lsst::afw::math::DoubleGaussianFunction2< ReturnT > Class Template Reference

double Guassian (sum of two Gaussians) More...

#include <FunctionLibrary.h>

Inheritance diagram for lsst::afw::math::DoubleGaussianFunction2< ReturnT >:

Public Member Functions
	DoubleGaussianFunction2 (double sigma1, double sigma2=0, double ampl2=0)
	Construct a Gaussian function with specified x and y sigma.
	DoubleGaussianFunction2 (DoubleGaussianFunction2 const &)=default
	DoubleGaussianFunction2 (DoubleGaussianFunction2 &&)=default
DoubleGaussianFunction2 &	operator= (DoubleGaussianFunction2 const &)=default
DoubleGaussianFunction2 &	operator= (DoubleGaussianFunction2 &&)=default
	~DoubleGaussianFunction2 () noexcept override=default
std::shared_ptr< Function2< ReturnT > >	clone () const override
	Return a pointer to a deep copy of this function.
ReturnT	operator() (double x, double y) const noexcept(IS_NOTHROW_INIT< ReturnT >) override
std::string	toString (std::string const &prefix) const override
	Return a string representation of the function.
bool	isPersistable () const noexcept override
	Return true if this particular object can be persisted using afw::table::io.
virtual std::vector< double >	getDFuncDParameters (double, double) const
	Return the derivative of the Function with respect to its parameters.
unsigned int	getNParameters () const noexcept
	Return the number of function parameters.
virtual double	getParameter (unsigned int ind) const
	Get one function parameter without range checking.
std::vector< double > const &	getParameters () const noexcept
	Return all function parameters.
virtual bool	isLinearCombination () const noexcept
	Is the function a linear combination of its parameters?
void	setParameter (unsigned int ind, double newValue)
	Set one function parameter without range checking.
void	setParameters (std::vector< double > const &params)
	Set all function parameters.
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< Function2< ReturnT > >	readFits (fits::Fits &fitsfile)
	Read an object from an already open FITS object.
static std::shared_ptr< Function2< ReturnT > >	readFits (std::string const &fileName, int hdu=fits::DEFAULT_HDU)
	Read an object from a regular FITS file.
static std::shared_ptr< Function2< ReturnT > >	readFits (fits::MemFileManager &manager, int hdu=fits::DEFAULT_HDU)
	Read an object from a FITS file in memory.
static std::shared_ptr< Function< ReturnT > >	readFits (fits::Fits &fitsfile)
	Read an object from an already open FITS object.
static std::shared_ptr< Function< ReturnT > >	readFits (std::string const &fileName, int hdu=fits::DEFAULT_HDU)
	Read an object from a regular FITS file.
static std::shared_ptr< Function< ReturnT > >	readFits (fits::MemFileManager &manager, int hdu=fits::DEFAULT_HDU)
	Read an object from a FITS file in memory.
static std::shared_ptr< Function2< ReturnT > >	dynamicCast (std::shared_ptr< Persistable > const &ptr)
	Dynamically cast a shared_ptr.
static std::shared_ptr< Function< ReturnT > >	dynamicCast (std::shared_ptr< Persistable > const &ptr)
	Dynamically cast a shared_ptr.

Protected Types
using	OutputArchiveHandle = io::OutputArchiveHandle

Protected Member Functions
std::string	getPersistenceName () const override
	Return the unique name used to persist this object and look up its factory.
void	write (afw::table::io::OutputArchiveHandle &handle) const override
	Write the object to one or more catalogs.
	DoubleGaussianFunction2 ()
std::string	getPythonModule () const override
	Return the fully-qualified Python module that should be imported to guarantee that its factory is registered.

Protected Attributes
std::vector< double >	_params
bool	_isCacheValid

Detailed Description

template<typename ReturnT>
class lsst::afw::math::DoubleGaussianFunction2< ReturnT >

double Guassian (sum of two Gaussians)

Intended for use as a PSF model: the main Gaussian represents the core and the second Gaussian represents the wings.

f(x,y) = A (e^(-r^2 / 2 sigma1^2) + ampl2 e^(-r^2 / 2 sigma2^2)) where:

• A = 1 / (2 pi (sigma1^2 + ampl2 sigma2^2))
• r^2 = x^2 + y^2 coefficients c[0] = sigma1, c[1] = sigma2, c[2] = ampl2

Definition at line 303 of file FunctionLibrary.h.

Member Typedef Documentation

OutputArchiveHandle

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

protectedinherited

Definition at line 108 of file Persistable.h.

Constructor & Destructor Documentation

DoubleGaussianFunction2() [1/4]

template<typename ReturnT >

lsst::afw::math::DoubleGaussianFunction2< ReturnT >::DoubleGaussianFunction2 ( double sigma1, double sigma2 = 0, double ampl2 = 0 )

inlineexplicit

Construct a Gaussian function with specified x and y sigma.

Parameters

sigma1	sigma of main Gaussian
sigma2	sigma of second Gaussian
ampl2	amplitude of second Gaussian as a fraction of main Gaussian at peak

Definition at line 308 of file FunctionLibrary.h.

            : Function2<ReturnT>(3), _multFac(1.0 / (lsst::geom::TWOPI)) {
        this->_params[0] = sigma1;
        this->_params[1] = sigma2;
        this->_params[2] = ampl2;
    }

DoubleGaussianFunction2() [2/4]

template<typename ReturnT >

lsst::afw::math::DoubleGaussianFunction2< ReturnT >::DoubleGaussianFunction2 ( DoubleGaussianFunction2< ReturnT > const & )

default

DoubleGaussianFunction2() [3/4]

template<typename ReturnT >

lsst::afw::math::DoubleGaussianFunction2< ReturnT >::DoubleGaussianFunction2 ( DoubleGaussianFunction2< ReturnT > && )

default

~DoubleGaussianFunction2()

template<typename ReturnT >

lsst::afw::math::DoubleGaussianFunction2< ReturnT >::~DoubleGaussianFunction2 ( )

overridedefaultnoexcept

DoubleGaussianFunction2() [4/4]

template<typename ReturnT >

lsst::afw::math::DoubleGaussianFunction2< ReturnT >::DoubleGaussianFunction2 ( )

inlineexplicitprotected

Definition at line 358 of file FunctionLibrary.h.

: Function2<ReturnT>(3), _multFac(1.0 / (lsst::geom::TWOPI)) {}

Member Function Documentation

clone()

template<typename ReturnT >

std::shared_ptr< Function2< ReturnT > > lsst::afw::math::DoubleGaussianFunction2< ReturnT >::clone ( ) const

inlineoverridevirtual

Return a pointer to a deep copy of this function.

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

Every non-virtual function must override this method.

Returns

a pointer to a deep copy of the function

Implements lsst::afw::math::Function2< ReturnT >.

Definition at line 324 of file FunctionLibrary.h.

                                                             {
        return std::shared_ptr<Function2<ReturnT>>(
                new DoubleGaussianFunction2(this->_params[0], this->_params[1], this->_params[2]));
    }

dynamicCast() [1/2]

template std::shared_ptr< meas::extensions::psfex::PsfexPsf > lsst::afw::table::io::PersistableFacade< Function< ReturnT > >::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< Function2< ReturnT > >::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.

getDFuncDParameters()

template<typename ReturnT >

virtual std::vector< double > lsst::afw::math::Function2< ReturnT >::getDFuncDParameters ( double , double  ) const

inlinevirtualinherited

Return the derivative of the Function with respect to its parameters.

Reimplemented in lsst::afw::math::BasePolynomialFunction2< ReturnT >, and lsst::afw::math::PolynomialFunction2< ReturnT >.

Definition at line 305 of file Function.h.

                                                                        {
        throw LSST_EXCEPT(lsst::pex::exceptions::NotFoundError,
                          "getDFuncDParameters is not implemented for this class");
    }

getNParameters()

template<typename ReturnT >

unsigned int lsst::afw::math::Function< ReturnT >::getNParameters ( ) const

inlinenoexceptinherited

Return the number of function parameters.

Returns

the number of function parameters

Definition at line 112 of file Function.h.

{ return _params.size(); }

getParameter()

template<typename ReturnT >

virtual double lsst::afw::math::Function< ReturnT >::getParameter ( unsigned int ind ) const

inlinevirtualinherited

Get one function parameter without range checking.

Returns

the specified function parameter

Parameters

ind	index of parameter

Definition at line 119 of file Function.h.

                  {
        return _params[ind];
    }

getParameters()

template<typename ReturnT >

std::vector< double > const & lsst::afw::math::Function< ReturnT >::getParameters ( ) const

inlinenoexceptinherited

Return all function parameters.

Returns

the function parameters as a vector

Definition at line 129 of file Function.h.

{ return _params; }

getPersistenceName()

template<typename ReturnT >

std::string lsst::afw::math::DoubleGaussianFunction2< ReturnT >::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 202 of file FunctionLibrary.cc.

                                                                     {
    return "DoubleGaussianFunction2" + Suffix<ReturnT>::get();
}

getPythonModule()

template<typename ReturnT >

std::string lsst::afw::math::Function< ReturnT >::getPythonModule ( ) const

inlineoverrideprotectedvirtualinherited

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.

Definition at line 188 of file Function.h.

{ return "lsst.afw.math"; }

isLinearCombination()

template<typename ReturnT >

virtual bool lsst::afw::math::Function< ReturnT >::isLinearCombination ( ) const

inlinevirtualnoexceptinherited

Is the function a linear combination of its parameters?

Returns

true if the function can be expressed as: sum over i of parameter_i * function_i(args)

Warning

: subclasses must override if true.

Reimplemented in lsst::afw::math::BasePolynomialFunction2< ReturnT >, lsst::afw::math::PolynomialFunction1< ReturnT >, and lsst::afw::math::Chebyshev1Function1< ReturnT >.

Definition at line 138 of file Function.h.

{ return false; }

isPersistable()

template<typename ReturnT >

bool lsst::afw::math::DoubleGaussianFunction2< ReturnT >::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 346 of file FunctionLibrary.h.

{ return true; }

operator()()

template<typename ReturnT >

ReturnT lsst::afw::math::DoubleGaussianFunction2< ReturnT >::operator() ( double x, double y ) const

inlineoverridevirtualnoexcept

Implements lsst::afw::math::Function2< ReturnT >.

Definition at line 329 of file FunctionLibrary.h.

                                                                                             {
        double radSq = (x * x) + (y * y);
        double sigma1Sq = this->_params[0] * this->_params[0];
        double sigma2Sq = this->_params[1] * this->_params[1];
        double b = this->_params[2];
        return static_cast<ReturnT>(
                (_multFac / (sigma1Sq + (b * sigma2Sq))) *
                (std::exp(-radSq / (2.0 * sigma1Sq)) + (b * std::exp(-radSq / (2.0 * sigma2Sq)))));
    }

operator=() [1/2]

template<typename ReturnT >

DoubleGaussianFunction2 & lsst::afw::math::DoubleGaussianFunction2< ReturnT >::operator= ( DoubleGaussianFunction2< ReturnT > && )

default

operator=() [2/2]

template<typename ReturnT >

DoubleGaussianFunction2 & lsst::afw::math::DoubleGaussianFunction2< ReturnT >::operator= ( DoubleGaussianFunction2< ReturnT > const & )

default

readFits() [1/6]

static std::shared_ptr< Function< ReturnT > > lsst::afw::table::io::PersistableFacade< Function< ReturnT > >::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< Function2< ReturnT > > lsst::afw::table::io::PersistableFacade< Function2< ReturnT > >::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< Function< ReturnT > > lsst::afw::table::io::PersistableFacade< Function< ReturnT > >::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< Function2< ReturnT > > lsst::afw::table::io::PersistableFacade< Function2< ReturnT > >::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< Function< ReturnT > > lsst::afw::table::io::PersistableFacade< Function< ReturnT > >::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< Function2< ReturnT > > lsst::afw::table::io::PersistableFacade< Function2< ReturnT > >::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.

setParameter()

template<typename ReturnT >

void lsst::afw::math::Function< ReturnT >::setParameter ( unsigned int ind, double newValue )

inlineinherited

Set one function parameter without range checking.

Parameters

ind	index of parameter
newValue	new value for parameter

Definition at line 143 of file Function.h.

    {
        _isCacheValid = false;
        _params[ind] = newValue;
    }

setParameters()

template<typename ReturnT >

void lsst::afw::math::Function< ReturnT >::setParameters ( std::vector< double > const & params )

inlineinherited

Set all function parameters.

Exceptions

lsst::pex::exceptions::InvalidParameterError

if the wrong number of parameters is supplied.

Parameters

params

vector of function parameters

Definition at line 156 of file Function.h.

    {
        if (_params.size() != params.size()) {
            throw LSST_EXCEPT(
                    pexExcept::InvalidParameterError,
                    (boost::format("params has %d entries instead of %d") % params.size() % _params.size())
                            .str());
        }
        _isCacheValid = false;
        _params = params;
    }

toString()

template<typename ReturnT >

std::string lsst::afw::math::DoubleGaussianFunction2< ReturnT >::toString ( std::string const & ) const

inlineoverridevirtual

Return a string representation of the function.

Returns

a string representation of the function

Reimplemented from lsst::afw::math::Function< ReturnT >.

Definition at line 339 of file FunctionLibrary.h.

                                                               {
        std::ostringstream os;
        os << "DoubleGaussianFunction2 [" << _multFac << "]: ";
        os << Function2<ReturnT>::toString(prefix);
        return os.str();
    }

write()

template<typename ReturnT >

void lsst::afw::math::DoubleGaussianFunction2< ReturnT >::write ( afw::table::io::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 228 of file FunctionLibrary.cc.

                                                                                     {
    DoubleGaussianFunction2PersistenceHelper const& keys = DoubleGaussianFunction2PersistenceHelper::get();
    table::BaseCatalog catalog = handle.makeCatalog(keys.schema);
    std::shared_ptr<table::BaseRecord> record = catalog.addNew();
    record->set(keys.sigma1, this->getParameters()[0]);
    record->set(keys.sigma2, this->getParameters()[1]);
    record->set(keys.ampl2, this->getParameters()[2]);
    handle.saveCatalog(catalog);
}

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

_isCacheValid

template<typename ReturnT >

bool lsst::afw::math::Function< ReturnT >::_isCacheValid

mutableprotectedinherited

Definition at line 186 of file Function.h.

_params

template<typename ReturnT >

std::vector<double> lsst::afw::math::Function< ReturnT >::_params

protectedinherited

Definition at line 185 of file Function.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/FunctionLibrary.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/afw/g9726552aa6+10f999ec6a/src/math/FunctionLibrary.cc