// $Id: linear_implicit_system.h 2501 2007-11-20 02:33:29Z benkirk $// The libMesh Finite Element Library.// Copyright (C) 2002-2007  Benjamin S. Kirk, John W. Peterson  // This library is free software; you can redistribute it and/or// modify it under the terms of the GNU Lesser General Public// License as published by the Free Software Foundation; either// version 2.1 of the License, or (at your option) any later version.  // This library is distributed in the hope that it will be useful,// but WITHOUT ANY WARRANTY; without even the implied warranty of// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU// Lesser General Public License for more details.  // You should have received a copy of the GNU Lesser General Public// License along with this library; if not, write to the Free Software// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA#ifndef __linear_implicit_system_h__#define __linear_implicit_system_h__// C++ includes// Local Includes#include "implicit_system.h"// Forward Declarationstemplate <typename T> class LinearSolver;/** * This class provides a specific system class.  It aims * at implicit systems, offering nothing more than just * the essentials needed to solve a system.  Note * that still additional vectors/matrices may be added, * as offered in the parent class \p ExplicitSystem. */// ------------------------------------------------------------// LinearImplicitSystem class definitionclass LinearImplicitSystem : public ImplicitSystem{public:  /**   * Constructor.  Optionally initializes required   * data structures.   */  LinearImplicitSystem (EquationSystems& es,			const std::string& name,			const unsigned int number);  /**   * Destructor.   */  virtual ~LinearImplicitSystem ();  /**   * The type of system.   */  typedef LinearImplicitSystem sys_type;  /**   * The type of the parent.   */  typedef ImplicitSystem Parent;    /**   * @returns a clever pointer to the system.   */  sys_type & system () { return *this; }    /**   * Clear all the data structures associated with   * the system.    */  virtual void clear ();  /**   * Reinitializes the member data fields associated with   * the system, so that, e.g., \p assemble() may be used.   */  virtual void reinit ();   //   /**//    * Prepares \p matrix and \p _dof_map for matrix assembly.//    * Does not actually assemble anything.  For matrix assembly,//    * use the \p assemble() in derived classes.//    * @e Should be overloaded in derived classes.//    *///   virtual void assemble () { ImplicitSystem::assemble(); }   /**   * Assembles & solves the linear system Ax=b.    */  virtual void solve ();   /**   * @returns \p "LinearImplicit".  Helps in identifying   * the system type in an equation system file.   */  virtual std::string system_type () const { return "LinearImplicit"; }  /**   * The \p LinearSolver defines the interface used to   * solve the linear_implicit system.  This class handles all the   * details of interfacing with various linear algebra packages   * like PETSc or LASPACK.   */  AutoPtr<LinearSolver<Number> > linear_solver;    /**   * Returns  the number of iterations    * taken for the most recent linear solve.   */  unsigned int n_linear_iterations() const { return _n_linear_iterations; }  /**   * Returns the final residual for the linear system solve.   */  Real final_linear_residual() const { return _final_linear_residual; }  protected:    /**   * The number of linear iterations required to solve the linear   * system Ax=b.   */  unsigned int _n_linear_iterations;  /**   * The final residual for the linear system Ax=b.   */  Real _final_linear_residual;};// ------------------------------------------------------------// LinearImplicitSystem inline methods#endif