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LELConvert.h
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1//# LELConvert.h: Class to convert a LEL node from one numerical type to another
2//# Copyright (C) 1997,1998,1999,2000
3//# Associated Universities, Inc. Washington DC, USA.
4//#
5//# This library is free software; you can redistribute it and/or modify it
6//# under the terms of the GNU Library General Public License as published by
7//# the Free Software Foundation; either version 2 of the License, or (at your
8//# option) any later version.
9//#
10//# This library is distributed in the hope that it will be useful, but WITHOUT
11//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12//# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
13//# License for more details.
14//#
15//# You should have received a copy of the GNU Library General Public License
16//# along with this library; if not, write to the Free Software Foundation,
17//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
18//#
19//# Correspondence concerning AIPS++ should be addressed as follows:
20//# Internet email: aips2-request@nrao.edu.
21//# Postal address: AIPS++ Project Office
22//# National Radio Astronomy Observatory
23//# 520 Edgemont Road
24//# Charlottesville, VA 22903-2475 USA
25//#
26//# $Id$
27
28#ifndef LATTICES_LELCONVERT_H
29#define LATTICES_LELCONVERT_H
30
31
32//# Includes
33#include <casacore/casa/aips.h>
34#include <casacore/lattices/LEL/LELInterface.h>
35
36
37namespace casacore { //# NAMESPACE CASACORE - BEGIN
38
39// <summary>
40// Class to convert a LEL node from one numerical type to another
41// </summary>
42
43// <use visibility=local>
44
45// <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos="">
46// </reviewed>
47
48// <prerequisite>
49// <li> <linkto class="Lattice"> Lattice</linkto>
50// <li> <linkto class="LatticeExpr"> LatticeExpr</linkto>
51// <li> <linkto class="LatticeExprNode"> LatticeExprNode</linkto>
52// <li> <linkto class="LELInterface"> LELInterface</linkto>
53// </prerequisite>
54
55// <etymology>
56// This derived LEL letter class handles numerical type conversions
57// </etymology>
58
59// <synopsis>
60// This LEL letter class is derived from LELInterface. It
61// is used to construct LEL objects that know how to convert
62// between numerical types, such as Double to Float. They
63// operate on numerical Lattices and return a numerical Lattice.
64// The LELConvert object is embedded in the tree, and the conversion
65// actually happens at tree evaluation time.
66// <p>
67// A description of the implementation details of the LEL classes can
68// be found in
69// <a href="../notes/216.html">Note 216</a>
70// </synopsis>
71
72// <example>
73// Examples are not very useful as the user would never use
74// these classes directly. Look in LatticeExprNode.cc to see
75// how it invokes these classes. An example of how the user
76// would indirectly use this class (through the envelope) is:
77// <srcblock>
78// IPosition shape(2,5,10);
79// ArrayLattice<Float> x(shape); x.set(1.0);
80// ArrayLattice<Double> y(shape);
81// y.copyData(x); // y = x;
82// </srcblock>
83// The LELConvert class is embedded in the tree at construction time
84// so as to handle the conversion from Float to Double at evaluation time
85// </example>
86
87// <motivation>
88// We needed to be able to handle mixed types in the LEL classes
89// </motivation>
90
91//# <todo asof="1998/01/21">
92//# </todo>
93
94
95template <class T, class F> class LELConvert : public LELInterface<T>
96{
97public:
98
99// Constructor. <src><F></src> is the type we are coinverting from.
100// <src><T></src> is the type we are converting to.
102
103// Destructor does nothing
105
106// Recursively evaluate the expression.
107 virtual void eval (LELArray<T>& result,
108 const Slicer& section) const;
109
110// Recursively evaluate the scalar
111 virtual LELScalar<T> getScalar() const;
112
113// Do further preparations (e.g. optimization) on the expression.
115
116// Get class name
117 virtual String className() const;
118
119 // Handle locking/syncing of a lattice in a lattice expression.
120 // <group>
121 virtual Bool lock (FileLocker::LockType, uInt nattempts);
122 virtual void unlock();
124 virtual void resync();
125 // </group>
126
127private:
129};
130
131
132
133} //# NAMESPACE CASACORE - END
134
135#ifndef CASACORE_NO_AUTO_TEMPLATES
136#include <casacore/lattices/LEL/LELConvert.tcc>
137#endif //# CASACORE_NO_AUTO_TEMPLATES
138#endif
Referenced counted pointer for constant data.
Definition CountedPtr.h:81
LockType
Define the possible lock types.
Definition FileLocker.h:95
virtual String className() const
Get class name.
virtual void eval(LELArray< T > &result, const Slicer &section) const
Recursively evaluate the expression.
LELConvert(const CountedPtr< LELInterface< F > > &expr)
Constructor.
virtual void unlock()
virtual void resync()
virtual Bool lock(FileLocker::LockType, uInt nattempts)
Handle locking/syncing of a lattice in a lattice expression.
virtual Bool prepareScalarExpr()
Do further preparations (e.g.
virtual LELScalar< T > getScalar() const
Recursively evaluate the scalar.
CountedPtr< LELInterface< F > > pExpr_p
Definition LELConvert.h:128
~LELConvert()
Destructor does nothing.
virtual Bool hasLock(FileLocker::LockType) const
String: the storage and methods of handling collections of characters.
Definition String.h:225
this file contains all the compiler specific defines
Definition mainpage.dox:28
unsigned int uInt
Definition aipstype.h:51
bool Bool
Define the standard types used by Casacore.
Definition aipstype.h:42