casacore::MFrequency Class Reference

A Measure: wave characteristics. More...

#include <MFrequency.h>

Inheritance diagram for casacore::MFrequency:

Public Types
enum	Types { REST, LSRK, LSRD, BARY, GEO, TOPO, GALACTO, LGROUP, CMB, N_Types, Undefined, N_Other, EXTRA, DEFAULT, LSR }
	Types of known MFrequencies Warning: The order defines the order in the translation matrix FromTo in the getConvert routine; Do not change the order without changing the array; Additions should be made before N_types, and an additional row and column should be coded in FromTo, and in showType(); . More...
typedef MVFrequency	MVType
	Measure value container for this class (i.e.
typedef MCFrequency	MCType
	Measure conversion routines for this class (i.e.
typedef MeasRef< MFrequency >	Ref
	Measure reference (i.e.
typedef MeasConvert< MFrequency >	Convert
	Measure conversion use (i.e.
typedef ScalarMeasColumn < MFrequency >	ScalarColumn
	Measure table Columns (e.g., MFrequency::ScalarColumn).
typedef ArrayMeasColumn < MFrequency >	ArrayColumn
Public Member Functions
typedef	WHATEVER_SUN_TYPEDEF (MFrequency) Types Types
	Reference enum Types (included originally for gcc 2.95).
	MFrequency ()
	Tip: In the following constructors and other functions, all MeasRef* can be replaced with simple `Measure::TYPE` where no offsets or frames are needed in the reference;* Default constructor; generates a zero rest frequency
	MFrequency (const MVFrequency &dt)
	Create from data and reference.
	MFrequency (const MVFrequency &dt, const MFrequency::Ref &rf)
	MFrequency (const MVFrequency &dt, MFrequency::Types rf)
	MFrequency (const Quantity &dt)
	MFrequency (const Quantity &dt, const MFrequency::Ref &rf)
	MFrequency (const Quantity &dt, MFrequency::Types rf)
	MFrequency (const Measure *dt)
	MFrequency (const MeasValue *dt)
virtual	~MFrequency ()
virtual const String &	tellMe () const
	Tell me your type.
virtual uInt	type () const
	Get the type (== Register() of derived Measure (faster than Strings) All should have: static uInt myType();.
Bool	giveMe (MFrequency::Ref &mr, const String &in)
virtual Bool	setOffset (const Measure &in)
	Set the offset in the reference (False if non-matching Measure).
virtual Bool	setRefString (const String &in)
	Set the reference type to the specified String.
virtual const String &	getDefaultType () const
	Get the default reference type.
virtual const String *	allTypes (Int &nall, Int &nextra, const uInt *&typ) const
	Get a list of all known reference codes.
virtual void	checkTypes () const
	Check if all internal tables of types (both enum and String) are complete and correct.
virtual String	getRefString () const
	Get the reference type (for records, including codes like R_).
Quantity	get (const Unit &un) const
	Get frequency in specified units.
MDoppler	toDoppler (const MVFrequency &rest)
	Make a Doppler velocity from the frequency and the specified rest frequency.
MDoppler	toDoppler (const MVFrequency &rest) const
MFrequency	toRest (const MDoppler &dop)
	Make a rest frequency using a Doppler velocity.
virtual Measure *	clone () const
	Make a copy.
Static Public Member Functions
static const String &	showMe ()
static void	assure (const Measure &in)
static MFrequency::Types	castType (uInt tp)
	Translate reference code.
static const String &	showType (MFrequency::Types tp)
static const String &	showType (uInt tp)
static Bool	getType (MFrequency::Types &tp, const String &in)
	Translate string to reference code.
static MFrequency::Types	typeFromString (const String &in)
	Throws an exception if the type string is not recognized.
static const String *	allMyTypes (Int &nall, Int &nextra, const uInt *&typ)
static void	checkMyTypes ()
static uInt	myType ()
	Get my type (as Register).
static MDoppler	toDoppler (const Measure &in, const MVFrequency &rest)
	Local use only.
static MFrequency	fromDoppler (const MDoppler &dop, const MVFrequency &rest)
	Make a frequency from the Doppler velocity and the specified rest frequency (default reference type LSRK).
static MFrequency	fromDoppler (const MDoppler &dop, const MVFrequency &rest, MFrequency::Types type)
static MFrequency	fromDoppler (const Measure &dop, const MVFrequency &rest, MFrequency::Types type)
	For internal use only.
static MFrequency	toRest (const Measure &in, const Measure &dop)
	For local use only.
Friends
class	MeasConvert< MFrequency >
	Conversion of data.

Detailed Description

A Measure: wave characteristics.

Intended use:

Public interface

Review Status

Reviewed By:: UNKNOWN
Date Reviewed:: before2004/08/25
Test programs:: tMeasure

Prerequisite

Measure class
MRadialVelocity class for some other background.

Etymology

Synopsis

MFrequency is a derived Measure class for wave characteristics.
An MFrequency can be generated from a simple value (or an MFrequency object), which is then interpreted as a frequency in Hz, and a reference, with an LSRK type as default.
It can also be generated from a Quantity, where the interpretation depends on the dimensionality of the Quantity:

time (e.g. s): period
frequency (e.g. Hz): frequency
angular frequency (e.g. arcmin/s): angular frequency
length (e.g. cm): wavelength
inverse length (e.g. mm^-1): wave number
energy (e.g. J.s): energy (i.e. h.nu)
momentum (e.g. kg.m): m.c/h

The different reference types of a frequency are:

MFrequency::REST -- Rest frequency
MFrequency::LSRD -- Local Standard of Rest (J2000) -- as the dynamical definition (IAU, [9,12,7] km/s in galactic coordinates)
MFrequency::LSRK -- LSR as a kinematical (radio) definition -- 20.0 km/s in direction ra,dec = [270,+30] deg (B1900.0)
MFrequency::BARY -- Barycentric (J2000)
MFrequency::GEO --- Geocentric
MFrequency::TOPO -- Topocentric
MFrequency::GALACTO -- Galacto centric (with rotation of 220 km/s in direction l,b = [90,0] deg.
MFrequency::LGROUP -- Local group velocity -- 308km/s towards l,b = [105,-7] deg (F. Ghigo)
MFrequency::CMB -- CMB velocity -- 369.5km/s towards l,b = [264.4, 48.4] deg (F. Ghigo)
MFrequency::DEFAULT = LSRK

Conversion between the different types is done with the standard MeasConvert class (MFrequency::Convert in this case). Some of the conversions are only possible if frame information has been filled in. The following frame information is necessary if a conversion goes to or from the (different) specified types:

Radial Velocity: REST
Epoch: TOPO, GEO
Position: TOPO
Direction all

To accommodate unknown or invalid frames, the additional reference type

MFrequency::Undefined

is available. Conversions to/from Undefined are not possible. If attempted, an exception will be thrown. The name was chosen to be Undefined and not UNDEFINED in order to not collide with the (ugly) WCSLIB macro of the upper case name and in concordance with Stokes::Undefined.
An MFrequency can be created from an MDoppler (and a rest frequency, (the QC class contains at least QC::HI)) by the fromDoppler() member. It can be converted to an MDoppler with the toDoppler(). Comparable methods will be available for MFrequency as toRadial() and fromRadial.
If the Doppler shift is known (e.g. from another spectral line), the REST frequency can be determined with the toREST() member.
Caution: Conversion between the different frequencies can, due to relativistic effects, only be done approximately for very high (order c) radial velocities (shifted frequencies); A better approach would be to start from radial velocities and a rest frequency;

Example

Get the Doppler shift for an oberved HI frequency of 1380 MHz

 cout << "Redshift for 1380 MHz: " <<
 MDoppler::Convert( MFrequency( Quantity(1380., "MHz"),
 MFrequency::TOPO).toDoppler(QC::HI),
 MDoppler::Z)() << endl;

Motivation

Definition at line 161 of file MFrequency.h.

Member Typedef Documentation

typedef ArrayMeasColumn<MFrequency> casacore::MFrequency::ArrayColumn

Definition at line 207 of file MFrequency.h.

typedef MeasConvert<MFrequency> casacore::MFrequency::Convert

Measure conversion use (i.e.

MFrequency::Convert)

Reimplemented from casacore::Measure.

Definition at line 204 of file MFrequency.h.

typedef MCFrequency casacore::MFrequency::MCType

Measure conversion routines for this class (i.e.

MFrequency::MCType)

Definition at line 200 of file MFrequency.h.

typedef MVFrequency casacore::MFrequency::MVType

Measure value container for this class (i.e.

MFrequency::MVType)

Definition at line 198 of file MFrequency.h.

typedef MeasRef<MFrequency> casacore::MFrequency::Ref

Measure reference (i.e.

MFrequency::Ref)

Definition at line 202 of file MFrequency.h.

typedef ScalarMeasColumn<MFrequency> casacore::MFrequency::ScalarColumn

Measure table Columns (e.g., MFrequency::ScalarColumn).

Definition at line 206 of file MFrequency.h.

Member Enumeration Documentation

enum casacore::MFrequency::Types

Types of known MFrequencies
Warning: The order defines the order in the translation matrix FromTo in the getConvert routine; Do not change the order without changing the array; Additions should be made before N_types, and an additional row and column should be coded in FromTo, and in showType();
.

Enumerator:

REST
LSRK
LSRD
BARY
GEO
TOPO
GALACTO
LGROUP
CMB
N_Types
Undefined
N_Other
EXTRA	all extra bits
DEFAULT	Defaults.
LSR	Synonyms.

Reimplemented from casacore::Measure.

Definition at line 176 of file MFrequency.h.

Constructor & Destructor Documentation

casacore::MFrequency::MFrequency ( )

Tip: In the following constructors and other functions, all MeasRef can be replaced with simple Measure::TYPE where no offsets or frames are needed in the reference;
Default constructor; generates a zero rest frequency

casacore::MFrequency::MFrequency ( const MVFrequency & dt )

Create from data and reference.

casacore::MFrequency::MFrequency	(	const MVFrequency &	dt,
		const MFrequency::Ref &	rf
	)

casacore::MFrequency::MFrequency	(	const MVFrequency &	dt,
		MFrequency::Types	rf
	)

casacore::MFrequency::MFrequency ( const Quantity & dt )

casacore::MFrequency::MFrequency	(	const Quantity &	dt,
		const MFrequency::Ref &	rf
	)

casacore::MFrequency::MFrequency	(	const Quantity &	dt,
		MFrequency::Types	rf
	)

casacore::MFrequency::MFrequency ( const Measure * dt )

casacore::MFrequency::MFrequency ( const MeasValue * dt )

virtual casacore::MFrequency::~MFrequency ( ) [virtual]

Member Function Documentation

static const String* casacore::MFrequency::allMyTypes	(	Int &	nall,
		Int &	nextra,
		const uInt *&	typ
	)			`[static]`

virtual const String* casacore::MFrequency::allTypes	(	Int &	nall,
		Int &	nextra,
		const uInt *&	typ
	)			const `[virtual]`

Get a list of all known reference codes.

nall returns the number in list, nextra the number of specials (like planets) that should be at end of list). typ returns the list of corresponding types.

Reimplemented from casacore::Measure.

static void casacore::MFrequency::assure ( const Measure & in ) [static]

static MFrequency::Types casacore::MFrequency::castType ( uInt tp ) [static]

Translate reference code.

The uInt version has a check for valid codes (i.e. it is a safe cast).

Thrown Exceptions

AipsError in the uInt interface if illegal code given

static void casacore::MFrequency::checkMyTypes ( ) [static]

virtual void casacore::MFrequency::checkTypes ( ) const [virtual]

Check if all internal tables of types (both enum and String) are complete and correct.

This function is called automatically if and when necessary.

Thrown Exceptions

AipsError if a (programming) error in the types.

Implements casacore::Measure.

virtual Measure* casacore::MFrequency::clone ( ) const [virtual]

Make a copy.

Implements casacore::Measure.

static MFrequency casacore::MFrequency::fromDoppler	(	const Measure &	dop,
		const MVFrequency &	rest,
		MFrequency::Types	type
	)			`[static]`

For internal use only.

static MFrequency casacore::MFrequency::fromDoppler	(	const MDoppler &	dop,
		const MVFrequency &	rest,
		MFrequency::Types	type
	)			`[static]`

static MFrequency casacore::MFrequency::fromDoppler	(	const MDoppler &	dop,
		const MVFrequency &	rest
	)			`[static]`

Make a frequency from the Doppler velocity and the specified rest frequency (default reference type LSRK).

Quantity casacore::MFrequency::get ( const Unit & un ) const

Get frequency in specified units.

virtual const String& casacore::MFrequency::getDefaultType ( ) const [virtual]

Get the default reference type.

Implements casacore::Measure.

virtual String casacore::MFrequency::getRefString ( ) const [virtual]

Get the reference type (for records, including codes like R_).

Implements casacore::Measure.

static Bool casacore::MFrequency::getType	(	MFrequency::Types &	tp,
		const String &	in
	)			`[static]`

Translate string to reference code.

Bool casacore::MFrequency::giveMe	(	MFrequency::Ref &	mr,
		const String &	in
	)

static uInt casacore::MFrequency::myType ( ) [static]

Get my type (as Register).

virtual Bool casacore::MFrequency::setOffset ( const Measure & in ) [virtual]

Set the offset in the reference (False if non-matching Measure).

virtual Bool casacore::MFrequency::setRefString ( const String & in ) [virtual]

Set the reference type to the specified String.

False if illegal string, reference set to DEFAULT.

Implements casacore::Measure.

static const String& casacore::MFrequency::showMe ( ) [static]

static const String& casacore::MFrequency::showType ( uInt tp ) [static]

static const String& casacore::MFrequency::showType ( MFrequency::Types tp ) [static]

virtual const String& casacore::MFrequency::tellMe ( ) const [virtual]

Tell me your type.

Implements casacore::Measure.

static MDoppler casacore::MFrequency::toDoppler	(	const Measure &	in,
		const MVFrequency &	rest
	)			`[static]`

Local use only.

MDoppler casacore::MFrequency::toDoppler ( const MVFrequency & rest ) const

MDoppler casacore::MFrequency::toDoppler ( const MVFrequency & rest )

Make a Doppler velocity from the frequency and the specified rest frequency.

static MFrequency casacore::MFrequency::toRest	(	const Measure &	in,
		const Measure &	dop
	)			`[static]`

For local use only.

MFrequency casacore::MFrequency::toRest ( const MDoppler & dop )

Make a rest frequency using a Doppler velocity.

virtual uInt casacore::MFrequency::type ( ) const [virtual]

Get the type (== Register() of derived Measure (faster than Strings) All should have: static uInt myType();.

Implements casacore::Measure.

static MFrequency::Types casacore::MFrequency::typeFromString ( const String & in ) [static]

Throws an exception if the type string is not recognized.

typedef casacore::MFrequency::WHATEVER_SUN_TYPEDEF ( MFrequency )

Reference enum Types (included originally for gcc 2.95).

Friends And Related Function Documentation

friend class MeasConvert< MFrequency > [friend]

Conversion of data.

Definition at line 166 of file MFrequency.h.

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

casacore/measures/Measures/MFrequency.h

casacore::MFrequency Class Reference

Public Types

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

Intended use:

Review Status

Prerequisite

Etymology

Synopsis

Example

Motivation

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Thrown Exceptions

Thrown Exceptions

Friends And Related Function Documentation