CTA 2D point spread function class. More...

#include <GCTAPsf2D.hpp>

Inheritance diagram for GCTAPsf2D:

Public Member Functions
	GCTAPsf2D (void)
	Void constructor. More...

	GCTAPsf2D (const GFilename &filename)
	File constructor. More...

	GCTAPsf2D (const GCTAPsf2D &psf)
	Copy constructor. More...

virtual	~GCTAPsf2D (void)
	Destructor. More...

GCTAPsf2D &	operator= (const GCTAPsf2D &psf)
	Assignment operator. More...

double	operator() (const double &delta, const double &logE, const double &theta=0.0, const double &phi=0.0, const double &zenith=0.0, const double &azimuth=0.0, const bool &etrue=true) const
	Return point spread function (in units of sr^-1) More...

void	clear (void)
	Clear point spread function. More...

GCTAPsf2D *	clone (void) const
	Clone point spread functions. More...

std::string	classname (void) const
	Return class name. More...

void	load (const GFilename &filename)
	Load point spread function from FITS file. More...

GFilename	filename (void) const
	Return filename. More...

double	mc (GRan &ran, const double &logE, const double &theta=0.0, const double &phi=0.0, const double &zenith=0.0, const double &azimuth=0.0, const bool &etrue=true) const
	Simulate PSF offset (radians) More...

double	delta_max (const double &logE, const double &theta=0.0, const double &phi=0.0, const double &zenith=0.0, const double &azimuth=0.0, const bool &etrue=true) const
	Return maximum size of PSF (radians) More...

double	containment_radius (const double &fraction, const double &logE, const double &theta=0.0, const double &phi=0.0, const double &zenith=0.0, const double &azimuth=0.0, const bool &etrue=true) const
	Return the radius that contains a fraction of the events (radians) More...

std::string	print (const GChatter &chatter=NORMAL) const
	Print point spread function information. More...

const GCTAResponseTable &	table (void) const
	Return response table. More...

void	table (const GCTAResponseTable &table)
	Assign response table. More...

void	read (const GFitsTable &table)
	Read point spread function from FITS table. More...

void	write (GFitsBinTable &table) const
	Write point spread function into FITS binary table. More...

void	save (const GFilename &filename, const bool &clobber=false) const
	Save point spread function table into FITS file. More...

Public Member Functions inherited from GCTAPsf
	GCTAPsf (void)
	Void constructor. More...

	GCTAPsf (const GCTAPsf &psf)
	Copy constructor. More...

virtual	~GCTAPsf (void)
	Destructor. More...

GCTAPsf &	operator= (const GCTAPsf &psf)
	Assignment operator. More...

Public Member Functions inherited from GBase
virtual	~GBase (void)
	Destructor. More...

Private Member Functions
void	init_members (void)
	Initialise class members. More...

void	copy_members (const GCTAPsf2D &psf)
	Copy class members. More...

void	free_members (void)
	Delete class members. More...

void	update (const double &logE, const double &theta) const
	Update PSF parameter cache. More...

Private Attributes
GFilename	m_filename
	Name of Aeff response file. More...

GCTAResponseTable	m_psf
	PSF response table. More...

int	m_inx_energy
	Energy index. More...

int	m_inx_theta
	Theta index. More...

int	m_inx_sigma1
	1st Gaussian sigma More...

int	m_inx_ampl2
	2nd Gaussian relative amplitude More...

int	m_inx_sigma2
	2nd Gaussian sigma More...

int	m_inx_ampl3
	3nd Gaussian relative amplitude More...

int	m_inx_sigma3
	3nd Gaussian sigma More...

double	m_par_logE
	Cache energy. More...

double	m_par_theta
	Cache offset angle. More...

double	m_norm
	Global normalization. More...

double	m_norm2
	Gaussian 2 normalization. More...

double	m_norm3
	Gaussian 3 normalization. More...

double	m_sigma1
	Gaussian 1 sigma. More...

double	m_sigma2
	Gaussian 2 sigma. More...

double	m_sigma3
	Gaussian 3 sigma. More...

double	m_width1
	Gaussian 1 width. More...

double	m_width2
	Gaussian 2 width. More...

double	m_width3
	Gaussian 3 width. More...

Additional Inherited Members
Protected Member Functions inherited from GCTAPsf
void	init_members (void)
	Initialise class members. More...

void	copy_members (const GCTAPsf &psf)
	Copy class members. More...

void	free_members (void)
	Delete class members. More...

Detailed Description

CTA 2D point spread function class.

This class implements the CTA point spread function response as function of energy and offset angle.

Definition at line 54 of file GCTAPsf2D.hpp.

Constructor & Destructor Documentation

GCTAPsf2D::GCTAPsf2D ( void )

Void constructor.

Constructs empty point spread function.

Definition at line 68 of file GCTAPsf2D.cpp.

References init_members().

Referenced by clone().

GCTAPsf2D::GCTAPsf2D ( const GFilename & filename )

explicit

File constructor.

Parameters

[in] filename FITS file name.

Constructs point spread function from a FITS file.

Definition at line 85 of file GCTAPsf2D.cpp.

References init_members(), and load().

GCTAPsf2D::GCTAPsf2D ( const GCTAPsf2D & psf )

Copy constructor.

Parameters

[in] psf Point spread function.

Constructs point spread function by copying from another point spread function.

Definition at line 106 of file GCTAPsf2D.cpp.

References copy_members(), and init_members().

GCTAPsf2D::~GCTAPsf2D ( void )

virtual

Destructor.

Destructs point spread function.

Definition at line 124 of file GCTAPsf2D.cpp.

References free_members().

Member Function Documentation

std::string GCTAPsf2D::classname ( void ) const

inlinevirtual

Return class name.

Returns: String containing the class name ("GCTAPsf2D").

Implements GCTAPsf.

Definition at line 149 of file GCTAPsf2D.hpp.

void GCTAPsf2D::clear ( void )

virtual

Clear point spread function.

Clears point spread function.

Implements GCTAPsf.

Definition at line 259 of file GCTAPsf2D.cpp.

References GCTAPsf::free_members(), free_members(), GCTAPsf::init_members(), and init_members().

GCTAPsf2D * GCTAPsf2D::clone ( void ) const

virtual

Clone point spread functions.

Returns: Deep copy of point spread function.

Returns a pointer to a deep copy of the point spread function.

Implements GCTAPsf.

Definition at line 281 of file GCTAPsf2D.cpp.

References GCTAPsf2D().

double GCTAPsf2D::containment_radius	(	const double &	fraction,
		const double &	logE,
		const double &	theta = `0.0`,
		const double &	phi = `0.0`,
		const double &	zenith = `0.0`,
		const double &	azimuth = `0.0`,
		const bool &	etrue = `true`
	)		const

virtual

Return the radius that contains a fraction of the events (radians)

Parameters

[in]	fraction	of events (0.0 < fraction < 1.0)
[in]	logE	Log10 of the true photon energy (TeV).
[in]	theta	Offset angle in camera system (rad).
[in]	phi	Azimuth angle in camera system (rad). Not used.
[in]	zenith	Zenith angle in Earth system (rad). Not used.
[in]	azimuth	Azimuth angle in Earth system (rad). Not used.
[in]	etrue	Use true energy (true/false). Not used.

Returns: Containment radius (radians).

Exceptions

GException::invalid_argument Invalid fraction specified.

Uses the Newton-Raphson method to find which 'a' solves the equation:

\[ fraction = m\_norm * \left( e^{m\_width1 * a^2} + m\_norm2 * e^{m\_width2 * a^2} + m\_norm3 * e^{m\_width3 * a^2} \right) \]

Calculate the radius from the center that contains fraction of the events (fraction * 100. = Containment % ). Fraction must be

\[ 0.0 < fraction < 1.0 \]

Implements GCTAPsf.

Definition at line 586 of file GCTAPsf2D.cpp.

References abs(), delta_max(), exp(), G_CONTAINMENT_RADIUS, m_norm, m_norm2, m_norm3, m_width1, m_width2, m_width3, gammalib::pi, gammalib::str(), update(), and gammalib::warning().

void GCTAPsf2D::copy_members ( const GCTAPsf2D & psf )

private

Copy class members.

Parameters

[in] psf Point spread function.

Definition at line 779 of file GCTAPsf2D.cpp.

References m_filename, m_inx_ampl2, m_inx_ampl3, m_inx_energy, m_inx_sigma1, m_inx_sigma2, m_inx_sigma3, m_inx_theta, m_norm, m_norm2, m_norm3, m_par_logE, m_par_theta, m_psf, m_sigma1, m_sigma2, m_sigma3, m_width1, m_width2, and m_width3.

Referenced by GCTAPsf2D(), and operator=().

double GCTAPsf2D::delta_max	(	const double &	logE,
		const double &	theta = `0.0`,
		const double &	phi = `0.0`,
		const double &	zenith = `0.0`,
		const double &	azimuth = `0.0`,
		const bool &	etrue = `true`
	)		const

virtual

Return maximum size of PSF (radians)

Parameters

[in]	logE	Log10 of the true photon energy (TeV).
[in]	theta	Offset angle in camera system (rad). Not used.
[in]	phi	Azimuth angle in camera system (rad). Not used.
[in]	zenith	Zenith angle in Earth system (rad). Not used.
[in]	azimuth	Azimuth angle in Earth system (rad). Not used.
[in]	etrue	Use true energy (true/false). Not used.

Determine the radius beyond which the PSF becomes negligible. This radius is set by this method to \(5 \times \sigma\), where \(\sigma\) is the Gaussian width of the largest PSF component.

Implements GCTAPsf.

Definition at line 531 of file GCTAPsf2D.cpp.

References m_sigma1, m_sigma2, m_sigma3, and update().

Referenced by containment_radius().

GFilename GCTAPsf2D::filename ( void ) const

inlinevirtual

Return filename.

Returns: Returns filename from which point spread function was loaded

Implements GCTAPsf.

Definition at line 161 of file GCTAPsf2D.hpp.

References m_filename.

Referenced by load().

void GCTAPsf2D::free_members ( void )

private

Delete class members.

Definition at line 811 of file GCTAPsf2D.cpp.

Referenced by clear(), operator=(), and ~GCTAPsf2D().

void GCTAPsf2D::init_members ( void )

private

Initialise class members.

Definition at line 745 of file GCTAPsf2D.cpp.

References GCTAResponseTable::clear(), GFilename::clear(), m_filename, m_inx_ampl2, m_inx_ampl3, m_inx_energy, m_inx_sigma1, m_inx_sigma2, m_inx_sigma3, m_inx_theta, m_norm, m_norm2, m_norm3, m_par_logE, m_par_theta, m_psf, m_sigma1, m_sigma2, m_sigma3, m_width1, m_width2, and m_width3.

Referenced by clear(), GCTAPsf2D(), and operator=().

void GCTAPsf2D::load ( const GFilename & filename )

virtual

Load point spread function from FITS file.

Parameters

[in] filename FITS file name.

Loads the point spread function from a FITS file.

If no extension name is given the method scans the HDUCLASS keywords of all extensions and loads the background from the first extension for which HDUCLAS4=PSF_3GAUSS.

Otherwise, the background will be loaded from the POINT SPREAD FUNCTION extension.

Implements GCTAPsf.

Definition at line 397 of file GCTAPsf2D.cpp.

References GFits::close(), GFilename::extname(), gammalib::extname_cta_psf2d, filename(), gammalib::gadf_hduclas4(), m_filename, read(), GFits::table(), and table().

Referenced by GCTAPsf2D().

double GCTAPsf2D::mc	(	GRan &	ran,
		const double &	logE,
		const double &	theta = `0.0`,
		const double &	phi = `0.0`,
		const double &	zenith = `0.0`,
		const double &	azimuth = `0.0`,
		const bool &	etrue = `true`
	)		const

virtual

Simulate PSF offset (radians)

Parameters

[in]	ran	Random number generator.
[in]	logE	Log10 of the true photon energy (TeV).
[in]	theta	Offset angle in camera system (rad).
[in]	phi	Azimuth angle in camera system (rad). Not used.
[in]	zenith	Zenith angle in Earth system (rad). Not used.
[in]	azimuth	Azimuth angle in Earth system (rad). Not used.
[in]	etrue	Use true energy (true/false). Not used.

Draws a random offset for a three component Gaussian PSF.

Implements GCTAPsf.

Definition at line 484 of file GCTAPsf2D.cpp.

References GRan::chisq2(), m_norm2, m_norm3, m_sigma1, m_sigma2, m_sigma3, sum(), GRan::uniform(), and update().

double GCTAPsf2D::operator()	(	const double &	delta,
		const double &	logE,
		const double &	theta = `0.0`,
		const double &	phi = `0.0`,
		const double &	zenith = `0.0`,
		const double &	azimuth = `0.0`,
		const bool &	etrue = `true`
	)		const

virtual

Return point spread function (in units of sr^-1)

Parameters

[in]	delta	Angular separation between true and measured photon directions (rad).
[in]	logE	Log10 of the true photon energy (TeV).
[in]	theta	Offset angle in camera system (rad). Defaults to 0.0.
[in]	phi	Azimuth angle in camera system (rad). Not used.
[in]	zenith	Zenith angle in Earth system (rad). Not used.
[in]	azimuth	Azimuth angle in Earth system (rad). Not used.
[in]	etrue	Use true energy (true/false). Not used.

Returns the point spread function for a given angular separation in units of sr^-1 for a given energy and offset angle.

Implements GCTAPsf.

Definition at line 187 of file GCTAPsf2D.cpp.

References exp(), m_norm, m_norm2, m_norm3, m_width1, m_width2, m_width3, and update().

GCTAPsf2D & GCTAPsf2D::operator= ( const GCTAPsf2D & psf )

Assignment operator.

Parameters

[in] psf Point spread function.

Returns: Point spread function.

Assigns point spread function.

Definition at line 148 of file GCTAPsf2D.cpp.

References copy_members(), free_members(), init_members(), and GCTAPsf::operator=().

std::string GCTAPsf2D::print ( const GChatter & chatter = NORMAL ) const

virtual

Print point spread function information.

Parameters

[in] chatter Chattiness.

Returns: String containing point spread function information.

Implements GCTAPsf.

Definition at line 689 of file GCTAPsf2D.cpp.

References GCTAResponseTable::axes(), GCTAResponseTable::axis_bins(), GCTAResponseTable::axis_hi(), GCTAResponseTable::axis_lo(), m_filename, m_inx_energy, m_inx_theta, m_psf, gammalib::parformat(), SILENT, and gammalib::str().

void GCTAPsf2D::read ( const GFitsTable & table )

Read point spread function from FITS table.

Parameters

[in] table FITS table.

Exceptions

GException::invalid_value Response table is not two-dimensional.

Reads the point spread function form the FITS table. The following column names are mandatory:

ENERG_LO - Energy lower bin boundaries
ENERG_HI - Energy upper bin boundaries
THETA_LO - Offset angle lower bin boundaries
THETA_HI - Offset angle upper bin boundaries
SIGMA_1  - 1st Gaussian sigma
AMPL_2   - 2nd Gaussian relative amplitude
SIGMA_2  - 2nd Gaussian sigma
AMPL_3   - 3rd Gaussian relative amplitude
SIGMA_3  - 3rd Gaussian sigma

The data are stored in the m_psf member. The energy axis will be set to log10, the offset angle axis to radians.

Definition at line 311 of file GCTAPsf2D.cpp.

References GCTAResponseTable::axes(), GCTAResponseTable::axis(), GCTAResponseTable::axis_log10(), GCTAResponseTable::axis_radians(), GCTAResponseTable::clear(), gammalib::deg2rad, G_READ, m_inx_ampl2, m_inx_ampl3, m_inx_energy, m_inx_sigma1, m_inx_sigma2, m_inx_sigma3, m_inx_theta, m_psf, GCTAResponseTable::read(), GCTAResponseTable::scale(), gammalib::str(), and GCTAResponseTable::table().