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.
26//
27// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
28// By way of example, but not limitation, Licensor MAKES NO
29// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
30// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
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
47// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
48// GNU Lesser General Public License for more details.
49// You should have received a copy of the GNU Lesser General Public
50// License along with this program; if not, write to the Free Software
51// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301,
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
61namespace 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  */
71class 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