00001 //# LEL.h: Lattice expression 00002 //# Copyright (C) 1996,1997,1998,1999,2003 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: Lattices.h 21521 2014-12-10 08:06:42Z gervandiepen $ 00027 00028 #ifndef LATTICES_LEL_H 00029 #define LATTICES_LEL_H 00030 00031 00032 #include <casacore/lattices/LEL/LatticeExpr.h> 00033 00034 00035 namespace casacore { //# NAMESPACE CASACORE - BEGIN 00036 00037 // <module> 00038 00039 // <summary> 00040 // Lattice expressions. 00041 // </summary> 00042 00043 // <prerequisite> 00044 // <li> module <linkto module=Lattices>Lattices</linkto> 00045 // </prerequisite> 00046 00047 // <reviewed reviewer="Peter Barnes" date="1999/10/30" demos=""> 00048 // </reviewed> 00049 00050 // <etymology> 00051 // LEL: Lattice Expression Language. 00052 // </etymology> 00053 00054 // <synopsis> 00055 // A <linkto class=LatticeExpr>LatticeExpr</linkto> represents 00056 // a mathematical expression of lattices. All standard operators, regions, 00057 // and many, many <linkto class=LatticeExprNode>functions</linkto> 00058 // can be used in an expression. 00059 // <br> An expression is calculated on-the-fly. Thus only when 00060 // the user gets a part of the lattice, is the expression calculated 00061 // for that part. Subexpressions resulting in a scalar are calculated 00062 // only once, on a get of the first part of the lattice expression. 00063 // <br> Note that a lattice expression is not writable, thus using 00064 // the put function on such a lattice results in an exception. 00065 // <br> <a href="../notes/223.html">Note 223</a> 00066 // gives a more detailed 00067 // explanation of the capabilities of LEL (Lattice Expression Language). 00068 // <p> 00069 // If the expression consists of images, the result can also be 00070 // treated as an image using class <linkto class=ImageExpr>ImageExpr</linkto>. 00071 // With the <src>command</src> function in 00072 // <linkto class=ImageExprParse>ImageExprParse</linkto> it is possible 00073 // to parse and execute a LEL expression given as as a string. 00074 00075 // </module> 00076 00077 00078 } //# NAMESPACE CASACORE - END 00079 00080 #endif