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GModelPar.hpp
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1 /***************************************************************************
2  * GModelPar.hpp - Model parameter class *
3  * ----------------------------------------------------------------------- *
4  * copyright (C) 2009-2014 by Juergen Knoedlseder *
5  * ----------------------------------------------------------------------- *
6  * *
7  * This program is free software: you can redistribute it and/or modify *
8  * it under the terms of the GNU General Public License as published by *
9  * the Free Software Foundation, either version 3 of the License, or *
10  * (at your option) any later version. *
11  * *
12  * This program is distributed in the hope that it will be useful, *
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of *
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
15  * GNU General Public License for more details. *
16  * *
17  * You should have received a copy of the GNU General Public License *
18  * along with this program. If not, see <http://www.gnu.org/licenses/>. *
19  * *
20  ***************************************************************************/
21 /**
22  * @file GModelPar.hpp
23  * @brief Model parameter class interface definition
24  * @author Juergen Knoedlseder
25  */
26 
27 #ifndef GMODELPAR_HPP
28 #define GMODELPAR_HPP
29 
30 /* __ Includes ___________________________________________________________ */
31 #include <string>
32 #include "GOptimizerPar.hpp"
33 #include "GXmlElement.hpp"
34 
35 
36 /***********************************************************************//**
37  * @class GModelPar
38  *
39  * @brief Model parameter class
40  *
41  * This class implements a model parameter. A model parameter is a numerical
42  * value that is used to describe a model. A model parameter has the
43  * following attributes:
44  * - @p value gives the numerical value of the parameter
45  * - @p error gives the statistical uncertainty in the parameter value
46  * - @p gradient gives the gradient of a the model with respect to the
47  * parameter
48  * - @p min gives the minimum value that the parameter value can take
49  * - @p max gives the maximum value that the parameter value can take
50  *
51  * The parameter attributes are set and retrieved using the value(),
52  * error(), gradient(), min() and max() methods, respectively. Furthermore,
53  * the range() method is used to simultaneously set the minimum and maximum
54  * value of a parameter.
55  *
56  * The minimum and maximum values are optional, and existence of these
57  * attributes is tested using the has_min() and has_max() methods,
58  * respectively. The minimum value, maximum value are removed using the
59  * remove_min() and remove_max() methods. Simultaneous removal of minimum
60  * and maximum values is done using the remove_range() method.
61  *
62  * Each parameter has furthermore the following properties:
63  * - @p free specifies whether the parameter should be fitted
64  * - @p grad specifies whether the parameter gradient is computed
65  * analytically (true) or numerically (false)
66  *
67  * The parameter property @p free is set using the free() and fix()
68  * methods and it is retrieved using the is_free() and is_fixed() methods.
69  * The attribute @p grad is set and retrieved using the has has_grad()
70  * methods.
71  *
72  * Each model parameter is factorized into a @p factor and a @p scale
73  * term. The GModelPar class stores the factors and the scale factor has
74  * data members, and the true values are computed using the following
75  * relations:
76  *
77  * value = m_factor_value * m_scale
78  * error = m_factor_error * m_scale
79  * gradient = m_factor_gradient * m_scale
80  * min = m_factor_min * m_scale
81  * max = m_factor_max * m_scale
82  *
83  * The @p factor and @p scale terms can be set and retrieved using the
84  * factor_value(), factor_error(), factor_gradient(), factor_min(),
85  * factor_max() and scale() methods.
86  ***************************************************************************/
87 class GModelPar : public GOptimizerPar {
88 
89 public:
90  // Constructors and destructors
91  GModelPar(void);
92  GModelPar(const std::string& name, const double& value);
93  GModelPar(const std::string& name, const double& factor,
94  const double& scale);
95  GModelPar(const GModelPar& par);
96  virtual ~GModelPar(void);
97 
98  // Operators
99  GModelPar& operator=(const GModelPar& par);
100 
101  // Methods
102  GModelPar* clone(void) const;
103  std::string classname(void) const;
104  void read(const GXmlElement& xml);
105  void write(GXmlElement& xml) const;
106 
107 protected:
108  // Protected methods
109  void init_members(void);
110  void copy_members(const GModelPar& par);
111  void free_members(void);
112 };
113 
114 
115 /***********************************************************************//**
116  * @brief Return class name
117  *
118  * @return String containing the class name ("GModelPar").
119  ***************************************************************************/
120 inline
121 std::string GModelPar::classname(void) const
122 {
123  return ("GModelPar");
124 }
125 
126 #endif /* GMODELPAR_HPP */
void init_members(void)
Initialise class members.
Definition: GModelPar.cpp:401
GModelPar * clone(void) const
Clone model parameter.
Definition: GModelPar.cpp:199
const std::string & name(void) const
Return parameter name.
XML element node class interface definition.
GModelPar(void)
Void constructor.
Definition: GModelPar.cpp:59
void write(GXmlElement &xml) const
Set or update parameter attributes in XML element.
Definition: GModelPar.cpp:353
XML element node class.
Definition: GXmlElement.hpp:47
void copy_members(const GModelPar &par)
Copy class members.
Definition: GModelPar.cpp:413
GModelPar & operator=(const GModelPar &par)
Assignment operator.
Definition: GModelPar.cpp:164
const double & scale(void) const
Return parameter scale.
Model parameter class.
Definition: GModelPar.hpp:87
virtual ~GModelPar(void)
Destructor.
Definition: GModelPar.cpp:142
void read(const GXmlElement &xml)
Extract parameter attributes from XML element.
Definition: GModelPar.cpp:229
double value(void) const
Return parameter value.
std::string classname(void) const
Return class name.
Definition: GModelPar.hpp:121
Optimizer parameter class interface definition.
void free_members(void)
Delete class members.
Definition: GModelPar.cpp:423
Optimizer parameter class.