LELConvert.h
Classes
- LELConvert -- Class to convert a LEL node from one numerical type to another (full description)
template <class T, class F> class LELConvert : public LELInterface<T>
Interface
- Public Members
- LELConvert (const CountedPtr<LELInterface<F> >& expr)
- ~LELConvert()
- virtual void eval (LELArray<T>& result, const Slicer& section) const
- virtual LELScalar<T> getScalar() const
- virtual Bool prepareScalarExpr()
- virtual String className() const
- virtual Bool lock (FileLocker::LockType, uInt nattempts)
- virtual void unlock()
- virtual Bool hasLock (FileLocker::LockType) const
- virtual void resync()
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
Member Description
Constructor. <F> is the type we are coinverting from.
<T> is the type we are converting to.
Destructor does nothing
virtual void eval (LELArray<T>& result, const Slicer& section) const
Recursively evaluate the expression.
Recursively evaluate the scalar
Do further preparations (e.g. optimization) on the expression.
Get class name
virtual Bool lock (FileLocker::LockType, uInt nattempts)
virtual void unlock()
virtual Bool hasLock (FileLocker::LockType) const
virtual void resync()
Handle locking/syncing of a lattice in a lattice expression.