Describes a multiplet of Gaussian shaped spectral lines. More...

#include <GaussianMultipletSpectralElement.h>

Inheritance diagram for casa::GaussianMultipletSpectralElement:

Public Member Functions
	GaussianMultipletSpectralElement (const std::vector< GaussianSpectralElement > &estimates, const casacore::Matrix< casacore::Double > &fixedRelationships)
	Construct a Gaussian multiplet. More...

	GaussianMultipletSpectralElement (const GaussianMultipletSpectralElement &other)
	copy semantics More...

	~GaussianMultipletSpectralElement ()

SpectralElement *	clone () const

GaussianMultipletSpectralElement &	operator= (const GaussianMultipletSpectralElement &other)
	copy semantics More...

casacore::Bool	operator== (const GaussianMultipletSpectralElement &other) const

const std::vector < GaussianSpectralElement > &	getGaussians () const
	get the gaussians More...

const casacore::Matrix < casacore::Double > &	getConstraints () const
	get the constraints matrix More...

void	set (const casacore::Vector< casacore::Double > &param)
	These methods must be public because the architecture of the class hierarchy requires it and set() and setError() must be accessible by fitters. More...

void	setError (const casacore::Vector< casacore::Double > &err)
	Set the error fields. More...

void	fix (const casacore::Vector< casacore::Bool > &fix)
	Set fixed parameters (true) or unset them (false) More...

casacore::Bool	toRecord (casacore::RecordInterface &out) const
	Save to a record. More...

Public Member Functions inherited from casa::CompiledSpectralElement
	CompiledSpectralElement (const casacore::String &function, const casacore::Vector< casacore::Double > &param)
	Construct a compiled string. More...

	CompiledSpectralElement (const CompiledSpectralElement &other)

virtual	~CompiledSpectralElement ()

CompiledSpectralElement &	operator= (const CompiledSpectralElement &other)

virtual casacore::Double	operator() (const casacore::Double x) const
	Evaluate the value of the element at x. More...

*const casacore::String &	getFunction () const
	Get the string of a compiled functional. More...

Public Member Functions inherited from casa::SpectralElement
virtual	~SpectralElement ()

casacore::Bool	operator== (const SpectralElement &other) const

virtual casacore::Double	operator[] (const casacore::uInt n) const
	Get parameter n. More...

SpectralElement::Types	getType () const
	Get type of this element. More...

void	get (casacore::Vector< casacore::Double > &params) const
	Get all parameters. More...

casacore::Vector < casacore::Double >	get () const

void	getError (casacore::Vector< casacore::Double > &err) const
	Get error estimates of parameters. More...

casacore::Vector < casacore::Double >	getError () const

casacore::uInt	getOrder () const
	Get the order (i.e. More...

const casacore::Vector < casacore::Bool > &	fixed () const
	Get the fix state[s]. More...

Private Attributes
std::vector < GaussianSpectralElement >	_gaussians

casacore::Matrix < casacore::Double >	_constraints

casacore::Matrix< casacore::uInt >	_paramIndices

Additional Inherited Members
Public Types inherited from casa::SpectralElement
enum	Types { GAUSSIAN, POLYNOMIAL, COMPILED, GMULTIPLET, LORENTZIAN, POWERLOGPOLY, LOGTRANSPOLY, N_Types }
	Supported spectral components. More...

Static Public Member Functions inherited from casa::SpectralElement
static const casacore::String *	allTypes (casacore::Int &nall, const SpectralElement::Types *&typ)
	Get all the types available as casacore::String and codes, and number available. More...

static const casacore::String &	fromType (SpectralElement::Types tp)
	Get a string from the type. More...

static casacore::Bool	toType (SpectralElement::Types &tp, const casacore::String &typName)
	Get a type from a (non-case sensitive; minimum match) String. More...

Protected Member Functions inherited from casa::SpectralElement
	SpectralElement ()

	SpectralElement (Types type, const casacore::Vector< casacore::Double > &parms=casacore::Vector< casacore::Double >(0))

	SpectralElement (const SpectralElement &other)

SpectralElement &	operator= (const SpectralElement &other)

void	_set (const casacore::Vector< casacore::Double > &params)

void	_setType (const Types type)

void	_setFunction (const std::shared_ptr< casacore::Function< casacore::Double, casacore::Double > > &f)

virtual std::shared_ptr < casacore::Function < casacore::Double, casacore::Double > >	_getFunction () const

Detailed Description

Describes a multiplet of Gaussian shaped spectral lines.

Intended use:

Public interface

Review Status

Date Reviewed:: yyyy/mm/dd
Test programs:: tSpectralFit

Prerequisite

SpectralElement module
CompiledSpectralElement module
CompiledSpectralElement module

Etymology

From Gaussian and multiplet and spectral line and element

Synopsis

The GaussianMultipletSpectralElement class describes a multiplet of Gaussian shaped spectral lines for describing spectral profile.

Relationships between Gaussians in the multiplet must be specified. Any combination of one or more of fixed relationships between line center offsets, line amplitude ratios, and/or line width ratios can be specified between a single reference line in the multiplet and other (non-reference) lines in the multiplet. The constructor takes a casacore::Vector of GaussianSpectralElements which describes the estimates of the n Gaussians in the multiplet. These objects themselves are not used in the fitting, but are used only to create the function that describes the multiplet. The first element in this casacore::Vector represents the reference line to which parameters of the other lines are constrained. In addition, the constructor takes an n-1 x 3 casacore::Matrix<casacore::Double> describing the fixed relationships between the reference line and the other lines in the multiplet. Each ith row describes the fixed relationship(s) between the (i+1)th and the zeroth (reference) Gaussian. The first element of each row describes the ratio of amplitudes between the (i+1)th and reference Gaussian, the second element describes the difference between the center locations of the (i+1)th and reference Gaussian, and the third represents the ratio of the FWHM of the (i+1)th and reference Gaussian. A value of 0 for any of these indicates there is no fixed relationship for that parameter. At least one value must be non-zero for each row and any combination of elements (including all of them) can be non-zero for any row in this matrix. The values of parameters of non-reference lines in the input vector that are constrained to the reference line are implicitly ignored and set in the constructor according to the specified constraint. If any of the parameters of the reference line are specified as fixed, the corresponding parameters of any non-reference lines which have the corresponding parameters constrained to the reference line are also implicitly fixed. Fixing a parameter in a non-reference line that is constrained to the corresponding parameter of the reference line that is not fixed will cause an exception.

Example

This is how to specify a doublet in which the only constraint is that the amplitudes between the lines must be fixed, the first Gaussian must have an ampliute of 0.6 times the zeroth (reference) Gaussian. Other than that, all other parameters can vary during the fit:

GaussianSpectralElement reference(5, 25, 16); The amplitude value of first is ignored because of the relationship to the reference, but it still must be specified in the constructor and must be non-zero or an exception will be thrown. GaussianSpectralElement first(1, 40, 17); casacore::Vector<GaussianSpectralElement> pair(2); pair[0] = reference; pair[1] = first; initialize constraints matrix to have nothing constrained (all values 0) casacore::Matrix<casacore::Double> fixedRel(1, 3, 0); Set the ratio of amplitudes between the first and reference (zeroth) line to be 0.6. fixedRel[0][0] = 0.6 GaussianMultipletSpectralElement doublet(pair,"",fixedRel);

Motivation

To allow specifying constraints between different Gaussian spectral lines for fitting, eg to support fitting of doublets.

Definition at line 120 of file GaussianMultipletSpectralElement.h.

Constructor & Destructor Documentation

casa::GaussianMultipletSpectralElement::GaussianMultipletSpectralElement	(	const std::vector< GaussianSpectralElement > &	estimates,
		const casacore::Matrix< casacore::Double > &	fixedRelationships
	)

Construct a Gaussian multiplet.

The values of non-reference (non-zeroth) estimates will be automatically adjusted if there is a fixed relationship between a non-reference Gaussian parameter and the corresponding reference Gaussian parameter.

casa::GaussianMultipletSpectralElement::GaussianMultipletSpectralElement ( const GaussianMultipletSpectralElement & other )

copy semantics

casa::GaussianMultipletSpectralElement::~GaussianMultipletSpectralElement ( )

Member Function Documentation

SpectralElement* casa::GaussianMultipletSpectralElement::clone ( ) const

virtual

Reimplemented from casa::CompiledSpectralElement.

void casa::GaussianMultipletSpectralElement::fix ( const casacore::Vector< casacore::Bool > & fix )

virtual

Set fixed parameters (true) or unset them (false)

Thrown Exceptions

casacore::AipsError if incorrect number of parameters (e.g. not 3 for GAUSSIAN)

Fix/unfix all in one go

Reimplemented from casa::SpectralElement.

const casacore::Matrix<casacore::Double>& casa::GaussianMultipletSpectralElement::getConstraints ( ) const

get the constraints matrix

const std::vector<GaussianSpectralElement>& casa::GaussianMultipletSpectralElement::getGaussians ( ) const

get the gaussians

GaussianMultipletSpectralElement& casa::GaussianMultipletSpectralElement::operator= ( const GaussianMultipletSpectralElement & other )

copy semantics

casacore::Bool casa::GaussianMultipletSpectralElement::operator== ( const GaussianMultipletSpectralElement & other ) const

void casa::GaussianMultipletSpectralElement::set ( const casacore::Vector< casacore::Double > & param )

virtual

These methods must be public because the architecture of the class hierarchy requires it and set() and setError() must be accessible by fitters.

However, it is strongly recommended that other classes not call these methods for object configuration but rather set them implicitly at construction via the casacore::Vector<GaussianSpectralElement> passed to the constructor.

Reimplemented from casa::SpectralElement.

void casa::GaussianMultipletSpectralElement::setError ( const casacore::Vector< casacore::Double > & err )

virtual

Set the error fields.

Reimplemented from casa::SpectralElement.

casacore::Bool casa::GaussianMultipletSpectralElement::toRecord ( casacore::RecordInterface & out ) const

virtual

Save to a record.

Reimplemented from casa::SpectralElement.