lsst::afw::geom::ellipses::Distortion Class Reference

A complex ellipticity with magnitude \(|e| = \frac{a^2 - b^2}{a^2 + b^2}\). More...

#include <Distortion.h>

Inheritance diagram for lsst::afw::geom::ellipses::Distortion:

Public Types
enum	ParameterEnum { E1 = 0 , E2 = 1 }
using	Jacobian = Eigen::Matrix2d

Public Member Functions
	Distortion (std::complex< double > const &complex)
	Distortion (double e1=0.0, double e2=0.0)
	Distortion (Distortion const &other)
	Distortion (Distortion &&other)
	~Distortion ()=default
	Distortion (ConformalShear const &other)
	Distortion (ReducedShear const &other)
Distortion &	operator= (Distortion const &other)
Distortion &	operator= (Distortion &&other)
Distortion &	operator= (ConformalShear const &other)
Distortion &	operator= (ReducedShear const &other)
Jacobian	dAssign (Distortion const &other)
Jacobian	dAssign (ConformalShear const &other)
Jacobian	dAssign (ReducedShear const &other)
double	getAxisRatio () const
void	normalize ()
std::complex< double > &	getComplex ()
std::complex< double > const &	getComplex () const
void	setComplex (std::complex< double > const &v)
double	getE1 () const
void	setE1 (double e1)
double	getE2 () const
void	setE2 (double e2)
double	getE () const
void	setE (double e)
double	getTheta () const

Static Public Member Functions
static std::string	getName ()

Protected Attributes
std::complex< double >	_complex

Detailed Description

A complex ellipticity with magnitude \(|e| = \frac{a^2 - b^2}{a^2 + b^2}\).

For a more complete definition, see Bernstein and Jarvis (2002); this the same as their distortion \(\delta\) (eq. 2.7).

Definition at line 44 of file Distortion.h.

Member Typedef Documentation

Jacobian

using lsst::afw::geom::ellipses::detail::EllipticityBase::Jacobian = Eigen::Matrix2d

inherited

Definition at line 47 of file EllipticityBase.h.

Member Enumeration Documentation

ParameterEnum

enum lsst::afw::geom::ellipses::detail::EllipticityBase::ParameterEnum

inherited

Enumerator
E1
E2

Definition at line 49 of file EllipticityBase.h.

{ E1 = 0, E2 = 1 };

Constructor & Destructor Documentation

Distortion() [1/6]

lsst::afw::geom::ellipses::Distortion::Distortion ( std::complex< double > const & complex )

inlineexplicit

Definition at line 46 of file Distortion.h.

: detail::EllipticityBase(complex) {}

Distortion() [2/6]

lsst::afw::geom::ellipses::Distortion::Distortion ( double e1 = 0.0, double e2 = 0.0 )

inlineexplicit

Definition at line 48 of file Distortion.h.

: detail::EllipticityBase(e1, e2) {}

Distortion() [3/6]

lsst::afw::geom::ellipses::Distortion::Distortion ( Distortion const & other )

inline

Definition at line 50 of file Distortion.h.

: detail::EllipticityBase(other.getComplex()) {}

Distortion() [4/6]

lsst::afw::geom::ellipses::Distortion::Distortion ( Distortion && other )

inline

Definition at line 52 of file Distortion.h.

: Distortion(other) {}

~Distortion()

lsst::afw::geom::ellipses::Distortion::~Distortion ( )

default

Distortion() [5/6]

lsst::afw::geom::ellipses::Distortion::Distortion ( ConformalShear const & other )

inlineexplicit

Definition at line 55 of file Distortion.h.

{ this->operator=(other); }

Distortion() [6/6]

lsst::afw::geom::ellipses::Distortion::Distortion ( ReducedShear const & other )

inlineexplicit

Definition at line 57 of file Distortion.h.

{ this->operator=(other); }

Member Function Documentation

dAssign() [1/3]

detail::EllipticityBase::Jacobian lsst::afw::geom::ellipses::Distortion::dAssign

(

ConformalShear const &

other

)

Definition at line 56 of file Distortion.cc.

                                                                             {
    Jacobian result = Jacobian::Zero();
    double eta = other.getE();
    double alpha, beta;
    if (eta < 1E-8) {
        alpha = (1.0 - eta * eta / 3.0);
        beta = -2.0 / 3.0;
    } else {
        double delta = std::tanh(eta);
        alpha = delta / eta;
        beta = (1.0 - delta * delta - alpha) / (eta * eta);
    }
    _complex = other.getComplex() * alpha;
    result(0, 0) = alpha + other.getE1() * other.getE1() * beta;
    result(1, 1) = alpha + other.getE2() * other.getE2() * beta;
    result(1, 0) = result(0, 1) = other.getE1() * other.getE2() * beta;
    return result;
}

dAssign() [2/3]

Jacobian lsst::afw::geom::ellipses::Distortion::dAssign ( Distortion const & other )

inline

Definition at line 70 of file Distortion.h.

                                              {
        _complex = other._complex;
        return Jacobian::Identity();
    }

dAssign() [3/3]

detail::EllipticityBase::Jacobian lsst::afw::geom::ellipses::Distortion::dAssign

(

ReducedShear const &

other

)

Definition at line 75 of file Distortion.cc.

                                                                           {
    Jacobian result = Jacobian::Zero();
    double g = other.getE();
    double alpha = 2.0 / (1 + g * g);
    double beta = -alpha * alpha;
    _complex = other.getComplex() * alpha;
    result(0, 0) = alpha + other.getE1() * other.getE1() * beta;
    result(1, 1) = alpha + other.getE2() * other.getE2() * beta;
    result(1, 0) = result(0, 1) = other.getE1() * other.getE2() * beta;
    return result;
}

getAxisRatio()

double lsst::afw::geom::ellipses::Distortion::getAxisRatio

(

)

const

Definition at line 34 of file Distortion.cc.

                                      {
    double e = getE();
    return std::sqrt((1.0 - e) / (1.0 + e));
}

getComplex() [1/2]

std::complex< double > & lsst::afw::geom::ellipses::detail::EllipticityBase::getComplex ( )

inlineinherited

Definition at line 51 of file EllipticityBase.h.

{ return _complex; }

getComplex() [2/2]

std::complex< double > const & lsst::afw::geom::ellipses::detail::EllipticityBase::getComplex ( ) const

inlineinherited

Definition at line 53 of file EllipticityBase.h.

{ return _complex; }

getE()

double lsst::afw::geom::ellipses::detail::EllipticityBase::getE ( ) const

inlineinherited

Definition at line 75 of file EllipticityBase.h.

{ return std::sqrt(std::norm(_complex)); }

getE1()

double lsst::afw::geom::ellipses::detail::EllipticityBase::getE1 ( ) const

inlineinherited

Definition at line 57 of file EllipticityBase.h.

{ return _complex.real(); }

getE2()

double lsst::afw::geom::ellipses::detail::EllipticityBase::getE2 ( ) const

inlineinherited

Definition at line 66 of file EllipticityBase.h.

{ return _complex.imag(); }

getName()

static std::string lsst::afw::geom::ellipses::Distortion::getName ( )

inlinestatic

Definition at line 83 of file Distortion.h.

{ return "Distortion"; }

getTheta()

double lsst::afw::geom::ellipses::detail::EllipticityBase::getTheta ( ) const

inlineinherited

Definition at line 78 of file EllipticityBase.h.

{ return 0.5 * std::arg(_complex); }

normalize()

void lsst::afw::geom::ellipses::Distortion::normalize

(

)

Definition at line 87 of file Distortion.cc.

                           {
    if (getE() > 1.0) {
        throw LSST_EXCEPT(lsst::pex::exceptions::InvalidParameterError,
                          "Distortion magnitude cannot be greater than one.");
    }
}

operator=() [1/4]

Distortion & lsst::afw::geom::ellipses::Distortion::operator=

(

ConformalShear const &

other

)

Definition at line 39 of file Distortion.cc.

                                                             {
    double eta = other.getE();
    if (eta < 1E-8) {
        _complex = other.getComplex() * (1.0 - eta * eta / 3.0);
    } else {
        double delta = std::tanh(eta);
        _complex = other.getComplex() * delta / eta;
    }
    return *this;
}

operator=() [2/4]

Distortion & lsst::afw::geom::ellipses::Distortion::operator= ( Distortion && other )

inline

Definition at line 64 of file Distortion.h.

{ return *this = other; }

operator=() [3/4]

Distortion & lsst::afw::geom::ellipses::Distortion::operator= ( Distortion const & other )

inline

Definition at line 59 of file Distortion.h.

                                                   {
        _complex = other._complex;
        return *this;
    }

operator=() [4/4]

Distortion & lsst::afw::geom::ellipses::Distortion::operator=

(

ReducedShear const &

other

)

Definition at line 50 of file Distortion.cc.

                                                           {
    double g = other.getE();
    _complex = other.getComplex() * 2.0 / (1 + g * g);
    return *this;
}

setComplex()

void lsst::afw::geom::ellipses::detail::EllipticityBase::setComplex ( std::complex< double > const & v )

inlineinherited

Definition at line 55 of file EllipticityBase.h.

{ _complex = v; }

setE()

void lsst::afw::geom::ellipses::detail::EllipticityBase::setE ( double e )

inlineinherited

Definition at line 76 of file EllipticityBase.h.

{ _complex *= e / getE(); }

setE1()

void lsst::afw::geom::ellipses::detail::EllipticityBase::setE1 ( double e1 )

inlineinherited

Definition at line 58 of file EllipticityBase.h.

                          {
#if __cplusplus < 201103L
        _complex = std::complex<double>(e1, _complex.imag());
#else
        _complex.real(e1);
#endif
    }

setE2()

void lsst::afw::geom::ellipses::detail::EllipticityBase::setE2 ( double e2 )

inlineinherited

Definition at line 67 of file EllipticityBase.h.

                          {
#if __cplusplus < 201103L
        _complex = std::complex<double>(_complex.real(), e2);
#else
        _complex.imag(e2);
#endif
    }

Member Data Documentation

_complex

std::complex<double> lsst::afw::geom::ellipses::detail::EllipticityBase::_complex

protectedinherited

Definition at line 91 of file EllipticityBase.h.

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

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/afw/g5a732f18d5+53520f316c/include/lsst/afw/geom/ellipses/Distortion.h
• /j/snowflake/release/lsstsw/stack/lsst-scipipe-8.0.0/Linux64/afw/g5a732f18d5+53520f316c/src/geom/ellipses/Distortion.cc