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Public Member Functions | Private Attributes
casa::LELConvert< T, F > Class Template Reference

Class to convert a LEL node from one numerical type to another. More...

#include <LELConvert.h>

Inheritance diagram for casa::LELConvert< T, F >:
casa::LELInterface< T >

List of all members.

Public Member Functions

 LELConvert (const CountedPtr< LELInterface< F > > &expr)
 Constructor.
 ~LELConvert ()
 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.
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

CountedPtr< LELInterface< F > > pExpr_p
 
   


Detailed Description

template<class T, class F>
class casa::LELConvert< T, F >

Class to convert a LEL node from one numerical type to another.

Intended use:

Internal

Review Status

Date Reviewed:
yyyy/mm/dd

Prerequisite

Etymology

This derived LEL letter class handles numerical type conversions

Synopsis

This LEL letter class is derived from LELInterface. It is used to construct LEL objects that know how to convert between numerical types, such as Double to Float. They operate on numerical Lattices and return a numerical Lattice. The LELConvert object is embedded in the tree, and the conversion actually happens at tree evaluation time.

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<Double> y(shape); 
    y.copyData(x);                 // y = x;

The LELConvert class is embedded in the tree at construction time so as to handle the conversion from Float to Double at evaluation time

Motivation

We needed to be able to handle mixed types in the LEL classes

Definition at line 94 of file LELConvert.h.


Constructor & Destructor Documentation

template<class T , class F >
casa::LELConvert< T, F >::LELConvert ( const CountedPtr< LELInterface< F > > &  expr)

Constructor.

<F> is the type we are coinverting from. <T> is the type we are converting to.

template<class T , class F >
casa::LELConvert< T, F >::~LELConvert ( )

Destructor does nothing.


Member Function Documentation

template<class T , class F >
virtual String casa::LELConvert< T, F >::className ( ) const [virtual]

Get class name.

Implements casa::LELInterface< T >.

template<class T , class F >
virtual void casa::LELConvert< T, F >::eval ( LELArray< T > &  result,
const Slicer section 
) const [virtual]

Recursively evaluate the expression.

Implements casa::LELInterface< T >.

template<class T , class F >
virtual LELScalar<T> casa::LELConvert< T, F >::getScalar ( ) const [virtual]

Recursively evaluate the scalar.

Implements casa::LELInterface< T >.

template<class T , class F >
virtual Bool casa::LELConvert< T, F >::hasLock ( FileLocker::LockType  ) const [virtual]

Reimplemented from casa::LELInterface< T >.

template<class T , class F >
virtual Bool casa::LELConvert< T, F >::lock ( FileLocker::LockType  ,
uInt  nattempts 
) [virtual]

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

Reimplemented from casa::LELInterface< T >.

template<class T , class F >
virtual Bool casa::LELConvert< T, F >::prepareScalarExpr ( ) [virtual]

Do further preparations (e.g.

optimization) on the expression.

Implements casa::LELInterface< T >.

template<class T , class F >
virtual void casa::LELConvert< T, F >::resync ( ) [virtual]

Reimplemented from casa::LELInterface< T >.

template<class T , class F >
virtual void casa::LELConvert< T, F >::unlock ( ) [virtual]

Reimplemented from casa::LELInterface< T >.


Member Data Documentation

template<class T , class F >
CountedPtr<LELInterface<F> > casa::LELConvert< T, F >::pExpr_p [private]

   

Definition at line 127 of file LELConvert.h.


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