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MeasUDF.h
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1//# MeasUDF.h: TaQL functions handling measures
2//# Copyright (C) 2011
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: casa-feedback@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#ifndef MEAS_MEASUDF_H
27#define MEAS_MEASUDF_H
28
29#include <casacore/casa/aips.h>
30#include <casacore/meas/MeasUDF/EpochUDF.h>
31
32namespace casacore { //# NAMESPACE CASACORE - BEGIN
33
34// <module>
35//
36// <summary>
37// TaQL user defined functions handling measures
38// </summary>
39
40// <prerequisite>
41// <li> UDFBase
42// <li> <linkto module="Measures:description">Measures</linkto> module
43// </prerequisite>
44//
45// <reviewed reviewer="" date="" demos="">
46// </reviewed>
47
48// <synopsis>
49// This module extends TaQL (the Table Query Language) with functions handling
50// measures. Currently it can handle MDirection, MEpoch, MPosition, MFrequency,
51// MRadialVelocity, MDoppler and MEarthMagnetic.
52//
53// These functions make it possible to convert one or more measures from
54// one reference type and frame to another. For example, to convert a
55// direction from J2000 to apparent one can specify the direction in J2000
56// as well as a time and position to define the measure frame like:
57// <srcblock>
58// calc meas.app ([4h23m32.7, 34d11m54.8], "J2000",
59// datetime(), "UTC", POSITION) from my.ms/ANTENNA
60// </srcblock>
61// The above example converts the given J2000 direction to apparent coordinates
62// for the given time (current time is used) and for all positions in the
63// POSITION column in the given ANTENNA table.
64//
65// As shown in the example an argument of a <src>meas</src> function can be
66// a constant, a table column in a table. or any expression.
67// If a table column is given, it is recognized if the column has a reference
68// type attached to it (using the TableMeasures). In this example it
69// would be recognized that the positions in the POSITION column are given
70// as, say, WGS84.
71// <br>For constants the reference type can be given in case it differs from
72// the default type. In the example UTC is specified for the time (was not
73// necessary because it is the default).
74
75// <note>
76// The meas library will be loaded dynamically by TaQL when such a function
77// is used. Therefore it is important that the library and the other casacore
78// libraries are built shared.
79// <br>It is also important that the library can be found in the
80// (DY)LD_LIBRARY_PATH.
81// </note>
82// </synopsis>
83//
84// <motivation>
85// It is very handy to be able to convert measures in tools that
86// deal with various table columns (e.g. TaQL, TablePlot, pyrap).
87// </motivation>
88
89//# <todo asof="1997/02/01">
90//# </todo>
91
92// </module>
93
94
95} //# NAMESPACE CASACORE - END
96
97#endif
this file contains all the compiler specific defines
Definition mainpage.dox:28