f4fa,22.0.1-42-gca6935d93+ba5e5ca3eb,22.0.1-5-g15c806e+85460ae5f3,22.0.1-5-g58711c4+611d128589,22.0.1-5-g75bb458+99c117b92f,22.0.1-6-g1c63a23+7fa3b7d9b6,22.0.1-6-g50866e6+84ff5a128b,22.0.1-6-g8d3140d+720564cf76,22.0.1-6-gd805d02+cc5644f571,22.0.1-8-ge5750ce+85460ae5f3,master-g6e05de7fdc+babf819c66,master-g99da0e417a+8d77f4f51a,w.2021.48
LSST Data Management Base Package
Public Types | Public Member Functions | Static Public Member Functions | Static Public Attributes | Protected Attributes | List of all members
lsst::meas::base::PeakLikelihoodFluxAlgorithm Class Reference

A measurement algorithm that estimates the peak instrument flux, using a filtered image which has been convolved with its own PSF. More...

#include <PeakLikelihoodFlux.h>

Inheritance diagram for lsst::meas::base::PeakLikelihoodFluxAlgorithm:
lsst::meas::base::SimpleAlgorithm lsst::meas::base::SingleFrameAlgorithm lsst::meas::base::ForcedAlgorithm lsst::meas::base::BaseAlgorithm lsst::meas::base::BaseAlgorithm

Public Types

typedef PeakLikelihoodFluxControl Control
 A typedef to the Control object for this algorithm, defined above. More...
 

Public Member Functions

 PeakLikelihoodFluxAlgorithm (Control const &ctrl, std::string const &name, afw::table::Schema &schema)
 
virtual void measure (afw::table::SourceRecord &measRecord, afw::image::Exposure< float > const &exposure) const
 Called to measure a single child source in an image. More...
 
virtual void fail (afw::table::SourceRecord &measRecord, MeasurementError *error=nullptr) const
 Handle an exception thrown by the current algorithm by setting flags in the given record. More...
 
virtual void measureForced (afw::table::SourceRecord &measRecord, afw::image::Exposure< float > const &exposure, afw::table::SourceRecord const &refRecord, afw::geom::SkyWcs const &refWcs) const
 Called to measure a single child source in an image. More...
 
virtual void measureNForced (afw::table::SourceCatalog const &measCat, afw::image::Exposure< float > const &exposure, afw::table::SourceCatalog const &refRecord, afw::geom::SkyWcs const &refWcs) const
 Called to simultaneously measure all children in a deblend family, in a single image. More...
 
virtual void measureN (afw::table::SourceCatalog const &measCat, afw::image::Exposure< float > const &exposure) const
 Called to simultaneously measure all children in a deblend family, in a single image. More...
 
std::string getLogName () const
 

Static Public Member Functions

static FlagDefinitionList const & getFlagDefinitions ()
 

Static Public Attributes

static FlagDefinition const FAILURE = flagDefinitions.addFailureFlag()
 

Protected Attributes

std::string _logName
 

Detailed Description

A measurement algorithm that estimates the peak instrument flux, using a filtered image which has been convolved with its own PSF.

Definition at line 71 of file PeakLikelihoodFlux.h.

Member Typedef Documentation

◆ Control

typedef PeakLikelihoodFluxControl lsst::meas::base::PeakLikelihoodFluxAlgorithm::Control

A typedef to the Control object for this algorithm, defined above.

The control object contains the configuration parameters for this algorithm.

Definition at line 79 of file PeakLikelihoodFlux.h.

Constructor & Destructor Documentation

◆ PeakLikelihoodFluxAlgorithm()

lsst::meas::base::PeakLikelihoodFluxAlgorithm::PeakLikelihoodFluxAlgorithm ( Control const &  ctrl,
std::string const &  name,
afw::table::Schema &  schema 
)

Definition at line 179 of file PeakLikelihoodFlux.cc.

181  : _ctrl(ctrl),
182  _instFluxResultKey(
183  FluxResultKey::addFields(schema, name, "instFlux from PeakLikelihood Flux algorithm")),
184  _centroidExtractor(schema, name) {
185  _flagHandler = FlagHandler::addFields(schema, name, getFlagDefinitions());
186 }
name
table::Key< std::string > name
Definition: Amplifier.cc:116
schema
table::Schema schema
Definition: python.h:134
lsst::meas::base::FlagHandler::addFields
static FlagHandler addFields(afw::table::Schema &schema, std::string const &prefix, FlagDefinitionList const &flagDefs, FlagDefinitionList const &exclDefs=FlagDefinitionList::getEmptyList())
Add Flag fields to a schema, creating a FlagHandler object to manage them.
Definition: FlagHandler.cc:37
lsst::meas::base::FluxResultKey::addFields
static FluxResultKey addFields(afw::table::Schema &schema, std::string const &name, std::string const &doc)
Add a pair of _instFlux, _instFluxErr fields to a Schema, and return a FluxResultKey that points to t...
Definition: FluxUtilities.cc:36
lsst::meas::base::PeakLikelihoodFluxAlgorithm::getFlagDefinitions
static FlagDefinitionList const & getFlagDefinitions()
Definition: PeakLikelihoodFlux.cc:45

Member Function Documentation

◆ fail()

void lsst::meas::base::PeakLikelihoodFluxAlgorithm::fail ( afw::table::SourceRecord &  measRecord,
MeasurementError *  error = nullptr 
) const
virtual

Handle an exception thrown by the current algorithm by setting flags in the given record.

fail() is called by the measurement framework when an exception is allowed to propagate out of one the algorithm's measure() methods. It should generally set both a general failure flag for the algorithm as well as a specific flag indicating the error condition, if possible. To aid in this, if the exception was an instance of MeasurementError, it will be passed in, carrying information about what flag to set.

An algorithm can also to chose to set flags within its own measure() methods, and then just return, rather than throw an exception. However, fail() should be implemented even when all known failure modes do not throw exceptions, to ensure that unexpected exceptions thrown in lower-level code are properly handled.

Implements lsst::meas::base::BaseAlgorithm.

Definition at line 244 of file PeakLikelihoodFlux.cc.

244  {
245  _flagHandler.handleFailure(measRecord, error);
246 }
lsst::meas::base::FlagHandler::handleFailure
void handleFailure(afw::table::BaseRecord &record, MeasurementError const *error=nullptr) const
Handle an expected or unexpected Exception thrown by a measurement algorithm.
Definition: FlagHandler.cc:76

◆ getFlagDefinitions()

FlagDefinitionList const & lsst::meas::base::PeakLikelihoodFluxAlgorithm::getFlagDefinitions ( )
static

Definition at line 45 of file PeakLikelihoodFlux.cc.

45 { return flagDefinitions; }

◆ getLogName()

std::string lsst::meas::base::BaseAlgorithm::getLogName ( ) const
inlineinherited

Definition at line 66 of file Algorithm.h.

66 { return _logName; }

◆ measure()

void lsst::meas::base::PeakLikelihoodFluxAlgorithm::measure ( afw::table::SourceRecord &  measRecord,
afw::image::Exposure< float > const &  exposure 
) const
virtual

Called to measure a single child source in an image.

Before this method is called, all neighbors will be replaced with noise, using the outputs of the deblender. Outputs should be saved in the given SourceRecord, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

Given an image and a pixel position, return a Flux

Exceptions
pex::exceptions::InvalidParameterErrorif the exposure has no PSF.
pex::exceptions::RangeErrorif the warping (centering) kernel is not fully contained within the exposure.
pex::exceptions::RangeErrorif the center not within exposure. (This avoids insane center values from confusing the test for warping kernel within exposure).

Implements lsst::meas::base::SingleFrameAlgorithm.

Definition at line 188 of file PeakLikelihoodFlux.cc.

189  {
190  // get the value from the centroid slot only
191  geom::Point2D center = _centroidExtractor(measRecord, _flagHandler);
192  FluxResult result;
193  typedef afw::image::Exposure<float>::MaskedImageT MaskedImageT;
194  MaskedImageT const &mimage = exposure.getMaskedImage();
195 
206  if (!exposure.hasPsf()) {
207  throw LSST_EXCEPT(pex::exceptions::InvalidParameterError, "exposure has no PSF");
208  }
209  std::shared_ptr<afw::detection::Psf const> psfPtr = exposure.getPsf();
210  if (!geom::Box2D(mimage.getBBox()).contains(center)) {
211  std::ostringstream os;
212  os << "Center = " << center << " not in exposure bbox" << mimage.getBBox();
213  throw LSST_EXCEPT(pex::exceptions::RangeError, os.str());
214  }
215 
216  // compute parent index and fractional offset of ctrPix: the pixel closest to "center",
217  // the centroid of the source
218  std::pair<int, double> const xCtrPixParentIndFrac = afw::image::positionToIndex(center.getX(), true);
219  std::pair<int, double> const yCtrPixParentIndFrac = afw::image::positionToIndex(center.getY(), true);
220 
221  geom::Point2I ctrPixParentInd(xCtrPixParentIndFrac.first, yCtrPixParentIndFrac.first);
222  geom::Point2D ctrPixPos(afw::image::indexToPosition(ctrPixParentInd[0]),
223  afw::image::indexToPosition(ctrPixParentInd[1]));
224 
225  // compute weight = 1/sum(PSF^2) for PSF at ctrPix, where PSF is normalized to a sum of 1
226  PsfAttributes psfAttr(psfPtr, ctrPixParentInd);
227  double weight = psfAttr.computeEffectiveArea();
228 
229  /*
230  * Compute value of image at center of source, as shifted by a fractional pixel to center the source
231  * on ctrPix.
232  */
233  MaskedImageT::SinglePixel mimageCtrPix = computeShiftedValue(
234  mimage, _ctrl.warpingKernelName,
235  geom::Point2D(xCtrPixParentIndFrac.second, yCtrPixParentIndFrac.second), ctrPixParentInd);
236  double instFlux = mimageCtrPix.image() * weight;
237  double var = mimageCtrPix.variance() * weight * weight;
238  result.instFlux = instFlux;
239  result.instFluxErr = std::sqrt(var);
240  measRecord.set(_instFluxResultKey, result);
241  _flagHandler.setValue(measRecord, FAILURE.number, false);
242 }
result
py::object result
Definition: _schema.cc:429
LSST_EXCEPT
#define LSST_EXCEPT(type,...)
Create an exception with a given type.
Definition: Exception.h:48
os
std::ostream * os
Definition: Schema.cc:557
lsst::afw::image::Exposure< float >::MaskedImageT
MaskedImage< float, lsst::afw::image::MaskPixel, lsst::afw::image::VariancePixel > MaskedImageT
Definition: Exposure.h:74
lsst::geom::Box2D
A floating-point coordinate rectangle geometry.
Definition: Box.h:413
lsst::geom::Box2D::contains
bool contains(Point2D const &point) const noexcept
Return true if the box contains the point.
Definition: Box.cc:322
lsst::meas::base::FlagHandler::setValue
void setValue(afw::table::BaseRecord &record, std::size_t i, bool value) const
Set the flag field corresponding to the given flag index.
Definition: FlagHandler.h:262
lsst::meas::base::PeakLikelihoodFluxControl::warpingKernelName
std::string warpingKernelName
"Name of warping kernel (e.g. \"lanczos4") used to compute the peak" ;
Definition: PeakLikelihoodFlux.h:62
lsst::afw::image::indexToPosition
double indexToPosition(double ind)
Convert image index to image position.
Definition: ImageUtils.h:55
lsst::afw::image::positionToIndex
int positionToIndex(double pos)
Convert image position to nearest integer index.
Definition: ImageUtils.h:69
lsst::meas::base::computeShiftedValue
afw::image::MaskedImage< T >::SinglePixel computeShiftedValue(afw::image::MaskedImage< T > const &maskedImage, std::string const &warpingKernelName, geom::Point2D const &fracShift, geom::Point2I const &parentInd)
Compute the value of one pixel of an image after a fractional pixel shift Since we only want the valu...
Definition: PeakLikelihoodFlux.cc:134
std::sqrt
T sqrt(T... args)
weight
afw::table::Key< double > weight
Definition: CoaddBoundedField.cc:166

◆ measureForced()

virtual void lsst::meas::base::SimpleAlgorithm::measureForced ( afw::table::SourceRecord &  measRecord,
afw::image::Exposure< float > const &  exposure,
afw::table::SourceRecord const &  refRecord,
afw::geom::SkyWcs const &  refWcs 
) const
inlinevirtualinherited

Called to measure a single child source in an image.

Before this method is called, all neighbors will be replaced with noise, using the outputs of the deblender. Outputs should be saved in the given SourceRecord, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

Implements lsst::meas::base::ForcedAlgorithm.

Reimplemented in lsst::meas::extensions::photometryKron::KronFluxAlgorithm.

Definition at line 172 of file Algorithm.h.

175  {
176  measure(measRecord, exposure);
177  }
lsst::meas::base::SingleFrameAlgorithm::measure
virtual void measure(afw::table::SourceRecord &measRecord, afw::image::Exposure< float > const &exposure) const =0
Called to measure a single child source in an image.

◆ measureN()

void lsst::meas::base::SingleFrameAlgorithm::measureN ( afw::table::SourceCatalog const &  measCat,
afw::image::Exposure< float > const &  exposure 
) const
virtualinherited

Called to simultaneously measure all children in a deblend family, in a single image.

Outputs should be saved in the given SourceCatalog, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

The default implementation simply throws an exception, indicating that simultaneous measurement is not supported.

Definition at line 31 of file Algorithm.cc.

32  {
33  throw LSST_EXCEPT(pex::exceptions::LogicError, "measureN not implemented for this algorithm");
34 }

◆ measureNForced()

virtual void lsst::meas::base::SimpleAlgorithm::measureNForced ( afw::table::SourceCatalog const &  measCat,
afw::image::Exposure< float > const &  exposure,
afw::table::SourceCatalog const &  refRecord,
afw::geom::SkyWcs const &  refWcs 
) const
inlinevirtualinherited

Called to simultaneously measure all children in a deblend family, in a single image.

Outputs should be saved in the given SourceCatalog, which can also be used to obtain centroid (see SafeCentroidExtractor) and shape (see SafeShapeExtractor) information.

The default implementation simply throws an exception, indicating that simultaneous measurement is not supported.

Reimplemented from lsst::meas::base::ForcedAlgorithm.

Definition at line 179 of file Algorithm.h.

182  {
183  measureN(measCat, exposure);
184  }
lsst::meas::base::SingleFrameAlgorithm::measureN
virtual void measureN(afw::table::SourceCatalog const &measCat, afw::image::Exposure< float > const &exposure) const
Called to simultaneously measure all children in a deblend family, in a single image.
Definition: Algorithm.cc:31

Member Data Documentation

◆ _logName

std::string lsst::meas::base::BaseAlgorithm::_logName
protectedinherited

Definition at line 69 of file Algorithm.h.

◆ FAILURE

FlagDefinition const lsst::meas::base::PeakLikelihoodFluxAlgorithm::FAILURE = flagDefinitions.addFailureFlag()
static

Definition at line 75 of file PeakLikelihoodFlux.h.

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