casa::QuantumHolder Class Reference

A holder for Quantums to enable record conversions. More...

#include <QuantumHolder.h>

Inheritance diagram for casa::QuantumHolder:

List of all members.

Public Member Functions
	QuantumHolder ()
	Creates an empty holder.
	QuantumHolder (const QBase &in)
	Create from a Quantum (copy semantics)
	QuantumHolder (const QuantumHolder &other)
	Copy a holder (copy semantics)
	~QuantumHolder ()
QuantumHolder &	operator= (const QuantumHolder &other)
	Assignment (copy semantics)
Bool	isEmpty () const
	Check if it holds a Quantity.
Bool	isQuantum () const
Bool	isScalar () const
Bool	isVector () const
Bool	isArray () const
Bool	isReal () const
Bool	isComplex () const
Bool	isQuantity () const
Bool	isQuantumDouble () const
Bool	isQuantumFloat () const
Bool	isQuantumInt () const
Bool	isQuantumComplex () const
Bool	isQuantumDComplex () const
Bool	isQuantumVectorDouble () const
Bool	isQuantumVectorFloat () const
Bool	isQuantumVectorInt () const
Bool	isQuantumVectorComplex () const
Bool	isQuantumVectorDComplex () const
Bool	isQuantumArrayDouble () const
Bool	isQuantumArrayFloat () const
Bool	isQuantumArrayInt () const
Bool	isQuantumArrayComplex () const
Bool	isQuantumArrayDComplex () const
Int	nelements () const
	Get number of numeric elements (1 if scalar, else vector length) or dimensions (0 if scalar)
Int	ndim () const
const QBase &	asQuantum () const
	Get a Quantum from the holder (with lifetime as long as holder exists).
const Quantum< Double > &	asQuantity ()
const Quantum< Double > &	asQuantumDouble ()
const Quantum< Float > &	asQuantumFloat ()
const Quantum< Int > &	asQuantumInt ()
const Quantum< Complex > &	asQuantumComplex ()
const Quantum< DComplex > &	asQuantumDComplex ()
const Quantum< Vector< Double > > &	asQuantumVectorDouble ()
const Quantum< Vector< Float > > &	asQuantumVectorFloat ()
const Quantum< Vector< Int > > &	asQuantumVectorInt ()
const Quantum< Vector< Complex > > &	asQuantumVectorComplex ()
const Quantum< Vector < DComplex > > &	asQuantumVectorDComplex ()
const Quantum< Array< Double > > &	asQuantumArrayDouble ()
const Quantum< Array< Float > > &	asQuantumArrayFloat ()
const Quantum< Array< Int > > &	asQuantumArrayInt ()
const Quantum< Array< Complex > > &	asQuantumArrayComplex ()
const Quantum< Array< DComplex > > &	asQuantumArrayDComplex ()
virtual Bool	fromRecord (String &error, const RecordInterface &in)
	Create a Quantum from a record or a string.
virtual Bool	fromString (String &error, const String &in)
	Initialise the class from a String representation.
virtual Bool	toRecord (String &error, RecordInterface &out) const
	Create a record from a Quantum.
virtual void	toRecord (RecordInterface &out) const
	this version throws an exception rather than returning false
virtual Record	toRecord () const
	this version throws an exception or returns the result Record.
virtual const String &	ident () const
	Return identification.
Private Member Functions
void	toReal (const uInt &tp)
	Convert to a different real scalar quantum.
void	toComplex (const uInt &tp)
	Convert to a different complex scalar quantum.
void	toVector ()
	Convert scalar to Vector.
void	toArray ()
	Convert scalar to Array.
Private Attributes
PtrHolder< QBase >	hold_p
	Pointer to a Quantity.

---

Detailed Description

A holder for Quantums to enable record conversions.

Intended use:

Public interface

 <h3>Review Status</h3><dl><dt>Reviewed By:<dd>UNKNOWN<dt>Date Reviewed:<dd>before2004/08/25<dt>Test programs:<dd>tQuantumHolder</dl> 

Prerequisite

• RecordInterface class
• Quantity class

Etymology

A Holder of general Quantums

Synopsis

This class can be used to handle a heterogeneous list of Quantums, and can handle toRecord() and fromRecord() conversions. A QuantumHolder is created empty, from a Quantum (e.g. a Quantum<Double>) or a Quantum<Vector<Float> >).

The accepted range of Quantums is:

• Quantum<Int>, Quantum<Float>, Quantum<Double> == Quantity
• Quantum<Complex>, Quantum<DComplex>
• Quantum<Vector<Int> >, Quantum<Vector<Float> >, Quantum<Vector<Double> >
• Quantum<Vector<Complex> >, Quantum<Vector<DComplex> >
• Quantum<Array<Int> >, Quantum<Array<Float> >, Quantum<Array<Double> >
• Quantum<Array<Complex> >, Quantum<Array<DComplex> >

Scalars in the same group can be converted to any in the same group (e.g. Int to Double); Vectors of length 1 can be converted to scalars in the corresponding group; Scalars can always be converted to Vectors in the corresponding group. Real scalar values can be converted to Complex values. Vectors cannot be converted to other type vectors.

Checks on the contents can be made with functions like isQuantity and the contents can be obtained with functions like asQuantity. It is an error to try and retrieve a Quantum of the wrong type and doing so will generate an exception (AipsError).

Example

        TableRecord rec;                // an empty record
        Quantity x(12.5, "km/s");       // a Quantity
        String error;                   // an error message
        if (!QuantumHolder(x).toRecord(error, rec)) {  // make record
                cout << error << endl;
        };
        Record grec;                    // a Record
        if (!QuantumHolder(x).toRecord(error, grec)) {  // make record
                cout << error << endl;
        };
    // Note that for GlishRecords use can be made of the
    // GlishRecord::to/fromrecord() methods.

Motivation

To make general conversions between Quantums and records, without knowing the actual Quantum being converted.

Definition at line 117 of file QuantumHolder.h.

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Constructor & Destructor Documentation

casa::QuantumHolder::QuantumHolder

(

)

Creates an empty holder.

casa::QuantumHolder::QuantumHolder

(

const QBase &

in

)

Create from a Quantum (copy semantics)

casa::QuantumHolder::QuantumHolder

(

const QuantumHolder &

other

)

Copy a holder (copy semantics)

casa::QuantumHolder::~QuantumHolder

(

)

---

Member Function Documentation

const Quantum<Double>& casa::QuantumHolder::asQuantity

(

)

const QBase& casa::QuantumHolder::asQuantum

(

)

const

Get a Quantum from the holder (with lifetime as long as holder exists).

Conversions done if necessary and as described in introduction.

Thrown Exceptions

• AipsError if holder empty or no conversion possible

const Quantum<Array<Complex> >& casa::QuantumHolder::asQuantumArrayComplex

(

)

const Quantum<Array<DComplex> >& casa::QuantumHolder::asQuantumArrayDComplex

(

)

const Quantum<Array<Double> >& casa::QuantumHolder::asQuantumArrayDouble

(

)

const Quantum<Array<Float> >& casa::QuantumHolder::asQuantumArrayFloat

(

)

const Quantum<Array<Int> >& casa::QuantumHolder::asQuantumArrayInt

(

)

const Quantum<Complex>& casa::QuantumHolder::asQuantumComplex

(

)

const Quantum<DComplex>& casa::QuantumHolder::asQuantumDComplex

(

)

const Quantum<Double>& casa::QuantumHolder::asQuantumDouble

(

)

const Quantum<Float>& casa::QuantumHolder::asQuantumFloat

(

)

const Quantum<Int>& casa::QuantumHolder::asQuantumInt

(

)

const Quantum<Vector<Complex> >& casa::QuantumHolder::asQuantumVectorComplex

(

)

const Quantum<Vector<DComplex> >& casa::QuantumHolder::asQuantumVectorDComplex

(

)

const Quantum<Vector<Double> >& casa::QuantumHolder::asQuantumVectorDouble

(

)

const Quantum<Vector<Float> >& casa::QuantumHolder::asQuantumVectorFloat

(

)

const Quantum<Vector<Int> >& casa::QuantumHolder::asQuantumVectorInt

(

)

virtual Bool casa::QuantumHolder::fromRecord	(	String &	error,
		const RecordInterface &	in
	)		[virtual]

Create a Quantum from a record or a string.

A valid record will contain the following fields:

• value: contains a numeric value of Int, Float, Double, Complex, DComplex or a vector thereof
• unit: a string with a valid unit string.

A valid string will be one of the special time/angle formats or a value with a valid unit string. Illegal values or units will return False and write an error message.

Implements casa::RecordTransformable.

virtual Bool casa::QuantumHolder::fromString	(	String &	error,
		const String &	inString
	)		[virtual]

Initialise the class from a String representation.

A string cannot contain enough information for many objects. Hence the default implementation of this class returns False, indicating that the class could not be initialised and an error message is appended to the supplied string. If the class can be initialised from a string then this function should be overridden.

Reimplemented from casa::RecordTransformable.

virtual const String& casa::QuantumHolder::ident

(

)

const [virtual]

Return identification.

Reimplemented from casa::RecordTransformable.

Bool casa::QuantumHolder::isArray

(

)

const

Bool casa::QuantumHolder::isComplex

(

)

const

Bool casa::QuantumHolder::isEmpty

(

)

const

Check if it holds a Quantity.

Note that a Vector of length 1 will give True to scalar questions.

Bool casa::QuantumHolder::isQuantity

(

)

const

Bool casa::QuantumHolder::isQuantum

(

)

const

Bool casa::QuantumHolder::isQuantumArrayComplex

(

)

const

Bool casa::QuantumHolder::isQuantumArrayDComplex

(

)

const

Bool casa::QuantumHolder::isQuantumArrayDouble

(

)

const

Bool casa::QuantumHolder::isQuantumArrayFloat

(

)

const

Bool casa::QuantumHolder::isQuantumArrayInt

(

)

const

Bool casa::QuantumHolder::isQuantumComplex

(

)

const

Bool casa::QuantumHolder::isQuantumDComplex

(

)

const

Bool casa::QuantumHolder::isQuantumDouble

(

)

const

Bool casa::QuantumHolder::isQuantumFloat

(

)

const

Bool casa::QuantumHolder::isQuantumInt

(

)

const

Bool casa::QuantumHolder::isQuantumVectorComplex

(

)

const

Bool casa::QuantumHolder::isQuantumVectorDComplex

(

)

const

Bool casa::QuantumHolder::isQuantumVectorDouble

(

)

const

Bool casa::QuantumHolder::isQuantumVectorFloat

(

)

const

Bool casa::QuantumHolder::isQuantumVectorInt

(

)

const

Bool casa::QuantumHolder::isReal

(

)

const

Bool casa::QuantumHolder::isScalar

(

)

const

Bool casa::QuantumHolder::isVector

(

)

const

Int casa::QuantumHolder::ndim

(

)

const

Int casa::QuantumHolder::nelements

(

)

const

Get number of numeric elements (1 if scalar, else vector length) or dimensions (0 if scalar)

Thrown Exceptions

• AipsError if holder empty

QuantumHolder& casa::QuantumHolder::operator=

(

const QuantumHolder &

other

)

Assignment (copy semantics)

void casa::QuantumHolder::toArray

(

)

[private]

Convert scalar to Array.

void casa::QuantumHolder::toComplex

(

const uInt &

tp

)

[private]

Convert to a different complex scalar quantum.

void casa::QuantumHolder::toReal

(

const uInt &

tp

)

[private]

Convert to a different real scalar quantum.

virtual Bool casa::QuantumHolder::toRecord	(	String &	error,
		RecordInterface &	out
	)		const [virtual]

Create a record from a Quantum.

A False return and an error message is only generated if there is no valid Quantum in the holder.

Implements casa::RecordTransformable.

virtual void casa::QuantumHolder::toRecord

(

RecordInterface &

out

)

const [virtual]

this version throws an exception rather than returning false

virtual Record casa::QuantumHolder::toRecord

(

)

const [virtual]

this version throws an exception or returns the result Record.

void casa::QuantumHolder::toVector

(

)

[private]

Convert scalar to Vector.

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Member Data Documentation

PtrHolder<QBase> casa::QuantumHolder::hold_p [private]

Pointer to a Quantity.

Definition at line 233 of file QuantumHolder.h.

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

• casacore/casa/Quanta/QuantumHolder.h