1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008-2009 Gael Guennebaud <gael.guennebaud@inria.fr>
5 
6 /* NOTE The class IterationController has been adapted from the iteration
7  *      class of the GMM++ and ITL libraries.
8  */
9 
10 //=======================================================================
11 // Copyright (C) 1997-2001
12 // Authors: Andrew Lumsdaine <lums@osl.iu.edu>
13 //          Lie-Quan Lee     <llee@osl.iu.edu>
14 //
15 // This file is part of the Iterative Template Library
16 //
17 // You should have received a copy of the License Agreement for the
18 // Iterative Template Library along with the software;  see the
19 // file LICENSE.
20 //
21 // Permission to modify the code and to distribute modified code is
22 // granted, provided the text of this NOTICE is retained, a notice that
23 // the code was modified is included with the above COPYRIGHT NOTICE and
24 // with the COPYRIGHT NOTICE in the LICENSE file, and that the LICENSE
25 // file is distributed with the modified code.
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31 // OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
32 // OR OTHER RIGHTS.
33 //=======================================================================
34 
35 //========================================================================
36 //
37 // Copyright (C) 2002-2007 Yves Renard
38 //
39 // This file is a part of GETFEM++
40 //
41 // Getfem++ is free software; you can redistribute it and/or modify
42 // it under the terms of the GNU Lesser General Public License as
43 // published by the Free Software Foundation; version 2.1 of the License.
44 //
45 // This program is distributed in the hope that it will be useful,
46 // but WITHOUT ANY WARRANTY; without even the implied warranty of
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48 // GNU Lesser General Public License for more details.
49 // You should have received a copy of the GNU Lesser General Public
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52 // USA.
53 //
54 //========================================================================
55 
56 #include "../../../../Eigen/src/Core/util/NonMPL2.h"
57 
58 #ifndef EIGEN_ITERATION_CONTROLLER_H
59 #define EIGEN_ITERATION_CONTROLLER_H
60 
61 namespace Eigen {
62 
63 /** \ingroup IterativeSolvers_Module
64   * \class IterationController
65   *
66   * \brief Controls the iterations of the iterative solvers
67   *
68   * This class has been adapted from the iteration class of GMM++ and ITL libraries.
69   *
70   */
71 class IterationController
72 {
73   protected :
74     double m_rhsn;        ///< Right hand side norm
75     size_t m_maxiter;     ///< Max. number of iterations
76     int m_noise;          ///< if noise > 0 iterations are printed
77     double m_resmax;      ///< maximum residual
78     double m_resminreach, m_resadd;
79     size_t m_nit;         ///< iteration number
80     double m_res;         ///< last computed residual
81     bool m_written;
82     void (*m_callback)(const IterationController&);
83   public :
84 
85     void init()
86     {
87       m_nit = 0; m_res = 0.0; m_written = false;
88       m_resminreach = 1E50; m_resadd = 0.0;
89       m_callback = 0;
90     }
91 
92     IterationController(double r = 1.0E-8, int noi = 0, size_t mit = size_t(-1))
93       : m_rhsn(1.0), m_maxiter(mit), m_noise(noi), m_resmax(r) { init(); }
94 
95     void operator ++(int) { m_nit++; m_written = false; m_resadd += m_res; }
96     void operator ++() { (*this)++; }
97 
98     bool first() { return m_nit == 0; }
99 
100     /* get/set the "noisyness" (verbosity) of the solvers */
101     int noiseLevel() const { return m_noise; }
102     void setNoiseLevel(int n) { m_noise = n; }
103     void reduceNoiseLevel() { if (m_noise > 0) m_noise--; }
104 
105     double maxResidual() const { return m_resmax; }
106     void setMaxResidual(double r) { m_resmax = r; }
107 
108     double residual() const { return m_res; }
109 
110     /* change the user-definable callback, called after each iteration */
111     void setCallback(void (*t)(const IterationController&))
112     {
113       m_callback = t;
114     }
115 
116     size_t iteration() const { return m_nit; }
117     void setIteration(size_t i) { m_nit = i; }
118 
119     size_t maxIterarions() const { return m_maxiter; }
120     void setMaxIterations(size_t i) { m_maxiter = i; }
121 
122     double rhsNorm() const { return m_rhsn; }
123     void setRhsNorm(double r) { m_rhsn = r; }
124 
125     bool converged() const { return m_res <= m_rhsn * m_resmax; }
126     bool converged(double nr)
127     {
128       using std::abs;
129       m_res = abs(nr);
130       m_resminreach = (std::min)(m_resminreach, m_res);
131       return converged();
132     }
133     template<typename VectorType> bool converged(const VectorType &v)
134     { return converged(v.squaredNorm()); }
135 
136     bool finished(double nr)
137     {
138       if (m_callback) m_callback(*this);
139       if (m_noise > 0 && !m_written)
140       {
141         converged(nr);
142         m_written = true;
143       }
144       return (m_nit >= m_maxiter || converged(nr));
145     }
146     template <typename VectorType>
147     bool finished(const MatrixBase<VectorType> &v)
148     { return finished(double(v.squaredNorm())); }
149 
150 };
151 
152 } // end namespace Eigen
153 
154 #endif // EIGEN_ITERATION_CONTROLLER_H
155