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1 : //# PBMath1DIPoly.h: Definitions of 1-D Inverse casacore::Polynomial PBMath objects
2 : //# Copyright (C) 1996,1997,1998,2003
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 adressed 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 : //#
27 : //# $Id$
28 :
29 : #ifndef SYNTHESIS_PBMATH1DIPOLY_H
30 : #define SYNTHESIS_PBMATH1DIPOLY_H
31 :
32 : #include <casacore/casa/aips.h>
33 : #include <synthesis/TransformMachines/PBMath1D.h>
34 : #include <casacore/measures/Measures.h>
35 :
36 : namespace casa { //# NAMESPACE CASA - BEGIN
37 :
38 : //#forward
39 :
40 : // <summary>
41 : // PBMath1DIPoly is a 1-D Inverse casacore::Polynomial Expansion for a Primary Beam
42 : // </summary>
43 :
44 : // <use visibility=export>
45 :
46 : // <reviewed reviewer="" date="" tests="" demos="">
47 :
48 : // <prerequisite>
49 : // <li> <linkto class="PBMathInterface">PBMathInterface</linkto> class
50 : // <li> <linkto class="PBMath1D">PBMath1D</linkto> class
51 : // </prerequisite>
52 : //
53 : // <etymology>
54 : // PBMath1DIPoly: derived from PBMath1D, implements an Inverse casacore::Polynomial PB and VP
55 : // </etymology>
56 : //
57 : // <synopsis>
58 : // See PBMath1D for a general synopsis of the 1D PB types.
59 : //
60 : // VP(x) = sum_i coeff_i * x ^{2i},
61 : // out to maximumRadius (referenced to the reference frequency)
62 : //
63 : // x is in arcminutes, referenced to the reference frequency
64 : //
65 : // This move may make me a bit unpopular: since the PBMath1D constructors
66 : // construct a Voltage Pattern, the coeficienct for a polynomial type must
67 : // be in terms of the VP, not the PB. Hence, go back to the original PB
68 : // data, take the square root, and fit the same type polynomial to the
69 : // VP data.
70 : //
71 : // Inverse polynomial VP model: fit polynomial to 1/(VP_data).
72 : // Optionally, you can fit to 1/(VP_data) - 1, ignoring the constant
73 : // polynomial term so that the PB is constrained to be 1.0 at the beam
74 : // center.
75 : // </synopsis>
76 : //
77 : //
78 : // <example>
79 : // <srcblock>
80 : // coef(0) = 1.0; / VLA model
81 : // coef(1) = 7.22110e-04;
82 : // coef(2) = 1.21421e-07;
83 : // coef(3) = 9.68612e-11;
84 : // coef(4) = 1.86268e-13;
85 : // PBMath1DIPoly ipolyPB( coef, casacore::Quantity(43.0,"'"), casacore::Quantity(1.0,"GHz"));
86 : //
87 : // </srcblock>
88 : // </example>
89 : //
90 : // <motivation>
91 : // All of the 1-D PB types have everything in common except for the
92 : // details of their parameterization. This lightweight class
93 : // deals with those differences: construction, filling the PBArray
94 : // from construction parameters, and flushing to disk.
95 : // The inverse polynomial PB type is used for VLA and ATNF models.
96 : // </motivation>
97 : //
98 : // <todo asof="98/10/21">
99 : // <li> constructor from a casacore::MS beam subtable
100 : // <li> flush to casacore::MS beam subtable
101 : // </todo>
102 :
103 :
104 : class PBMath1DIPoly : public PBMath1D {
105 : public:
106 :
107 : PBMath1DIPoly() {};
108 :
109 : // Instantiation from arguments; default = no squint
110 : // squint is the offset from pointing center if the casacore::Stokes R beam
111 : // useSymmetricBeam forces a fit to the squinted beam
112 : PBMath1DIPoly(const casacore::Vector<casacore::Double>& coeff, casacore::Quantity maxRad,
113 : casacore::Quantity refFreq,
114 : casacore::Bool isThisVP=false,
115 : BeamSquint squint=BeamSquint(casacore::MDirection(casacore::Quantity(0.0, "deg"),
116 : casacore::Quantity(0.0, "deg"),
117 : casacore::MDirection::Ref(casacore::MDirection::AZEL)),
118 : casacore::Quantity(1.0, "GHz")),
119 : casacore::Bool useSymmetricBeam=false);
120 :
121 : // Instantiation from arguments; default = no squint
122 : // squint is the offset from pointing center if the casacore::Stokes R beam
123 : // useSymmetricBeam forces a fit to the squinted beam
124 : // Each column in coeff corresponds to a frequency in freqs
125 : PBMath1DIPoly(const casacore::Matrix<casacore::Double>& coeff, const casacore::Vector<casacore::Double>& freqs,
126 : casacore::Quantity maxRad,
127 : casacore::Quantity refFreq,
128 : casacore::Bool isThisVP=false,
129 : BeamSquint squint=BeamSquint(casacore::MDirection(casacore::Quantity(0.0, "deg"),
130 : casacore::Quantity(0.0, "deg"),
131 : casacore::MDirection::Ref(casacore::MDirection::AZEL)),
132 : casacore::Quantity(1.0, "GHz")),
133 : casacore::Bool useSymmetricBeam=false);
134 :
135 : // Instantiation from a row in the Beam subTable
136 : // PBMath1DIPoly(const casacore::Table& BeamSubTable, casacore::Int row,
137 : // casacore::Bool useSymmetricBeam=false);
138 :
139 : // Copy constructor
140 : // PBMath1DIPoly(const PBMath1DIPoly& other);
141 :
142 : // Assignment operator, by reference
143 : PBMath1DIPoly& operator=(const PBMath1DIPoly& other);
144 :
145 : // Clone the object
146 : // casacore::CountedPtr<PBMathInterface> clone();
147 :
148 :
149 : ~PBMath1DIPoly();
150 :
151 : // Get the type of PB this is
152 13 : PBMathInterface::PBClass whichPBClass() { return PBMathInterface::IPOLY; }
153 :
154 : // Flush the construction parameters to disk
155 : // casacore::Bool flushToTable(casacore::Table& beamSubTable, casacore::Int iRow);
156 :
157 : // Summarize the construction data for this primary beam
158 : void summary(casacore::Int nValues=0);
159 :
160 : protected:
161 :
162 : // Fill in vp_p array from construction parameters
163 : void fillPBArray();
164 :
165 : private:
166 :
167 : casacore::Vector<casacore::Double> coeff_p;
168 : casacore::Matrix<casacore::Double> wbcoeff_p;
169 :
170 : };
171 :
172 :
173 : } //# NAMESPACE CASA - END
174 :
175 : #endif
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