casacore
EpochUDF.h
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1//# EpochUDF.h: TaQL UDFs for Epoch conversions
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: 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 MEAS_EPOCHUDF_H
29#define MEAS_EPOCHUDF_H
30
31//# Includes
32#include <casacore/casa/aips.h>
33#include <casacore/meas/MeasUDF/EpochEngine.h>
34#include <casacore/meas/MeasUDF/PositionEngine.h>
35#include <casacore/tables/TaQL/UDFBase.h>
36
37namespace casacore {
38
39// <summary>
40// TaQL UDFs for Epoch conversions.
41// </summary>
42
43// <use visibility=export>
44
45// <reviewed reviewer="" date="" tests="tMeas.cc">
46// </reviewed>
47
48// <prerequisite>
49//# Classes you should understand before using this one.
50// <li> UDFBase
51// </prerequisite>
52
53// <synopsis>
54// EpochUDF defines UDFs (user defined functions) that can be used in TaQL
55// to convert Measures for epochs.
56// Special functions exist to convert to local sidereal time.
57// In this way such derived values appear to be ordinary TaQL functions.
58//
59// A function is called like:
60// <srcblock>
61// meas.epoch (toref, epoch, fromref, pos, posref)
62// For example,
63// meas.dir ('APP', 'MOON', POSITION, TIME)
64// </srcblock>
65// <ul>
66// <li>
67// <src>toref</src> is a single constant string.
68// <li>
69// <src>dir</src> can have various value types. A single numeric array is
70// a series of RA,DEC in J2000. If given as a set, the last argument of the
71// set can be the reference types of the values in the set. The values can
72// be strings (indicating planetary objects) or value pairs giving lon,lat.
73// The default reference type is J2000.
74// </ul>
75// All functions have data type double and unit radian.
76// </synopsis>
77
78// <motivation>
79// It makes it possible to handle measures in TaQL.
80// </motivation>
81
82 class EpochUDF: public UDFBase
83 {
84 public:
85 // Define the possible function types.
87
88 explicit EpochUDF (FuncType);
89
90 // Function to create an object.
91 static UDFBase* makeEPOCH (const String&);
92 static UDFBase* makeLAST (const String&);
93
94 // Setup the object.
95 virtual void setup (const Table&, const TaQLStyle&);
96
97 // Get the value.
98 virtual Double getDouble (const TableExprId& id);
100
101 private:
102 //# Data members.
107 Bool itsSidFrac; // T = use fraction for sidereal times
108 };
109
110} //end namespace
111
112#endif
FuncType
Define the possible function types.
Definition: EpochUDF.h:86
static UDFBase * makeLAST(const String &)
static UDFBase * makeEPOCH(const String &)
Function to create an object.
EpochEngine itsEngine
Definition: EpochUDF.h:103
virtual MArray< Double > getArrayDouble(const TableExprId &id)
PositionEngine itsPositionEngine
Definition: EpochUDF.h:104
virtual Double getDouble(const TableExprId &id)
Get the value.
virtual void setup(const Table &, const TaQLStyle &)
Setup the object.
MEpoch::Types itsRefType
Definition: EpochUDF.h:106
FuncType itsType
Definition: EpochUDF.h:105
Types
Types of known MEpochs Caution: The order defines the order in the translation matrix in the MCEpoch...
Definition: MEpoch.h:117
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
bool Bool
Define the standard types used by Casacore.
Definition: aipstype.h:42
double Double
Definition: aipstype.h:55