00001 //# LELSpectralIndex.h: LEL function to calculate spectral index/ 00002 //# Copyright (C) 2001 00003 //# Associated Universities, Inc. Washington DC, USA. 00004 //# 00005 //# This library is free software; you can redistribute it and/or modify it 00006 //# under the terms of the GNU Library General Public License as published by 00007 //# the Free Software Foundation; either version 2 of the License, or (at your 00008 //# option) any later version. 00009 //# 00010 //# This library is distributed in the hope that it will be useful, but WITHOUT 00011 //# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 00012 //# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public 00013 //# License for more details. 00014 //# 00015 //# You should have received a copy of the GNU Library General Public License 00016 //# along with this library; if not, write to the Free Software Foundation, 00017 //# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA. 00018 //# 00019 //# Correspondence concerning AIPS++ should be addressed as follows: 00020 //# Internet email: aips2-request@nrao.edu. 00021 //# Postal address: AIPS++ Project Office 00022 //# National Radio Astronomy Observatory 00023 //# 520 Edgemont Road 00024 //# Charlottesville, VA 22903-2475 USA 00025 //# 00026 //# $Id$ 00027 00028 #ifndef LATTICES_LELSPECTRALINDEX_H 00029 #define LATTICES_LELSPECTRALINDEX_H 00030 00031 00032 //# Includes 00033 #include <casacore/casa/aips.h> 00034 #include <casacore/lattices/LEL/LELFunction.h> 00035 #include <casacore/casa/Containers/Block.h> 00036 00037 namespace casacore { //# NAMESPACE CASACORE - BEGIN 00038 00039 //# Forward Declarations 00040 00041 00042 // <summary> 00043 // This LEL class handles calculation of the spectral index. 00044 // </summary> 00045 00046 // <use visibility=local> 00047 00048 // <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos=""> 00049 // </reviewed> 00050 00051 // <prerequisite> 00052 // <li> <linkto class="Lattice"> Lattice</linkto> 00053 // <li> <linkto class="LatticeExpr"> LatticeExpr</linkto> 00054 // <li> <linkto class="LatticeExprNode"> LatticeExprNode</linkto> 00055 // <li> <linkto class="LELInterface"> LELInterface</linkto> 00056 // <li> <linkto class="LELFunctionEnums"> LELFunctionEnums</linkto> 00057 // </prerequisite> 00058 00059 // <synopsis> 00060 // This LEL letter class is derived from LELInterface. It is used to 00061 // construct LEL objects that calculate the sepectral index from 2 other 00062 // LEL expression (usually images). 00063 // It operates on real types (Float,Double) 00064 // </synopsis> 00065 00066 // <motivation> 00067 // This is a separate class (instead of being part of a LELFunction class), 00068 // because the calculation of the spectral index requires extra variables 00069 // (the frequencies) and some more complicated code. 00070 // </motivation> 00071 00072 template<class T> class LELSpectralIndex : public LELInterface<T> 00073 { 00074 //# Make members of parent class known. 00075 protected: 00076 using LELInterface<T>::setAttr; 00077 00078 public: 00079 // Constructor takes operation and expressions to be operated upon 00080 LELSpectralIndex (const Block<LatticeExprNode>& expr); 00081 00082 // Destructor 00083 ~LELSpectralIndex(); 00084 00085 // Recursively evaluate the expression 00086 virtual void eval (LELArray<T>& result, 00087 const Slicer& section) const; 00088 00089 // Get the result of a scalar subexpression. 00090 // Throws an exception as it is not possible. 00091 virtual LELScalar<T> getScalar() const; 00092 00093 // Do further preparations (e.g. optimization) on the expression. 00094 // Returns False. 00095 virtual Bool prepareScalarExpr(); 00096 00097 // Get class name 00098 virtual String className() const; 00099 00100 // Handle locking/syncing of a lattice in a lattice expression. 00101 // <group> 00102 virtual Bool lock (FileLocker::LockType, uInt nattempts); 00103 virtual void unlock(); 00104 virtual Bool hasLock (FileLocker::LockType) const; 00105 virtual void resync(); 00106 // </group> 00107 00108 private: 00109 Int itsFreqAxis; 00110 Block<Double> itsLogFreq; //# log(f0/f1) 00111 LatticeExprNode arg0_p; 00112 LatticeExprNode arg1_p; 00113 }; 00114 00115 00116 00117 } //# NAMESPACE CASACORE - END 00118 00119 #ifndef CASACORE_NO_AUTO_TEMPLATES 00120 #include <casacore/lattices/LEL/LELSpectralIndex.tcc> 00121 #endif //# CASACORE_NO_AUTO_TEMPLATES 00122 #endif