lsst::gauss2d::Ellipse Class Reference

An Ellipse with sigma_x, sigma_y, and rho values. More...

#include <ellipse.h>

Inheritance diagram for lsst::gauss2d::Ellipse:

Public Member Functions
	Ellipse (std::shared_ptr< EllipseData > data)
	Ellipse (double sigma_x=0, double sigma_y=0, double rho=0)
	Construct a new Ellipse object with default float values.
	Ellipse (const Covariance &covar)
	Ellipse (const EllipseMajor &ellipse)
const EllipseData &	get_data () const
	Return a const ref to this ellipse's data.
double	get_rho () const override
	Get rho.
double	get_sigma_x () const override
	Get sigma_x.
double	get_sigma_y () const override
	Get sigma_y.
std::shared_ptr< Ellipse >	make_convolution (const Ellipse &ell) const
	Return the convolution of this with another ellipse.
std::unique_ptr< Ellipse >	make_convolution_uniq (const Ellipse &ell) const
	Same as make_convolution(), but returning a unique_ptr.
void	set_rho (double rho) override
	Set the correlation parameter (rho)
void	set_sigma_x (double sigma_x) override
	Set the x-axis dispersion (sigma)
void	set_sigma_y (double sigma_y) override
	Set the y-axis dispersion (sigma)
std::string	repr (bool name_keywords=false, std::string_view namespace_separator=Object::CC_NAMESPACE_SEPARATOR) const override
	Return a full, callable string representation of this.
std::string	str () const override
	Return a brief, human-readable string representation of this.
bool	operator== (const Ellipse &other) const
bool	operator!= (const Ellipse &other) const
virtual void	convolve (const Ellipse &ell)
	Convolve this ellipse with another.
virtual double	get_area () const
	Return the area of this ellipse, equal to pi*sigma_major*sigma_minor.
virtual double	get_cov_xy () const
	Return the covariance, equal to sigma_x*sigma_y*rho.
virtual double	get_hwhm_x () const
	Get the x-axis half-width at half-maximum.
virtual double	get_hwhm_y () const
	Get the y-axis half-width at half-maximum.
virtual double	get_radius_trace () const
	Return the trace radius, equal to sqrt(sigma_x^2 + sigma_y^2)
virtual double	get_sigma_x_sq () const
	Get the square of sigma_x.
virtual double	get_sigma_y_sq () const
	Get the square of sigma_y.
virtual double	get_sigma_xy () const
	Return sigma_x*sigma_y.
virtual std::array< double, 3 >	get_hxyr () const
	Get hwhm_x, hwhm_y, rho.
virtual std::array< double, 3 >	get_xyr () const
	Get sigma_x, sigma_y, rho.
virtual void	set (double sigma_x, double sigma_y, double rho)
	Set sigma_x, sigma_y, rho.
virtual void	set (const Covariance &covar)
	Set values from a Covariance object.
virtual void	set (const EllipseMajor &ellipse)
	Set values from an EllipseMajor object.
virtual void	set_h (double hwhm_x, double hwhm_y, double rho)
	Set hwhm_x, hwhm_y, rho (half-width at half-max)
virtual void	set_hwhm_x (double hwhm_x)
	Set the x-axis half-width at half-max (FWHM/2)
virtual void	set_hwhm_y (double hwhm_y)
	Set the y-axis half-width at half-max (FWHM/2)
virtual void	set_hxyr (const std::array< double, 3 > &hxyr)
	Set hwhm_x, hwhm_y, rho from an array.
virtual void	set_xyr (const std::array< double, 3 > &xyr)
	Set sigma_x, sigma_y, rho from an array.
bool	operator== (const EllipseData &other) const
bool	operator!= (const EllipseData &other) const

Static Public Member Functions
static void	check (double size_x, double size_y, double rho, std::string_view error_suffix="")
	Check whether Ellipse parameter values are valid, throwing if not.
static void	check_size (double size, std::string_view error_suffix="")
	Check whether an x- or x-yaxis size value is valid.
static void	check_rho (double rho, std::string_view error_suffix="")
	Check whether a rho value is valid.
static std::string_view	null_str (const std::string_view &namespace_separator)

Static Public Attributes
static constexpr std::string_view	CC_NAMESPACE_SEPARATOR = "::"
	The C++ namespace separator.
static constexpr std::string_view	NULL_STR_GENERAL = "None"
static constexpr std::string_view	PY_NAMESPACE_SEPARATOR = "."

Detailed Description

An Ellipse with sigma_x, sigma_y, and rho values.

This ellipse parameterization requires sigma_x and sigma_y >=0, and the correlation -1 < rho < 1.

Note

This ellipse parameterization can be represented as a matrix, with sigma_x and sigma_y on the diagonal, and the other two values set to rho.

Definition at line 283 of file ellipse.h.

Constructor & Destructor Documentation

Ellipse() [1/4]

lsst::gauss2d::Ellipse::Ellipse ( std::shared_ptr< EllipseData > data )

explicit

Definition at line 232 of file ellipse.cc.

        : _data(data == nullptr ? std::make_shared<EllipseValues>() : std::move(data)) {};

Ellipse() [2/4]

lsst::gauss2d::Ellipse::Ellipse ( double sigma_x = 0, double sigma_y = 0, double rho = 0 )

explicit

Construct a new Ellipse object with default float values.

Parameters

sigma_x	The initial sigma_x value (default 0)
sigma_y	The initial sigma_y value (default 0)
rho	The intial rho value (default 0)

Definition at line 235 of file ellipse.cc.

                                                           : _data(std::make_shared<EllipseValues>()) {
    _data->set(sigma_x, sigma_y, rho);
}

Ellipse() [3/4]

lsst::gauss2d::Ellipse::Ellipse ( const Covariance & covar )

explicit

Definition at line 239 of file ellipse.cc.

: _data(std::make_shared<EllipseValues>()) { this->set(covar); }

Ellipse() [4/4]

lsst::gauss2d::Ellipse::Ellipse ( const EllipseMajor & ellipse )

explicit

Definition at line 241 of file ellipse.cc.

                                            : _data(std::make_shared<EllipseValues>()) {
    this->set(ellipse);
}

Member Function Documentation

check()

static void lsst::gauss2d::EllipseData::check ( double size_x, double size_y, double rho, std::string_view error_suffix = "" )

inlinestaticinherited

Check whether Ellipse parameter values are valid, throwing if not.

Definition at line 137 of file ellipse.h.

                                                                                                  {
        if (!(size_x >= 0) || !(size_y >= 0) || !(rho >= -1 && rho <= 1)) {
            throw std::invalid_argument("Invalid size_x, size_y, rho=" + to_string_float(size_x) + ","
                                        + to_string_float(size_y) + "," + to_string_float(rho)
                                        + "; sigma_x,y >= 0 and 1 >= rho >= -1 required."
                                        + std::string(error_suffix));
        }
    }

check_rho()

static void lsst::gauss2d::EllipseData::check_rho ( double rho, std::string_view error_suffix = "" )

inlinestaticinherited

Check whether a rho value is valid.

Definition at line 153 of file ellipse.h.

                                                                        {
        if (!(rho >= -1 && rho <= 1)) {
            throw std::invalid_argument("Invalid rho=" + to_string_float(rho) + "; 1 >= rho >= -1 required."
                                        + std::string(error_suffix));
        }
    }

check_size()

static void lsst::gauss2d::EllipseData::check_size ( double size, std::string_view error_suffix = "" )

inlinestaticinherited

Check whether an x- or x-yaxis size value is valid.

Definition at line 146 of file ellipse.h.

                                                                          {
        if (!(size >= 0)) {
            throw std::invalid_argument("Invalid size=" + to_string_float(size) + "; size >= 0 required."
                                        + std::string(error_suffix));
        }
    }

convolve()

void lsst::gauss2d::EllipseData::convolve ( const Ellipse & ell )

virtualinherited

Convolve this ellipse with another.

Definition at line 149 of file ellipse.cc.

                                             {
    double sigma_x_ell = ell.get_sigma_x();
    double sigma_y_ell = ell.get_sigma_y();
    double sigma_x = this->get_sigma_x();
    sigma_x = sqrt(sigma_x * sigma_x + sigma_x_ell * sigma_x_ell);
    double sigma_y = this->get_sigma_y();
    sigma_y = sqrt(sigma_y * sigma_y + sigma_y_ell * sigma_y_ell);
    double rho = (this->get_cov_xy() + ell.get_cov_xy()) / (sigma_x * sigma_y);
    this->set(sigma_x, sigma_y, rho);
}

get_area()

double lsst::gauss2d::EllipseData::get_area ( ) const

virtualinherited

Return the area of this ellipse, equal to pi*sigma_major*sigma_minor.

Definition at line 142 of file ellipse.cc.

                                   {
    double rho = this->get_rho();
    return M_PI * this->get_sigma_xy() * sqrt(1 - rho * rho);
}

get_cov_xy()

double lsst::gauss2d::EllipseData::get_cov_xy ( ) const

virtualinherited

Return the covariance, equal to sigma_x*sigma_y*rho.

Definition at line 160 of file ellipse.cc.

{ return this->get_sigma_x() * this->get_sigma_y() * this->get_rho(); }

get_data()

const EllipseData & lsst::gauss2d::Ellipse::get_data

(

)

const

Return a const ref to this ellipse's data.

Definition at line 318 of file ellipse.cc.

{ return *this->_data; }

get_hwhm_x()

double lsst::gauss2d::EllipseData::get_hwhm_x ( ) const

virtualinherited

Get the x-axis half-width at half-maximum.

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse.

Definition at line 162 of file ellipse.cc.

{ return M_SIGMA_HWHM * this->get_sigma_x(); };

get_hwhm_y()

double lsst::gauss2d::EllipseData::get_hwhm_y ( ) const

virtualinherited

Get the y-axis half-width at half-maximum.

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse.

Definition at line 164 of file ellipse.cc.

{ return M_SIGMA_HWHM * this->get_sigma_y(); };

get_hxyr()

std::array< double, 3 > lsst::gauss2d::EllipseData::get_hxyr ( ) const

virtualinherited

Get hwhm_x, hwhm_y, rho.

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse.

Definition at line 166 of file ellipse.cc.

                                                {
    return {this->get_hwhm_x(), this->get_hwhm_y(), this->get_rho()};
}

get_radius_trace()

double lsst::gauss2d::EllipseData::get_radius_trace ( ) const

virtualinherited

Return the trace radius, equal to sqrt(sigma_x^2 + sigma_y^2)

Definition at line 173 of file ellipse.cc.

{ return sqrt(this->get_sigma_x_sq() + this->get_sigma_y_sq()); }

get_rho()

double lsst::gauss2d::Ellipse::get_rho ( ) const

overridevirtual

Get rho.

Implements lsst::gauss2d::EllipseData.

Definition at line 319 of file ellipse.cc.

{ return this->_data->get_rho(); }

get_sigma_x()

double lsst::gauss2d::Ellipse::get_sigma_x ( ) const

overridevirtual

Get sigma_x.

Implements lsst::gauss2d::EllipseData.

Definition at line 320 of file ellipse.cc.

{ return this->_data->get_sigma_x(); }

get_sigma_x_sq()

double lsst::gauss2d::EllipseData::get_sigma_x_sq ( ) const

virtualinherited

Get the square of sigma_x.

Definition at line 175 of file ellipse.cc.

                                         {
    double sigma = this->get_sigma_x();
    return sigma * sigma;
}

get_sigma_xy()

double lsst::gauss2d::EllipseData::get_sigma_xy ( ) const

virtualinherited

Return sigma_x*sigma_y.

Definition at line 147 of file ellipse.cc.

{ return this->get_sigma_x() * this->get_sigma_y(); }

get_sigma_y()

double lsst::gauss2d::Ellipse::get_sigma_y ( ) const

overridevirtual

Get sigma_y.

Implements lsst::gauss2d::EllipseData.

Definition at line 321 of file ellipse.cc.

{ return this->_data->get_sigma_y(); }

get_sigma_y_sq()

double lsst::gauss2d::EllipseData::get_sigma_y_sq ( ) const

virtualinherited

Get the square of sigma_y.

Definition at line 180 of file ellipse.cc.

                                         {
    double sigma = this->get_sigma_y();
    return sigma * sigma;
}

get_xyr()

std::array< double, 3 > lsst::gauss2d::EllipseData::get_xyr ( ) const

virtualinherited

Get sigma_x, sigma_y, rho.

Reimplemented in lsst::gauss2d::EllipseValues, lsst::gauss2d::fit::GaussianParametricEllipse, and lsst::gauss2d::fit::SersicEllipseData.

Definition at line 169 of file ellipse.cc.

                                               {
    return {this->get_sigma_x(), this->get_sigma_y(), this->get_rho()};
}

make_convolution()

std::shared_ptr< Ellipse > lsst::gauss2d::Ellipse::make_convolution

(

const Ellipse &

ell

)

const

Return the convolution of this with another ellipse.

Convolution simply sums the values of the covariance matrix terms.

Parameters

ell	The ellipse to convolve with.

Returns

A new ellipse with values set to the convolution.

Definition at line 245 of file ellipse.cc.

                                                                         {
    return this->make_convolution_uniq(ell);
}

make_convolution_uniq()

std::unique_ptr< Ellipse > lsst::gauss2d::Ellipse::make_convolution_uniq

(

const Ellipse &

ell

)

const

Same as make_convolution(), but returning a unique_ptr.

Definition at line 248 of file ellipse.cc.

                                                                              {
    // TODO: Replace with cloning derived data
    std::unique_ptr<Ellipse> ell_ret
            = std::make_unique<Ellipse>(this->get_sigma_x(), this->get_sigma_y(), this->get_rho());
    ell_ret->convolve(ell);
    return ell_ret;
}

null_str()

static std::string_view lsst::gauss2d::Object::null_str ( const std::string_view & namespace_separator )

inlinestaticinherited

Definition at line 49 of file object.h.

                                                                              {
        return namespace_separator == CC_NAMESPACE_SEPARATOR ? "nullptr" : NULL_STR_GENERAL;
    }

operator!=() [1/2]

bool lsst::gauss2d::Ellipse::operator!=

(

const Ellipse &

other

)

const

Definition at line 316 of file ellipse.cc.

{ return !(*this == other); }

operator!=() [2/2]

bool lsst::gauss2d::EllipseData::operator!= ( const EllipseData & other ) const

inlineinherited

Definition at line 217 of file ellipse.h.

{ return !(*this == other); };

operator==() [1/2]

bool lsst::gauss2d::Ellipse::operator==

(

const Ellipse &

other

)

const

Definition at line 315 of file ellipse.cc.

{ return get_data() == other.get_data(); };

operator==() [2/2]

bool lsst::gauss2d::EllipseData::operator== ( const EllipseData & other ) const

inlineinherited

Definition at line 216 of file ellipse.h.

{ return get_xyr() == other.get_xyr(); };

repr()

std::string lsst::gauss2d::Ellipse::repr ( bool name_keywords = false, std::string_view namespace_separator = Object::CC_NAMESPACE_SEPARATOR ) const

overridevirtual

Return a full, callable string representation of this.

Parameters

name_keywords	Whether to prefix arguments with "{name}=", where name is the arg name in the header (as with keyword arguments in Python).
namespace_separator	The string to use to delimit namespaces, i.e. :: in C++ and . in Python.

Returns

A callable string representation of this, which should return an an identical object to this.

Note

The representation with name_keywords=false must be callable in C++. The representation with name_keywords=true should be callable in Python, if there are any bindings.

Implements lsst::gauss2d::EllipseData.

Definition at line 308 of file ellipse.cc.

                                                                                    {
    return type_name_str<Ellipse>(false, namespace_separator) + "(" + (name_keywords ? "data=" : "")
           + _data->repr(name_keywords, namespace_separator) + ")";
}

set() [1/3]

void lsst::gauss2d::EllipseData::set ( const Covariance & covar )

virtualinherited

Set values from a Covariance object.

Definition at line 263 of file ellipse.cc.

                                             {
    double sigma_x = covar.get_sigma_x_sq();
    double sigma_y = covar.get_sigma_y_sq();
    sigma_x = sqrt(sigma_x);
    sigma_y = sqrt(sigma_y);
    double rho = (sigma_x == 0 || sigma_y == 0) ? 0 : covar.get_cov_xy() / (sigma_x * sigma_y);
    this->set(sigma_x, sigma_y, rho);
}

set() [2/3]

void lsst::gauss2d::EllipseData::set ( const EllipseMajor & ellipse )

virtualinherited

Set values from an EllipseMajor object.

Definition at line 272 of file ellipse.cc.

                                                 {
    const double r_major = ellipse.get_r_major();
    if (r_major == 0) {
        this->set(0, 0, 0);
        return;
    }
    const double axrat = ellipse.get_axrat();
    if (axrat == 1) {
        this->set(r_major, r_major, 0);
        return;
    }
    const auto [sin_th, cos_th] = sincos(ellipse.get_angle_radians());
    const double sin_th_sq = sin_th * sin_th;
    const double cos_th_sq = cos_th * cos_th;
 
    const double r_major_sq = r_major * r_major;
    const double r_minor_sq = r_major_sq * axrat * axrat;
    const double sigma_x = sqrt(cos_th_sq * r_major_sq + sin_th_sq * r_minor_sq);
    const double sigma_y = sqrt(sin_th_sq * r_major_sq + cos_th_sq * r_minor_sq);
    double rho = (sigma_x == 0 || sigma_y == 0)
                         ? 0
                         : sin_th * cos_th * (r_major_sq - r_minor_sq) / (sigma_x * sigma_y);
    this->set(sigma_x, sigma_y, rho);
}

set() [3/3]

void lsst::gauss2d::EllipseData::set ( double sigma_x, double sigma_y, double rho )

virtualinherited

Set sigma_x, sigma_y, rho.

Reimplemented in lsst::gauss2d::EllipseValues, lsst::gauss2d::fit::GaussianParametricEllipse, and lsst::gauss2d::fit::SersicEllipseData.

Definition at line 256 of file ellipse.cc.

                                                                {
    this->check(sigma_x, sigma_y, rho);
    this->set_sigma_x(sigma_x);
    this->set_sigma_y(sigma_y);
    this->set_rho(rho);
}

set_h()

void lsst::gauss2d::EllipseData::set_h ( double hwhm_x, double hwhm_y, double rho )

virtualinherited

Set hwhm_x, hwhm_y, rho (half-width at half-max)

Reimplemented in lsst::gauss2d::EllipseValues, lsst::gauss2d::fit::GaussianParametricEllipse, and lsst::gauss2d::fit::SersicEllipseData.

Definition at line 297 of file ellipse.cc.

                                                                {
    EllipseData::check(hwhm_x, hwhm_y, rho);
    this->set_hwhm_x(hwhm_x);
    this->set_hwhm_y(hwhm_y);
    this->set_rho(rho);
}

set_hwhm_x()

void lsst::gauss2d::EllipseData::set_hwhm_x ( double hwhm_x )

virtualinherited

Set the x-axis half-width at half-max (FWHM/2)

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse.

Definition at line 303 of file ellipse.cc.

{ this->set_sigma_x(M_HWHM_SIGMA * hwhm_x); }

set_hwhm_y()

void lsst::gauss2d::EllipseData::set_hwhm_y ( double hwhm_y )

virtualinherited

Set the y-axis half-width at half-max (FWHM/2)

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse.

Definition at line 304 of file ellipse.cc.

{ this->set_sigma_y(M_HWHM_SIGMA * hwhm_y); }

set_hxyr()

void lsst::gauss2d::EllipseData::set_hxyr ( const std::array< double, 3 > & hxyr )

virtualinherited

Set hwhm_x, hwhm_y, rho from an array.

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse, and lsst::gauss2d::fit::SersicEllipseData.

Definition at line 305 of file ellipse.cc.

{ this->set_h(hxyr[0], hxyr[1], hxyr[2]); }

set_rho()

void lsst::gauss2d::Ellipse::set_rho ( double rho )

overridevirtual

Set the correlation parameter (rho)

Implements lsst::gauss2d::EllipseData.

Definition at line 323 of file ellipse.cc.

{ this->_data->set_rho(rho); }

set_sigma_x()

void lsst::gauss2d::Ellipse::set_sigma_x ( double sigma_x )

overridevirtual

Set the x-axis dispersion (sigma)

Implements lsst::gauss2d::EllipseData.

Definition at line 324 of file ellipse.cc.

{ this->_data->set_sigma_x(sigma_x); }

set_sigma_y()

void lsst::gauss2d::Ellipse::set_sigma_y ( double sigma_y )

overridevirtual

Set the y-axis dispersion (sigma)

Implements lsst::gauss2d::EllipseData.

Definition at line 325 of file ellipse.cc.

{ this->_data->set_sigma_y(sigma_y); }

set_xyr()

void lsst::gauss2d::EllipseData::set_xyr ( const std::array< double, 3 > & xyr )

virtualinherited

Set sigma_x, sigma_y, rho from an array.

Reimplemented in lsst::gauss2d::fit::GaussianParametricEllipse, and lsst::gauss2d::fit::SersicEllipseData.

Definition at line 306 of file ellipse.cc.

{ this->set(xyr[0], xyr[1], xyr[2]); }

str()

std::string lsst::gauss2d::Ellipse::str ( ) const

overridevirtual

Return a brief, human-readable string representation of this.

Implements lsst::gauss2d::EllipseData.

Definition at line 313 of file ellipse.cc.

{ return type_name_str<Ellipse>(true) + "(data=" + _data->str() + ")"; }

Member Data Documentation

CC_NAMESPACE_SEPARATOR

constexpr std::string_view lsst::gauss2d::Object::CC_NAMESPACE_SEPARATOR = "::"

staticconstexprinherited

The C++ namespace separator.

Definition at line 45 of file object.h.

NULL_STR_GENERAL

constexpr std::string_view lsst::gauss2d::Object::NULL_STR_GENERAL = "None"

staticconstexprinherited

Definition at line 46 of file object.h.

PY_NAMESPACE_SEPARATOR

constexpr std::string_view lsst::gauss2d::Object::PY_NAMESPACE_SEPARATOR = "."

staticconstexprinherited

Definition at line 47 of file object.h.

---

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/gauss2d/g9125e01d80+a8ce1bb630/include/lsst/gauss2d/ellipse.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/gauss2d/g9125e01d80+a8ce1bb630/src/ellipse.cc