lsst::afw::math::FixedKernel Class Reference

A kernel created from an Image. More...

#include <Kernel.h>

Inheritance diagram for lsst::afw::math::FixedKernel:

Classes
class	Factory

Public Types
using	Pixel = double
using	SpatialFunctionPtr = std::shared_ptr<lsst::afw::math::Function2<double>>
using	SpatialFunction = lsst::afw::math::Function2<double>
using	NullSpatialFunction = lsst::afw::math::NullFunction2<double>
using	kernel_fill_factor = generic_kernel_tag

Public Member Functions
	FixedKernel ()
	Construct an empty FixedKernel of size 0x0.
	FixedKernel (lsst::afw::image::Image< Pixel > const &image)
	Construct a FixedKernel from an image.
	FixedKernel (lsst::afw::math::Kernel const &kernel, lsst::geom::Point2D const &pos)
	Construct a FixedKernel from a generic Kernel.
	FixedKernel (const FixedKernel &)=delete
	FixedKernel (FixedKernel &&)=delete
FixedKernel &	operator= (const FixedKernel &)=delete
FixedKernel &	operator= (FixedKernel &&)=delete
	~FixedKernel () override=default
std::shared_ptr< Kernel >	clone () const override
	Return a pointer to a deep copy of this kernel.
std::shared_ptr< Kernel >	resized (int width, int height) const override
	Return a pointer to a clone with specified kernel dimensions.
std::string	toString (std::string const &prefix="") const override
	Return a string representation of the kernel.
virtual Pixel	getSum () const
bool	isPersistable () const noexcept override
	Return true if this particular object can be persisted using afw::table::io.
double	computeImage (lsst::afw::image::Image< Pixel > &image, bool doNormalize, double x=0.0, double y=0.0) const
	Compute an image (pixellized representation of the kernel) in place.
lsst::geom::Extent2I const	getDimensions () const
	Return the Kernel's dimensions (width, height)
void	setDimensions (lsst::geom::Extent2I dims)
void	setWidth (int width)
void	setHeight (int height)
int	getWidth () const
	Return the Kernel's width.
int	getHeight () const
	Return the Kernel's height.
lsst::geom::Point2I	getCtr () const
	Return index of kernel's center.
lsst::geom::Box2I	getBBox () const
	return parent bounding box, with XY0 = -center
unsigned int	getNKernelParameters () const
	Return the number of kernel parameters (0 if none)
int	getNSpatialParameters () const
	Return the number of spatial parameters (0 if not spatially varying)
SpatialFunctionPtr	getSpatialFunction (unsigned int index) const
	Return a clone of the specified spatial function (one component of the spatial model)
std::vector< SpatialFunctionPtr >	getSpatialFunctionList () const
	Return a list of clones of the spatial functions.
virtual double	getKernelParameter (unsigned int i) const
	Return a particular Kernel Parameter (no bounds checking).
virtual std::vector< double >	getKernelParameters () const
	Return the current kernel parameters.
lsst::geom::Box2I	growBBox (lsst::geom::Box2I const &bbox) const
	Given a bounding box for pixels one wishes to compute by convolving an image with this kernel, return the bounding box of pixels that must be accessed on the image to be convolved.
lsst::geom::Box2I	shrinkBBox (lsst::geom::Box2I const &bbox) const
	Given a bounding box for an image one wishes to convolve with this kernel, return the bounding box for the region of pixels that can be computed.
void	setCtr (lsst::geom::Point2I ctr)
	Set index of kernel's center.
std::vector< std::vector< double > >	getSpatialParameters () const
	Return the spatial parameters parameters (an empty vector if not spatially varying)
bool	isSpatiallyVarying () const
	Return true iff the kernel is spatially varying (has a spatial function)
void	setKernelParameters (std::vector< double > const &params)
	Set the kernel parameters of a spatially invariant kernel.
void	setKernelParameters (std::pair< double, double > const &params)
	Set the kernel parameters of a 2-component spatially invariant kernel.
void	setSpatialParameters (const std::vector< std::vector< double > > params)
	Set the parameters of all spatial functions.
void	computeKernelParametersFromSpatialModel (std::vector< double > &kernelParams, double x, double y) const
	Compute the kernel parameters at a specified point.
virtual void	computeCache (int const)
	Compute a cache of Kernel values, if desired.
virtual int	getCacheSize () const
	Get the current size of the kernel cache (0 if none or if caches not supported)
void	writeFits (std::string const &fileName, std::string const &mode="w") const
	Write the object to a regular FITS file.
void	writeFits (fits::MemFileManager &manager, std::string const &mode="w") const
	Write the object to a FITS image in memory.
void	writeFits (fits::Fits &fitsfile) const
	Write the object to an already-open FITS object.

Static Public Member Functions
static std::shared_ptr< FixedKernel >	readFits (fits::Fits &fitsfile)
	Read an object from an already open FITS object.
static std::shared_ptr< FixedKernel >	readFits (std::string const &fileName, int hdu=fits::DEFAULT_HDU)
	Read an object from a regular FITS file.
static std::shared_ptr< FixedKernel >	readFits (fits::MemFileManager &manager, int hdu=fits::DEFAULT_HDU)
	Read an object from a FITS file in memory.
static std::shared_ptr< FixedKernel >	dynamicCast (std::shared_ptr< Persistable > const &ptr)
	Dynamically cast a shared_ptr.
static std::shared_ptr< Kernel >	readFits (fits::Fits &fitsfile)
	Read an object from an already open FITS object.
static std::shared_ptr< Kernel >	readFits (std::string const &fileName, int hdu=fits::DEFAULT_HDU)
	Read an object from a regular FITS file.
static std::shared_ptr< Kernel >	readFits (fits::MemFileManager &manager, int hdu=fits::DEFAULT_HDU)
	Read an object from a FITS file in memory.
static std::shared_ptr< Kernel >	dynamicCast (std::shared_ptr< Persistable > const &ptr)
	Dynamically cast a shared_ptr.

Protected Types
using	OutputArchiveHandle = io::OutputArchiveHandle

Protected Member Functions
double	doComputeImage (lsst::afw::image::Image< Pixel > &image, bool doNormalize) const override
	Low-level version of computeImage.
std::string	getPersistenceName () const override
	Return the unique name used to persist this object and look up its factory.
void	write (OutputArchiveHandle &handle) const override
	Write the object to one or more catalogs.
std::string	getPythonModule () const override
	Return the fully-qualified Python module that should be imported to guarantee that its factory is registered.
virtual void	setKernelParameter (unsigned int ind, double value) const
	Set one kernel parameter.
void	setKernelParametersFromSpatialModel (double x, double y) const
	Set the kernel parameters from the spatial model (if any).

Protected Attributes
std::vector< SpatialFunctionPtr >	_spatialFunctionList

Detailed Description

A kernel created from an Image.

It has no adjustable parameters and so cannot be spatially varying.

Definition at line 471 of file Kernel.h.

Member Typedef Documentation

kernel_fill_factor

using lsst::afw::math::Kernel::kernel_fill_factor = generic_kernel_tag

inherited

Definition at line 118 of file Kernel.h.

NullSpatialFunction

using lsst::afw::math::Kernel::NullSpatialFunction = lsst::afw::math::NullFunction2<double>

inherited

Definition at line 115 of file Kernel.h.

OutputArchiveHandle

using lsst::afw::table::io::Persistable::OutputArchiveHandle = io::OutputArchiveHandle

protectedinherited

Definition at line 108 of file Persistable.h.

Pixel

using lsst::afw::math::Kernel::Pixel = double

inherited

Definition at line 112 of file Kernel.h.

SpatialFunction

using lsst::afw::math::Kernel::SpatialFunction = lsst::afw::math::Function2<double>

inherited

Definition at line 114 of file Kernel.h.

SpatialFunctionPtr

using lsst::afw::math::Kernel::SpatialFunctionPtr = std::shared_ptr<lsst::afw::math::Function2<double>>

inherited

Definition at line 113 of file Kernel.h.

Constructor & Destructor Documentation

FixedKernel() [1/5]

lsst::afw::math::FixedKernel::FixedKernel ( )

explicit

Construct an empty FixedKernel of size 0x0.

Definition at line 43 of file FixedKernel.cc.

: Kernel(), _image(), _sum(0) {}

FixedKernel() [2/5]

lsst::afw::math::FixedKernel::FixedKernel ( lsst::afw::image::Image< Pixel > const & image )

explicit

Construct a FixedKernel from an image.

Parameters

image

image for kernel

Definition at line 45 of file FixedKernel.cc.

        : Kernel(image.getWidth(), image.getHeight(), 0), _image(image, true), _sum(0) {
    using XIter = image::Image<Pixel>::x_iterator;
    double imSum = 0.0;
    for (int y = 0; y != image.getHeight(); ++y) {
        for (XIter imPtr = image.row_begin(y), imEnd = image.row_end(y); imPtr != imEnd; ++imPtr) {
            imSum += *imPtr;
        }
    }
    this->_sum = imSum;
}

FixedKernel() [3/5]

lsst::afw::math::FixedKernel::FixedKernel ( lsst::afw::math::Kernel const & kernel, lsst::geom::Point2D const & pos )

explicit

Construct a FixedKernel from a generic Kernel.

Parameters

kernel	Kernel to convert to Fixed
pos	desired position

Definition at line 57 of file FixedKernel.cc.

        : Kernel(kernel.getWidth(), kernel.getHeight(), 0), _image(kernel.getDimensions()), _sum(0) {
    _sum = kernel.computeImage(_image, false, pos[0], pos[1]);
}

FixedKernel() [4/5]

lsst::afw::math::FixedKernel::FixedKernel ( const FixedKernel & )

delete

FixedKernel() [5/5]

lsst::afw::math::FixedKernel::FixedKernel ( FixedKernel && )

delete

~FixedKernel()

lsst::afw::math::FixedKernel::~FixedKernel ( )

overridedefault

Member Function Documentation

clone()

std::shared_ptr< Kernel > lsst::afw::math::FixedKernel::clone ( ) const

overridevirtual

Return a pointer to a deep copy of this kernel.

This kernel exists instead of a copy constructor so one can obtain a copy of an actual kernel instead of a useless copy of the base class.

Every kernel subclass must override this method.

Returns

a pointer to a deep copy of the kernel

Implements lsst::afw::math::Kernel.

Definition at line 62 of file FixedKernel.cc.

                                               {
    std::shared_ptr<Kernel> retPtr(new FixedKernel(_image));
    retPtr->setCtr(this->getCtr());
    return retPtr;
}

computeCache()

virtual void lsst::afw::math::Kernel::computeCache ( int const )

inlinevirtualinherited

Compute a cache of Kernel values, if desired.

Warning

: few kernel classes actually support this, in which case this is a no-op and getCacheSize always returns 0.

Reimplemented in lsst::afw::math::SeparableKernel.

Definition at line 397 of file Kernel.h.

      {}

computeImage()

double lsst::afw::math::Kernel::computeImage ( lsst::afw::image::Image< Pixel > & image, bool doNormalize, double x = 0.0, double y = 0.0 ) const

inherited

Compute an image (pixellized representation of the kernel) in place.

Parameters

image	image whose pixels are to be set (output); xy0 of the image will be set to -kernel.getCtr()
doNormalize	normalize the image (so sum is 1)?
x	x (column position) at which to compute spatial function
y	y (row position) at which to compute spatial function

Returns

The kernel sum

Exceptions

lsst::pex::exceptions::InvalidParameterError	if the image is the wrong size
lsst::pex::exceptions::OverflowError	if doNormalize is true and the kernel sum is exactly 0

Note

computeNewImage has been retired; it doesn't need to be a member

Definition at line 76 of file Kernel.cc.

                                                                                                {
    if (image.getDimensions() != this->getDimensions()) {
        std::ostringstream os;
        os << "image dimensions = ( " << image.getWidth() << ", " << image.getHeight() << ") != ("
           << this->getWidth() << ", " << this->getHeight() << ") = kernel dimensions";
        throw LSST_EXCEPT(pexExcept::InvalidParameterError, os.str());
    }
    image.setXY0(-_ctrX, -_ctrY);
    if (this->isSpatiallyVarying()) {
        this->setKernelParametersFromSpatialModel(x, y);
    }
    return doComputeImage(image, doNormalize);
}

computeKernelParametersFromSpatialModel()

void lsst::afw::math::Kernel::computeKernelParametersFromSpatialModel ( std::vector< double > & kernelParams, double x, double y ) const

inherited

Compute the kernel parameters at a specified point.

Warning: this is a low-level function that assumes kernelParams is the right length. It will fail in unpredictable ways if that condition is not met.

Definition at line 135 of file Kernel.cc.

                                                                     {
    std::vector<double>::iterator paramIter = kernelParams.begin();
    std::vector<SpatialFunctionPtr>::const_iterator funcIter = _spatialFunctionList.begin();
    for (; funcIter != _spatialFunctionList.end(); ++funcIter, ++paramIter) {
        *paramIter = (*(*funcIter))(x, y);
    }
}

doComputeImage()

double lsst::afw::math::FixedKernel::doComputeImage ( lsst::afw::image::Image< Pixel > & image, bool doNormalize ) const

overrideprotectedvirtual

Low-level version of computeImage.

Before this is called the image dimensions are checked, the image's xy0 is set and the kernel's parameters are set. This routine sets the pixels, including normalization if requested.

Parameters

image	image whose pixels are to be set (output)
doNormalize	normalize the image (so sum is 1)?

Returns

The kernel sum

Implements lsst::afw::math::Kernel.

Definition at line 105 of file FixedKernel.cc.

                                                                                   {
    double multFactor = 1.0;
    double imSum = this->_sum;
    if (doNormalize) {
        if (imSum == 0) {
            throw LSST_EXCEPT(pexExcept::OverflowError, "Cannot normalize; kernel sum is 0");
        }
        multFactor = 1.0 / static_cast<double>(this->_sum);
        imSum = 1.0;
    }
 
    using XIter = image::Image<Pixel>::x_iterator;
 
    for (int y = 0; y != this->getHeight(); ++y) {
        for (XIter imPtr = image.row_begin(y), imEnd = image.row_end(y), kPtr = this->_image.row_begin(y);
             imPtr != imEnd; ++imPtr, ++kPtr) {
            imPtr[0] = multFactor * kPtr[0];
        }
    }
 
    return imSum;
}

dynamicCast() [1/2]

template std::shared_ptr< meas::extensions::psfex::PsfexPsf > lsst::afw::table::io::PersistableFacade< Kernel >::dynamicCast ( std::shared_ptr< Persistable > const & ptr )

staticinherited

Dynamically cast a shared_ptr.

Dynamically cast a shared pointer and raise on failure.

You must provide an explicit template instantiation in the .cc file for each class that inherits from PersistableFacade. Designed to work around RTTI issues on macOS with hidden symbols;

Exceptions

lsst::pex::exceptions::LogicError

if the cast fails

param[in] ptr The pointer to be cast.

Returns

The cast pointer.

Exceptions

lsst::pex::exceptions::TypeError

If the dynamic cast fails.

Definition at line 218 of file Persistable.cc.

dynamicCast() [2/2]

template std::shared_ptr< meas::extensions::psfex::PsfexPsf > lsst::afw::table::io::PersistableFacade< FixedKernel >::dynamicCast ( std::shared_ptr< Persistable > const & ptr )

staticinherited

Dynamically cast a shared_ptr.

Dynamically cast a shared pointer and raise on failure.

You must provide an explicit template instantiation in the .cc file for each class that inherits from PersistableFacade. Designed to work around RTTI issues on macOS with hidden symbols;

Exceptions

lsst::pex::exceptions::LogicError

if the cast fails

param[in] ptr The pointer to be cast.

Returns

The cast pointer.

Exceptions

lsst::pex::exceptions::TypeError

If the dynamic cast fails.

Definition at line 218 of file Persistable.cc.

getBBox()

lsst::geom::Box2I lsst::afw::math::Kernel::getBBox ( ) const

inlineinherited

return parent bounding box, with XY0 = -center

Definition at line 239 of file Kernel.h.

                                         {
        return lsst::geom::Box2I(lsst::geom::Point2I(-_ctrX, -_ctrY), lsst::geom::Extent2I(_width, _height));
    }

getCacheSize()

virtual int lsst::afw::math::Kernel::getCacheSize ( ) const

inlinevirtualinherited

Get the current size of the kernel cache (0 if none or if caches not supported)

Reimplemented in lsst::afw::math::SeparableKernel.

Definition at line 403 of file Kernel.h.

{ return 0; };

getCtr()

lsst::geom::Point2I lsst::afw::math::Kernel::getCtr ( ) const

inlineinherited

Return index of kernel's center.

Definition at line 234 of file Kernel.h.

{ return lsst::geom::Point2I(_ctrX, _ctrY); }

getDimensions()

lsst::geom::Extent2I const lsst::afw::math::Kernel::getDimensions ( ) const

inlineinherited

Return the Kernel's dimensions (width, height)

Definition at line 212 of file Kernel.h.

{ return lsst::geom::Extent2I(_width, _height); }

getHeight()

int lsst::afw::math::Kernel::getHeight ( ) const

inlineinherited

Return the Kernel's height.

Definition at line 229 of file Kernel.h.

{ return _height; }

getKernelParameter()

virtual double lsst::afw::math::Kernel::getKernelParameter ( unsigned int i ) const

inlinevirtualinherited

Return a particular Kernel Parameter (no bounds checking).

This version is slow, but specialisations may be faster

Reimplemented in lsst::afw::math::SeparableKernel.

Definition at line 277 of file Kernel.h.

{ return getKernelParameters()[i]; }

getKernelParameters()

std::vector< double > lsst::afw::math::Kernel::getKernelParameters ( ) const

virtualinherited

Return the current kernel parameters.

If the kernel is spatially varying then the parameters are those last computed. See also computeKernelParametersFromSpatialModel. If there are no kernel parameters then returns an empty vector.

Reimplemented in lsst::afw::math::AnalyticKernel, lsst::afw::math::LinearCombinationKernel, and lsst::afw::math::SeparableKernel.

Definition at line 165 of file Kernel.cc.

{ return std::vector<double>(); }

getNKernelParameters()

unsigned int lsst::afw::math::Kernel::getNKernelParameters ( ) const

inlineinherited

Return the number of kernel parameters (0 if none)

Definition at line 246 of file Kernel.h.

{ return _nKernelParams; }

getNSpatialParameters()

int lsst::afw::math::Kernel::getNSpatialParameters ( ) const

inlineinherited

Return the number of spatial parameters (0 if not spatially varying)

Definition at line 251 of file Kernel.h.

                                             {
        return this->isSpatiallyVarying() ? _spatialFunctionList[0]->getNParameters() : 0;
    }

getPersistenceName()

std::string lsst::afw::math::FixedKernel::getPersistenceName ( ) const

overrideprotectedvirtual

Return the unique name used to persist this object and look up its factory.

Must be less than ArchiveIndexSchema::MAX_NAME_LENGTH characters.

Reimplemented from lsst::afw::table::io::Persistable.

Definition at line 180 of file FixedKernel.cc.

{ return getFixedKernelPersistenceName(); }

getPythonModule()

std::string lsst::afw::math::Kernel::getPythonModule ( ) const

overrideprotectedvirtualinherited

Return the fully-qualified Python module that should be imported to guarantee that its factory is registered.

Must be less than ArchiveIndexSchema::MAX_MODULE_LENGTH characters.

Will be ignored if empty.

Reimplemented from lsst::afw::table::io::Persistable.

Reimplemented in lsst::afw::math::LanczosWarpingKernel, and lsst::afw::math::NearestWarpingKernel.

Definition at line 224 of file Kernel.cc.

{ return "lsst.afw.math"; }

getSpatialFunction()

Kernel::SpatialFunctionPtr lsst::afw::math::Kernel::getSpatialFunction ( unsigned int index ) const

inherited

Return a clone of the specified spatial function (one component of the spatial model)

Parameters

index

index of desired spatial function; must be in range [0, number spatial parameters - 1]

Returns

a shared pointer to a spatial function. The function is a deep copy, so setting its parameters has no effect on the kernel.

Exceptions

lsst::pex::exceptions::InvalidParameterError	if kernel not spatially varying
lsst::pex::exceptions::InvalidParameterError	if index out of range

Definition at line 144 of file Kernel.cc.

                                                                            {
    if (index >= _spatialFunctionList.size()) {
        if (!this->isSpatiallyVarying()) {
            throw LSST_EXCEPT(pexExcept::InvalidParameterError, "kernel is not spatially varying");
        } else {
            std::ostringstream errStream;
            errStream << "index = " << index << "; must be < , " << _spatialFunctionList.size();
            throw LSST_EXCEPT(pexExcept::InvalidParameterError, errStream.str());
        }
    }
    return _spatialFunctionList[index]->clone();
}

getSpatialFunctionList()

std::vector< Kernel::SpatialFunctionPtr > lsst::afw::math::Kernel::getSpatialFunctionList ( ) const

inherited

Return a list of clones of the spatial functions.

Returns

a list of shared pointers to spatial functions. The functions are deep copies, so setting their parameters has no effect on the kernel.

Definition at line 157 of file Kernel.cc.

                                                                         {
    std::vector<SpatialFunctionPtr> spFuncCopyList;
    for (auto const &spFuncIter : _spatialFunctionList) {
        spFuncCopyList.push_back((*spFuncIter).clone());
    }
    return spFuncCopyList;
}

getSpatialParameters()

std::vector< std::vector< double > > lsst::afw::math::Kernel::getSpatialParameters ( ) const

inlineinherited

Return the spatial parameters parameters (an empty vector if not spatially varying)

Definition at line 321 of file Kernel.h.

                                                                     {
        std::vector<std::vector<double>> spatialParams;
        std::vector<SpatialFunctionPtr>::const_iterator spFuncIter = _spatialFunctionList.begin();
        for (; spFuncIter != _spatialFunctionList.end(); ++spFuncIter) {
            spatialParams.push_back((*spFuncIter)->getParameters());
        }
        return spatialParams;
    }

getSum()

virtual Pixel lsst::afw::math::FixedKernel::getSum ( ) const

inlinevirtual

Definition at line 504 of file Kernel.h.

{ return _sum; }

getWidth()

int lsst::afw::math::Kernel::getWidth ( ) const

inlineinherited

Return the Kernel's width.

Definition at line 224 of file Kernel.h.

{ return _width; }

growBBox()

lsst::geom::Box2I lsst::afw::math::Kernel::growBBox ( lsst::geom::Box2I const & bbox ) const

inherited

Given a bounding box for pixels one wishes to compute by convolving an image with this kernel, return the bounding box of pixels that must be accessed on the image to be convolved.

Thus the box shifted by -kernel.getCtr() and its size is expanded by kernel.getDimensions()-1.

Returns

the bbox expanded by the kernel.

Definition at line 167 of file Kernel.cc.

                                                              {
    return lsst::geom::Box2I(
            lsst::geom::Point2I(bbox.getMin() - lsst::geom::Extent2I(getCtr())),
            lsst::geom::Extent2I(bbox.getDimensions() + getDimensions() - lsst::geom::Extent2I(1, 1)));
}

isPersistable()

bool lsst::afw::math::FixedKernel::isPersistable ( ) const

inlineoverridevirtualnoexcept

Return true if this particular object can be persisted using afw::table::io.

Reimplemented from lsst::afw::table::io::Persistable.

Definition at line 506 of file Kernel.h.

{ return true; }

isSpatiallyVarying()

bool lsst::afw::math::Kernel::isSpatiallyVarying ( ) const

inlineinherited

Return true iff the kernel is spatially varying (has a spatial function)

Definition at line 333 of file Kernel.h.

{ return _spatialFunctionList.size() != 0; }

operator=() [1/2]

FixedKernel & lsst::afw::math::FixedKernel::operator= ( const FixedKernel & )

delete

operator=() [2/2]

FixedKernel & lsst::afw::math::FixedKernel::operator= ( FixedKernel && )

delete

readFits() [1/6]

static std::shared_ptr< Kernel > lsst::afw::table::io::PersistableFacade< Kernel >::readFits ( fits::Fits & fitsfile )

inlinestaticinherited

Read an object from an already open FITS object.

Parameters

[in]

fitsfile

FITS object to read from, already positioned at the desired HDU.

Definition at line 183 of file Persistable.h.

readFits() [2/6]

static std::shared_ptr< FixedKernel > lsst::afw::table::io::PersistableFacade< FixedKernel >::readFits ( fits::Fits & fitsfile )

inlinestaticinherited

Read an object from an already open FITS object.

Parameters

[in]

fitsfile

FITS object to read from, already positioned at the desired HDU.

Definition at line 183 of file Persistable.h.

readFits() [3/6]

static std::shared_ptr< Kernel > lsst::afw::table::io::PersistableFacade< Kernel >::readFits ( fits::MemFileManager & manager, int hdu = fits::DEFAULT_HDU )

inlinestaticinherited

Read an object from a FITS file in memory.

Parameters

[in]	manager	Manager for the memory to read from.
[in]	hdu	HDU to read, where 0 is the primary. The special value of afw::fits::DEFAULT_HDU skips the primary HDU if it is empty.

Definition at line 205 of file Persistable.h.

readFits() [4/6]

static std::shared_ptr< FixedKernel > lsst::afw::table::io::PersistableFacade< FixedKernel >::readFits ( fits::MemFileManager & manager, int hdu = fits::DEFAULT_HDU )

inlinestaticinherited

Read an object from a FITS file in memory.

Parameters

[in]	manager	Manager for the memory to read from.
[in]	hdu	HDU to read, where 0 is the primary. The special value of afw::fits::DEFAULT_HDU skips the primary HDU if it is empty.

Definition at line 205 of file Persistable.h.

readFits() [5/6]

static std::shared_ptr< Kernel > lsst::afw::table::io::PersistableFacade< Kernel >::readFits ( std::string const & fileName, int hdu = fits::DEFAULT_HDU )

inlinestaticinherited

Read an object from a regular FITS file.

Parameters

[in]	fileName	Name of the file to read.
[in]	hdu	HDU to read, where 0 is the primary. The special value of afw::fits::DEFAULT_HDU skips the primary HDU if it is empty.

Definition at line 194 of file Persistable.h.

readFits() [6/6]

static std::shared_ptr< FixedKernel > lsst::afw::table::io::PersistableFacade< FixedKernel >::readFits ( std::string const & fileName, int hdu = fits::DEFAULT_HDU )

inlinestaticinherited

Read an object from a regular FITS file.

Parameters

[in]	fileName	Name of the file to read.
[in]	hdu	HDU to read, where 0 is the primary. The special value of afw::fits::DEFAULT_HDU skips the primary HDU if it is empty.

Definition at line 194 of file Persistable.h.

resized()

std::shared_ptr< Kernel > lsst::afw::math::FixedKernel::resized ( int width, int height ) const

overridevirtual

Return a pointer to a clone with specified kernel dimensions.

Parameters

width	Number of columns in pixels
height	Number of rows in pixels

Returns

a pointer to a clone with new dimensions.

Must be implemented by derived classes.

Implements lsst::afw::math::Kernel.

Definition at line 68 of file FixedKernel.cc.

                                                                      {
    if ((width <= 0) || (height <= 0)) {
        std::ostringstream os;
        os << "Cannot create FixedKernel with dimensions (" << width << ", " << height << "). ";
        throw LSST_EXCEPT(pexExcept::InvalidParameterError, os.str());
    }
    if ((width - getWidth()) % 2 || (height - getHeight()) % 2) {
        std::ostringstream os;
        os << "Cannot resize FixedKernel from (" << getWidth() << ", " << getHeight() << ") to (" << width
           << ", " << height << "), because at least one dimension would change by an odd value.";
        throw LSST_EXCEPT(pexExcept::InvalidParameterError, os.str());
    }
 
    lsst::geom::Box2I bboxNew(lsst::geom::Point2I((1 - width) / 2, (1 - height) / 2),
                              lsst::geom::Extent2I(width, height));
    std::shared_ptr<image::Image<Pixel>> imNew = std::make_shared<image::Image<Pixel>>(bboxNew);
 
    // getBBox() instantiates a new BBox from member data _width, _height, _ctrX, _ctrY
    // so modifying it is OK
    lsst::geom::Box2I bboxIntersect = getBBox();
    bboxIntersect.clip(bboxNew);
 
    // Kernel (this) and member image (this->_image) do not always have same XY0.
    // Member image of resized kernel will not have same BBox as orig,
    // but BBox of member image is ignored by the kernel.
    int offsetX = _image.getX0() - getBBox().getMinX();
    int offsetY = _image.getY0() - getBBox().getMinY();
    lsst::geom::Box2I bboxIntersectShifted = lsst::geom::Box2I(
            lsst::geom::Point2I(bboxIntersect.getMinX() + offsetX, bboxIntersect.getMinY() + offsetY),
            bboxIntersect.getDimensions());
    image::Image<Pixel> imIntersect = image::Image<Pixel>(_image, bboxIntersectShifted);
 
    imNew->assign(imIntersect, bboxIntersect);
    std::shared_ptr<Kernel> retPtr = std::make_shared<FixedKernel>(*imNew);
    return retPtr;
}

setCtr()

void lsst::afw::math::Kernel::setCtr ( lsst::geom::Point2I ctr )

inlineinherited

Set index of kernel's center.

Definition at line 312 of file Kernel.h.

                                            {
        _ctrX = ctr.getX();
        _ctrY = ctr.getY();
        _setKernelXY();
    }

setDimensions()

void lsst::afw::math::Kernel::setDimensions ( lsst::geom::Extent2I dims )

inlineinherited

Definition at line 214 of file Kernel.h.

                                              {
        _width = dims.getX();
        _height = dims.getY();
    }

setHeight()

void lsst::afw::math::Kernel::setHeight ( int height )

inlineinherited

Definition at line 219 of file Kernel.h.

{ _height = height; }

setKernelParameter()

void lsst::afw::math::Kernel::setKernelParameter ( unsigned int ind, double value ) const

protectedvirtualinherited

Set one kernel parameter.

Classes that have kernel parameters must subclass this function.

This function is marked "const", despite modifying unimportant internals, so that computeImage can be const.

Exceptions

lsst::pex::exceptions::InvalidParameterError

always (unless subclassed)

Reimplemented in lsst::afw::math::AnalyticKernel, lsst::afw::math::LinearCombinationKernel, lsst::afw::math::SeparableKernel, lsst::afw::math::LanczosWarpingKernel, lsst::afw::math::BilinearWarpingKernel, and lsst::afw::math::NearestWarpingKernel.

Definition at line 213 of file Kernel.cc.

                                                          {
    throw LSST_EXCEPT(pexExcept::InvalidParameterError, "Kernel has no kernel parameters");
}

setKernelParameters() [1/2]

void lsst::afw::math::Kernel::setKernelParameters ( std::pair< double, double > const & params )

inlineinherited

Set the kernel parameters of a 2-component spatially invariant kernel.

Warning

This is a low-level method intended for maximum efficiency when using warping kernels. No error checking is performed. Use the std::vector<double> form if you want safety.

Definition at line 363 of file Kernel.h.

                                                                           {
        this->setKernelParameter(0, params.first);
        this->setKernelParameter(1, params.second);
    }

setKernelParameters() [2/2]

void lsst::afw::math::Kernel::setKernelParameters ( std::vector< double > const & params )

inlineinherited

Set the kernel parameters of a spatially invariant kernel.

Exceptions

lsst::pex::exceptions::RuntimeError	if the kernel has a spatial function
lsst::pex::exceptions::InvalidParameterError	if the params vector is the wrong length

Definition at line 341 of file Kernel.h.

                                                                     {
        if (this->isSpatiallyVarying()) {
            throw LSST_EXCEPT(lsst::pex::exceptions::RuntimeError, "Kernel is spatially varying");
        }
        const unsigned int nParams = this->getNKernelParameters();
        if (nParams != params.size()) {
            throw LSST_EXCEPT(lsst::pex::exceptions::InvalidParameterError,
                              (boost::format("Number of parameters is wrong, saw %d expected %d") % nParams %
                               params.size())
                                      .str());
        }
        for (unsigned int ii = 0; ii < nParams; ++ii) {
            this->setKernelParameter(ii, params[ii]);
        }
    }

setKernelParametersFromSpatialModel()

void lsst::afw::math::Kernel::setKernelParametersFromSpatialModel ( double x, double y ) const

protectedinherited

Set the kernel parameters from the spatial model (if any).

This function has no effect if there is no spatial model.

This function is marked "const", despite modifying unimportant internals, so that computeImage can be const.

Definition at line 217 of file Kernel.cc.

                                                                         {
    std::vector<SpatialFunctionPtr>::const_iterator funcIter = _spatialFunctionList.begin();
    for (int ii = 0; funcIter != _spatialFunctionList.end(); ++funcIter, ++ii) {
        this->setKernelParameter(ii, (*(*funcIter))(x, y));
    }
}

setSpatialParameters()

void lsst::afw::math::Kernel::setSpatialParameters ( const std::vector< std::vector< double > > params )

inherited

Set the parameters of all spatial functions.

Params is indexed as [kernel parameter][spatial parameter]

Exceptions

lsst::pex::exceptions::InvalidParameterError

if params is the wrong shape (if this exception is thrown then no parameters are changed)

Definition at line 110 of file Kernel.cc.

                                                                            {
    // Check params size before changing anything
    unsigned int nKernelParams = this->getNKernelParameters();
    if (params.size() != nKernelParams) {
        throw LSST_EXCEPT(
                pexExcept::InvalidParameterError,
                (boost::format("params has %d entries instead of %d") % params.size() % nKernelParams).str());
    }
    unsigned int nSpatialParams = this->getNSpatialParameters();
    for (unsigned int ii = 0; ii < nKernelParams; ++ii) {
        if (params[ii].size() != nSpatialParams) {
            throw LSST_EXCEPT(pexExcept::InvalidParameterError,
                              (boost::format("params[%d] has %d entries instead of %d") % ii %
                               params[ii].size() % nSpatialParams)
                                      .str());
        }
    }
    // Set parameters
    if (nSpatialParams > 0) {
        for (unsigned int ii = 0; ii < nKernelParams; ++ii) {
            this->_spatialFunctionList[ii]->setParameters(params[ii]);
        }
    }
}

setWidth()

void lsst::afw::math::Kernel::setWidth ( int width )

inlineinherited

Definition at line 218 of file Kernel.h.

{ _width = width; }

shrinkBBox()

lsst::geom::Box2I lsst::afw::math::Kernel::shrinkBBox ( lsst::geom::Box2I const & bbox ) const

inherited

Given a bounding box for an image one wishes to convolve with this kernel, return the bounding box for the region of pixels that can be computed.

Thus the box shifted by kernel.getCtr() and its size is reduced by kernel.getDimensions()-1.

Returns

the bbox shrunk by the kernel.

Exceptions

lsst::pex::exceptions::InvalidParameterError

if the resulting box would have dimension < 1 in either axis

Definition at line 173 of file Kernel.cc.

                                                                {
    if ((bbox.getWidth() < getWidth()) || ((bbox.getHeight() < getHeight()))) {
        std::ostringstream os;
        os << "bbox dimensions = " << bbox.getDimensions() << " < (" << getWidth() << ", " << getHeight()
           << ") in one or both dimensions";
        throw LSST_EXCEPT(pexExcept::InvalidParameterError, os.str());
    }
    return lsst::geom::Box2I(
            lsst::geom::Point2I(bbox.getMin() + lsst::geom::Extent2I(getCtr())),
            lsst::geom::Extent2I(bbox.getWidth() + 1 - getWidth(), bbox.getHeight() + 1 - getHeight()));
}

toString()

std::string lsst::afw::math::FixedKernel::toString ( std::string const & prefix = "" ) const

overridevirtual

Return a string representation of the kernel.

Reimplemented from lsst::afw::math::Kernel.

Definition at line 128 of file FixedKernel.cc.

                                                             {
    std::ostringstream os;
    os << prefix << "FixedKernel:" << std::endl;
    os << prefix << "..sum: " << _sum << std::endl;
    os << Kernel::toString(prefix + "\t");
    return os.str();
}

write()

void lsst::afw::math::FixedKernel::write ( OutputArchiveHandle & handle ) const

overrideprotectedvirtual

Write the object to one or more catalogs.

The handle object passed to this function provides an interface for adding new catalogs and adding nested objects to the same archive (while checking for duplicates). See OutputArchiveHandle for more information.

Reimplemented from lsst::afw::table::io::Persistable.

Definition at line 182 of file FixedKernel.cc.

                                                         {
    FixedKernelPersistenceHelper const keys(getDimensions());
    std::shared_ptr<afw::table::BaseRecord> record = keys.write(handle, *this);
    (*record)[keys.image] = ndarray::flatten<1>(ndarray::copy(_image.getArray()));
}

writeFits() [1/3]

void lsst::afw::table::io::Persistable::writeFits ( fits::Fits & fitsfile ) const

inherited

Write the object to an already-open FITS object.

Parameters

[in]

fitsfile

Open FITS object to write to.

Definition at line 18 of file Persistable.cc.

                                                    {
    OutputArchive archive;
    archive.put(this);
    archive.writeFits(fitsfile);
}

writeFits() [2/3]

void lsst::afw::table::io::Persistable::writeFits ( fits::MemFileManager & manager, std::string const & mode = "w" ) const

inherited

Write the object to a FITS image in memory.

Parameters

[in]	manager	Name of the file to write to.
[in]	mode	If "w", any existing file with the given name will be overwritten. If "a", new HDUs will be appended to an existing file.

Definition at line 29 of file Persistable.cc.

                                                                                    {
    fits::Fits fitsfile(manager, mode, fits::Fits::AUTO_CLOSE | fits::Fits::AUTO_CHECK);
    writeFits(fitsfile);
}

writeFits() [3/3]

void lsst::afw::table::io::Persistable::writeFits ( std::string const & fileName, std::string const & mode = "w" ) const

inherited

Write the object to a regular FITS file.

Parameters

[in]	fileName	Name of the file to write to.
[in]	mode	If "w", any existing file with the given name will be overwritten. If "a", new HDUs will be appended to an existing file.

Definition at line 24 of file Persistable.cc.

                                                                                  {
    fits::Fits fitsfile(fileName, mode, fits::Fits::AUTO_CLOSE | fits::Fits::AUTO_CHECK);
    writeFits(fitsfile);
}

Member Data Documentation

_spatialFunctionList

std::vector<SpatialFunctionPtr> lsst::afw::math::Kernel::_spatialFunctionList

protectedinherited

Definition at line 449 of file Kernel.h.

---

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/afw/g9726552aa6+10f999ec6a/include/lsst/afw/math/Kernel.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/afw/g9726552aa6+10f999ec6a/src/math/FixedKernel.cc