This LEL class handles numerical unary operators. More...

#include <LELUnary.h>

Inheritance diagram for casa::LELUnary< T >:

Public Member Functions
	LELUnary (const LELUnaryEnums::Operation op, const CountedPtr< LELInterface< T > > &pExpr)
	Constructor takes operation and expression to be operated upon.
	~LELUnary ()
	Destructor does nothing.
virtual void	eval (LELArray< T > &result, const Slicer &section) const
	Recursively evaluate the expression.
virtual LELScalar< T >	getScalar () const
	Recursively evaluate the scalar expression.
virtual Bool	prepareScalarExpr ()
	Do further preparations (e.g.
virtual String	className () const
	Get class name.
virtual Bool	lock (FileLocker::LockType, uInt nattempts)
	Handle locking/syncing of a lattice in a lattice expression.
virtual void	unlock ()
virtual Bool	hasLock (FileLocker::LockType) const
virtual void	resync ()
Private Attributes
LELUnaryEnums::Operation	op_p
CountedPtr< LELInterface< T > >	pExpr_p

Detailed Description

template<class T>
class casa::LELUnary< T >

This LEL class handles numerical unary operators.

Intended use:

Internal

Review Status

Date Reviewed:: yyyy/mm/dd

Prerequisite

Etymology

This derived LEL letter class handles numerical unary operators

Synopsis

This LEL letter class is derived from LELInterface. It is used to construct LEL objects that apply numerical unary operators to Lattice expressions. They operate on numerical Lattice (Float,Double,Complex,DComplex) expressions and return the same numerical type. The available C++ operators are +,- with equivalents in the enum of PLUS and MINUS.

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. An example of how the user would indirectly use this class (through the envelope) is:

    IPosition shape(2,5,10);
    ArrayLattice<Float> x(shape); x.set(1.0);
    ArrayLattice<Float> y(shape); 
    y.copyData(-x);                 // y = -x