casacore::LELFunctionND< T > Class Template Reference

This LEL class handles functions with a variable number of arguments. More...

#include <LELFunction.h>

Public Member Functions
	LELFunctionND (const LELFunctionEnums::Function function, const Block< LatticeExprNode > &expr)
	Constructor takes operation and expressions to be operated upon. More...
	~LELFunctionND ()
	Destructor More...
virtual void	eval (LELArray< T > &result, const Slicer &section) const
	Recursively evaluate the expression More...
virtual LELScalar< T >	getScalar () const
	Recursively evaluate the scalar expression More...
virtual Bool	prepareScalarExpr ()
	Do further preparations (e.g. More...
virtual String	className () const
	Get class name. More...
virtual Bool	lock (FileLocker::LockType, uInt nattempts)
	Handle locking/syncing of a lattice in a lattice expression. More...
virtual void	unlock ()
virtual Bool	hasLock (FileLocker::LockType) const
virtual void	resync ()
Public Member Functions inherited from casacore::LELInterface< T >
virtual	~LELInterface ()
	Virtual destructor. More...
virtual void	evalRef (LELArrayRef< T > &result, const Slicer &section) const
LELArray< T >	getArray () const
	Get the result of an array subexpression. More...
Bool	isScalar () const
	Is the result of evaluating this expression a scalar ? More...
const IPosition &	shape () const
	Get the shape of the expression result. More...
const LELAttribute &	getAttribute () const
	Get expression attribute. More...

Private Attributes
LELFunctionEnums::Function	function_p
Block< LatticeExprNode >	arg_p

Additional Inherited Members
Static Public Member Functions inherited from casacore::LELInterface< T >
static Bool	replaceScalarExpr (CountedPtr< LELInterface< T > > &expr)
	If the given expression is a valid scalar, replace it by its result. More...
Protected Member Functions inherited from casacore::LELInterface< T >
void	setAttr (const LELAttribute &attrib)
	Set the expression attributes of this object. More...

Detailed Description

template<class T>
class casacore::LELFunctionND< T >

This LEL class handles functions with a variable number of arguments.

Intended use:

Internal

Review Status

Date Reviewed:

yyyy/mm/dd

Prerequisite

• Lattice
• LatticeExpr
• LatticeExprNode
• LELInterface
• LELFunctionEnums

Etymology

This derived LEL letter class handles numerical functions (arbitrary number of arguments) which return any data type

Synopsis

This templated LEL letter class is derived from LELInterface. It is used to construct LEL objects that apply functions of arbitrary number of arguments to Lattice expressions. They operate lattices with any type and return the same type. The available C++ function is iif with equivalents in the enum of IIF.

A description of the implementation details of the LEL classes can be found in Note 216

Example

Examples are not very useful as the user would never use these classes directly. Look in LatticeExprNode.cc to see how it invokes these classes. Examples of how the user would indirectly use this class (through the envelope) are:

IPosition shape(2,5,10);
ArrayLattice<Complex> w(shape); w.set(Complex(2.0,3.0));
ArrayLattice<Float> x(shape); x.set(0.05);
ArrayLattice<Float> y(shape); y.set(2.0);
ArrayLattice<Float> z(shape); y.set(2.0);
 
z.copyData(iif(x==0, y, x));

Copy x to z, but where x==0, take the correpsonding element from y. b

Motivation

An "if-then-else" like construction is very useful.

Definition at line 311 of file LELFunction.h.

Constructor & Destructor Documentation

LELFunctionND()

template<class T >

casacore::LELFunctionND< T >::LELFunctionND	(	const LELFunctionEnums::Function	function,
		const Block< LatticeExprNode > &	expr
	)

Constructor takes operation and expressions to be operated upon.

~LELFunctionND()

template<class T >

casacore::LELFunctionND< T >::~LELFunctionND

(

)

Destructor

Member Function Documentation

className()

template<class T >

virtual String casacore::LELFunctionND< T >::className ( ) const

virtual

Get class name.

Implements casacore::LELInterface< T >.

eval()

template<class T >

virtual void casacore::LELFunctionND< T >::eval ( LELArray< T > &  result, const Slicer &  section  ) const

virtual

Recursively evaluate the expression

Implements casacore::LELInterface< T >.

getScalar()

template<class T >

virtual LELScalar<T> casacore::LELFunctionND< T >::getScalar ( ) const

virtual

Recursively evaluate the scalar expression

Implements casacore::LELInterface< T >.

hasLock()

template<class T >

virtual Bool casacore::LELFunctionND< T >::hasLock ( FileLocker::LockType  ) const

virtual

Reimplemented from casacore::LELInterface< T >.

lock()

template<class T >

virtual Bool casacore::LELFunctionND< T >::lock ( FileLocker::LockType  , uInt  nattempts  )

virtual

Handle locking/syncing of a lattice in a lattice expression.

Reimplemented from casacore::LELInterface< T >.

prepareScalarExpr()

template<class T >

virtual Bool casacore::LELFunctionND< T >::prepareScalarExpr ( )

virtual

Do further preparations (e.g.

optimization) on the expression.

Implements casacore::LELInterface< T >.

resync()

template<class T >

virtual void casacore::LELFunctionND< T >::resync ( )

virtual

Reimplemented from casacore::LELInterface< T >.

unlock()

template<class T >

virtual void casacore::LELFunctionND< T >::unlock ( )

virtual

Reimplemented from casacore::LELInterface< T >.

Member Data Documentation

arg_p

template<class T >

Block<LatticeExprNode> casacore::LELFunctionND< T >::arg_p

private

Definition at line 348 of file LELFunction.h.

function_p

template<class T >

LELFunctionEnums::Function casacore::LELFunctionND< T >::function_p

private

Definition at line 347 of file LELFunction.h.

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

• lattices/LEL/LELFunction.h