libMesh::TwostepTimeSolver Class Reference
#include <twostep_time_solver.h>
Detailed Description
This class wraps another UnsteadySolver derived class, and compares the results of timestepping with deltat and timestepping with 2*deltat to adjust future timestep lengths.
Currently this class only works on fully coupled Systems
This class is part of the new DifferentiableSystem framework, which is still experimental. Users of this framework should beware of bugs and future API changes.
Definition at line 52 of file twostep_time_solver.h.
Member Typedef Documentation
typedef std::map<std::string, std::pair<unsigned int, unsigned int> > libMesh::ReferenceCounter::Counts [protected, inherited] |
Data structure to log the information. The log is identified by the class name.
Definition at line 113 of file reference_counter.h.
The parent class
Reimplemented from libMesh::AdaptiveTimeSolver.
Definition at line 58 of file twostep_time_solver.h.
typedef DifferentiableSystem libMesh::TimeSolver::sys_type [inherited] |
The type of system
Reimplemented in libMesh::EigenTimeSolver, and libMesh::SteadySolver.
Definition at line 66 of file time_solver.h.
Constructor & Destructor Documentation
| libMesh::TwostepTimeSolver::TwostepTimeSolver | ( | sys_type & | s | ) | [explicit] |
Constructor. Requires a reference to the system to be solved.
Definition at line 29 of file twostep_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver, and libMesh::AutoPtr< Tp >::reset().
00030 : AdaptiveTimeSolver(s) 00031 00032 { 00033 // We start with a reasonable time solver: implicit Euler 00034 core_time_solver.reset(new EulerSolver(s)); 00035 }
| libMesh::TwostepTimeSolver::~TwostepTimeSolver | ( | ) |
Member Function Documentation
| void libMesh::UnsteadySolver::adjoint_advance_timestep | ( | ) | [virtual, inherited] |
This method advances the adjoint solution to the previous timestep, after an adjoint_solve() has been performed. This will be done before every UnsteadySolver::adjoint_solve().
Reimplemented from libMesh::TimeSolver.
Definition at line 169 of file unsteady_solver.C.
References libMesh::TimeSolver::_system, libMesh::DifferentiableSystem::deltat, libMesh::UnsteadySolver::first_adjoint_step, libMesh::System::get_dof_map(), libMesh::DofMap::get_send_list(), libMesh::System::get_vector(), libMesh::NumericVector< T >::localize(), libMesh::UnsteadySolver::old_local_nonlinear_solution, libMesh::TimeSolver::solution_history, and libMesh::System::time.
00170 { 00171 // On the first call of this function, we dont save the adjoint solution or 00172 // decrement the time, we just call the retrieve function below 00173 if(!first_adjoint_step) 00174 { 00175 // Call the store function to store the last adjoint before decrementing the time 00176 solution_history->store(); 00177 // Decrement the system time 00178 _system.time -= _system.deltat; 00179 } 00180 else 00181 { 00182 first_adjoint_step = false; 00183 } 00184 00185 // Retrieve the primal solution vectors at this time using the 00186 // solution_history object 00187 solution_history->retrieve(); 00188 00189 // Dont forget to localize the old_nonlinear_solution ! 00190 _system.get_vector("_old_nonlinear_solution").localize 00191 (*old_local_nonlinear_solution, 00192 _system.get_dof_map().get_send_list()); 00193 }
| void libMesh::AdaptiveTimeSolver::advance_timestep | ( | ) | [virtual, inherited] |
This method advances the solution to the next timestep, after a solve() has been performed. Often this will be done after every UnsteadySolver::solve(), but adaptive mesh refinement and/or adaptive time step selection may require some solve() steps to be repeated.
Reimplemented from libMesh::UnsteadySolver.
Definition at line 86 of file adaptive_time_solver.C.
References libMesh::TimeSolver::_system, libMesh::UnsteadySolver::first_solve, libMesh::System::get_vector(), libMesh::AdaptiveTimeSolver::last_deltat, libMesh::System::solution, and libMesh::System::time.
00087 { 00088 NumericVector<Number> &old_nonlinear_soln = 00089 _system.get_vector("_old_nonlinear_solution"); 00090 NumericVector<Number> &nonlinear_solution = 00091 *(_system.solution); 00092 // _system.get_vector("_nonlinear_solution"); 00093 00094 old_nonlinear_soln = nonlinear_solution; 00095 00096 if (!first_solve) 00097 _system.time += last_deltat; 00098 }
| virtual void libMesh::TimeSolver::before_timestep | ( | ) | [inline, virtual, inherited] |
This method is for subclasses or users to override to do arbitrary processing between timesteps
Definition at line 152 of file time_solver.h.
| Real libMesh::AdaptiveTimeSolver::calculate_norm | ( | System & | s, | |
| NumericVector< Number > & | v | |||
| ) | [protected, virtual, inherited] |
A helper function to calculate error norms
Definition at line 138 of file adaptive_time_solver.C.
References libMesh::System::calculate_norm(), and libMesh::AdaptiveTimeSolver::component_norm.
Referenced by solve().
00140 { 00141 return s.calculate_norm(v, component_norm); 00142 }
| AutoPtr< DiffSolver > & libMesh::AdaptiveTimeSolver::diff_solver | ( | ) | [virtual, inherited] |
An implicit linear or nonlinear solver to use at each timestep.
Reimplemented from libMesh::TimeSolver.
Definition at line 131 of file adaptive_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver.
00132 { 00133 return core_time_solver->diff_solver(); 00134 }
| void libMesh::ReferenceCounter::disable_print_counter_info | ( | ) | [static, inherited] |
Definition at line 106 of file reference_counter.C.
References libMesh::ReferenceCounter::_enable_print_counter.
00107 { 00108 _enable_print_counter = false; 00109 return; 00110 }
| Real libMesh::UnsteadySolver::du | ( | const SystemNorm & | norm | ) | const [virtual, inherited] |
Computes the size of ||u^{n+1} - u^{n}|| in some norm.
Note that, while you can always call this function, its result may or may not be very meaningful. For example, if you call this function right after calling advance_timestep() then you'll get a result of zero since old_nonlinear_solution is set equal to nonlinear_solution in this function.
Implements libMesh::TimeSolver.
Definition at line 218 of file unsteady_solver.C.
References libMesh::TimeSolver::_system, libMesh::System::calculate_norm(), libMesh::System::get_vector(), and libMesh::System::solution.
00219 { 00220 00221 AutoPtr<NumericVector<Number> > solution_copy = 00222 _system.solution->clone(); 00223 00224 solution_copy->add(-1., _system.get_vector("_old_nonlinear_solution")); 00225 00226 solution_copy->close(); 00227 00228 return _system.calculate_norm(*solution_copy, norm); 00229 }
| bool libMesh::AdaptiveTimeSolver::element_residual | ( | bool | get_jacobian, | |
| DiffContext & | context | |||
| ) | [virtual, inherited] |
This method is passed on to the core_time_solver
Implements libMesh::TimeSolver.
Definition at line 111 of file adaptive_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver, and libMesh::AutoPtr< Tp >::get().
00113 { 00114 libmesh_assert(core_time_solver.get()); 00115 00116 return core_time_solver->element_residual(request_jacobian, context); 00117 }
| void libMesh::ReferenceCounter::enable_print_counter_info | ( | ) | [static, inherited] |
Methods to enable/disable the reference counter output from print_info()
Definition at line 100 of file reference_counter.C.
References libMesh::ReferenceCounter::_enable_print_counter.
00101 { 00102 _enable_print_counter = true; 00103 return; 00104 }
| Real libMesh::AdaptiveTimeSolver::error_order | ( | ) | const [virtual, inherited] |
This method is passed on to the core_time_solver
Implements libMesh::UnsteadySolver.
Definition at line 102 of file adaptive_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver, and libMesh::AutoPtr< Tp >::get().
00103 { 00104 libmesh_assert(core_time_solver.get()); 00105 00106 return core_time_solver->error_order(); 00107 }
| std::string libMesh::ReferenceCounter::get_info | ( | ) | [static, inherited] |
Gets a string containing the reference information.
Definition at line 47 of file reference_counter.C.
References libMesh::ReferenceCounter::_counts, and libMesh::Quality::name().
Referenced by libMesh::ReferenceCounter::print_info().
00048 { 00049 #if defined(LIBMESH_ENABLE_REFERENCE_COUNTING) && defined(DEBUG) 00050 00051 std::ostringstream oss; 00052 00053 oss << '\n' 00054 << " ---------------------------------------------------------------------------- \n" 00055 << "| Reference count information |\n" 00056 << " ---------------------------------------------------------------------------- \n"; 00057 00058 for (Counts::iterator it = _counts.begin(); 00059 it != _counts.end(); ++it) 00060 { 00061 const std::string name(it->first); 00062 const unsigned int creations = it->second.first; 00063 const unsigned int destructions = it->second.second; 00064 00065 oss << "| " << name << " reference count information:\n" 00066 << "| Creations: " << creations << '\n' 00067 << "| Destructions: " << destructions << '\n'; 00068 } 00069 00070 oss << " ---------------------------------------------------------------------------- \n"; 00071 00072 return oss.str(); 00073 00074 #else 00075 00076 return ""; 00077 00078 #endif 00079 }
| void libMesh::ReferenceCounter::increment_constructor_count | ( | const std::string & | name | ) | [inline, protected, inherited] |
Increments the construction counter. Should be called in the constructor of any derived class that will be reference counted.
Definition at line 163 of file reference_counter.h.
References libMesh::ReferenceCounter::_counts, and libMesh::Threads::spin_mtx.
Referenced by libMesh::ReferenceCountedObject< RBParametrized >::ReferenceCountedObject().
00164 { 00165 Threads::spin_mutex::scoped_lock lock(Threads::spin_mtx); 00166 std::pair<unsigned int, unsigned int>& p = _counts[name]; 00167 00168 p.first++; 00169 }
| void libMesh::ReferenceCounter::increment_destructor_count | ( | const std::string & | name | ) | [inline, protected, inherited] |
Increments the destruction counter. Should be called in the destructor of any derived class that will be reference counted.
Definition at line 176 of file reference_counter.h.
References libMesh::ReferenceCounter::_counts, and libMesh::Threads::spin_mtx.
Referenced by libMesh::ReferenceCountedObject< RBParametrized >::~ReferenceCountedObject().
00177 { 00178 Threads::spin_mutex::scoped_lock lock(Threads::spin_mtx); 00179 std::pair<unsigned int, unsigned int>& p = _counts[name]; 00180 00181 p.second++; 00182 }
| void libMesh::AdaptiveTimeSolver::init | ( | ) | [virtual, inherited] |
The initialization function. This method is used to initialize internal data structures before a simulation begins.
Reimplemented from libMesh::UnsteadySolver.
Definition at line 57 of file adaptive_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver, libMesh::AutoPtr< Tp >::get(), and libMesh::UnsteadySolver::old_local_nonlinear_solution.
00058 { 00059 libmesh_assert(core_time_solver.get()); 00060 00061 // We override this because our core_time_solver is the one that 00062 // needs to handle new vectors, diff_solver->init(), etc 00063 core_time_solver->init(); 00064 00065 // As an UnsteadySolver, we have an old_local_nonlinear_solution, but it 00066 // isn't pointing to the right place - fix it 00067 // 00068 // This leaves us with two AutoPtrs holding the same pointer - dangerous 00069 // for future use. Replace with shared_ptr? 00070 old_local_nonlinear_solution = 00071 AutoPtr<NumericVector<Number> >(core_time_solver->old_local_nonlinear_solution.get()); 00072 }
| void libMesh::UnsteadySolver::init_data | ( | ) | [virtual, inherited] |
The data initialization function. This method is used to initialize internal data structures after the underlying System has been initialized
Reimplemented from libMesh::TimeSolver.
Definition at line 55 of file unsteady_solver.C.
References libMesh::TimeSolver::_system, libMesh::System::get_dof_map(), libMesh::DofMap::get_send_list(), libMeshEnums::GHOSTED, libMesh::System::n_dofs(), libMesh::System::n_local_dofs(), libMesh::UnsteadySolver::old_local_nonlinear_solution, and libMeshEnums::SERIAL.
00056 { 00057 #ifdef LIBMESH_ENABLE_GHOSTED 00058 old_local_nonlinear_solution->init (_system.n_dofs(), _system.n_local_dofs(), 00059 _system.get_dof_map().get_send_list(), false, 00060 GHOSTED); 00061 #else 00062 old_local_nonlinear_solution->init (_system.n_dofs(), false, SERIAL); 00063 #endif 00064 }
| bool libMesh::TimeSolver::is_adjoint | ( | ) | const [inline, inherited] |
Accessor for querying whether we need to do a primal or adjoint solve
Definition at line 217 of file time_solver.h.
References libMesh::TimeSolver::_is_adjoint.
Referenced by libMesh::FEMSystem::build_context().
00218 { return _is_adjoint; }
| virtual bool libMesh::UnsteadySolver::is_steady | ( | ) | const [inline, virtual, inherited] |
This is not a steady-state solver.
Implements libMesh::TimeSolver.
Definition at line 149 of file unsteady_solver.h.
| virtual AutoPtr<LinearSolver<Number> >& libMesh::TimeSolver::linear_solver | ( | ) | [inline, virtual, inherited] |
An implicit linear solver to use for adjoint and sensitivity problems.
Definition at line 172 of file time_solver.h.
References libMesh::TimeSolver::_linear_solver.
00172 { return _linear_solver; }
| static unsigned int libMesh::ReferenceCounter::n_objects | ( | ) | [inline, static, inherited] |
Prints the number of outstanding (created, but not yet destroyed) objects.
Definition at line 79 of file reference_counter.h.
References libMesh::ReferenceCounter::_n_objects.
00080 { return _n_objects; }
| Number libMesh::UnsteadySolver::old_nonlinear_solution | ( | const dof_id_type | global_dof_number | ) | const [inherited] |
- Returns:
- the old nonlinear solution for the specified global DOF.
Definition at line 207 of file unsteady_solver.C.
References libMesh::TimeSolver::_system, libMesh::System::get_dof_map(), libMesh::DofMap::n_dofs(), and libMesh::UnsteadySolver::old_local_nonlinear_solution.
Referenced by libMesh::EulerSolver::element_residual(), libMesh::Euler2Solver::element_residual(), libMesh::EulerSolver::side_residual(), and libMesh::Euler2Solver::side_residual().
00209 { 00210 libmesh_assert_less (global_dof_number, _system.get_dof_map().n_dofs()); 00211 libmesh_assert_less (global_dof_number, old_local_nonlinear_solution->size()); 00212 00213 return (*old_local_nonlinear_solution)(global_dof_number); 00214 }
| void libMesh::ReferenceCounter::print_info | ( | std::ostream & | out = libMesh::out |
) | [static, inherited] |
Prints the reference information, by default to libMesh::out.
Definition at line 88 of file reference_counter.C.
References libMesh::ReferenceCounter::_enable_print_counter, and libMesh::ReferenceCounter::get_info().
00089 { 00090 if( _enable_print_counter ) out_stream << ReferenceCounter::get_info(); 00091 }
| void libMesh::AdaptiveTimeSolver::reinit | ( | ) | [virtual, inherited] |
The reinitialization function. This method is used to resize internal data vectors after a mesh change.
Reimplemented from libMesh::UnsteadySolver.
Definition at line 76 of file adaptive_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver, and libMesh::AutoPtr< Tp >::get().
00077 { 00078 libmesh_assert(core_time_solver.get()); 00079 00080 // We override this because our core_time_solver is the one that 00081 // needs to handle new vectors, diff_solver->reinit(), etc 00082 core_time_solver->reinit(); 00083 }
| void libMesh::UnsteadySolver::retrieve_timestep | ( | ) | [virtual, inherited] |
This method retrieves all the stored solutions at the current system.time
Reimplemented from libMesh::TimeSolver.
Definition at line 195 of file unsteady_solver.C.
References libMesh::TimeSolver::_system, libMesh::System::get_dof_map(), libMesh::DofMap::get_send_list(), libMesh::System::get_vector(), libMesh::NumericVector< T >::localize(), libMesh::UnsteadySolver::old_local_nonlinear_solution, and libMesh::TimeSolver::solution_history.
00196 { 00197 // Retrieve all the stored vectors at the current time 00198 solution_history->retrieve(); 00199 00200 // Dont forget to localize the old_nonlinear_solution ! 00201 _system.get_vector("_old_nonlinear_solution").localize 00202 (*old_local_nonlinear_solution, 00203 _system.get_dof_map().get_send_list()); 00204 }
| void libMesh::TimeSolver::set_is_adjoint | ( | bool | _is_adjoint_value | ) | [inline, inherited] |
Accessor for setting whether we need to do a primal or adjoint solve
Definition at line 224 of file time_solver.h.
References libMesh::TimeSolver::_is_adjoint.
Referenced by libMesh::DifferentiableSystem::adjoint_solve(), libMesh::FEMSystem::postprocess(), and libMesh::DifferentiableSystem::solve().
00225 { _is_adjoint = _is_adjoint_value; }
| void libMesh::TimeSolver::set_solution_history | ( | const SolutionHistory & | _solution_history | ) | [inherited] |
A setter function users will employ if they need to do something other than save no solution history
Definition at line 91 of file time_solver.C.
References libMesh::SolutionHistory::clone(), and libMesh::TimeSolver::solution_history.
00092 { 00093 solution_history = _solution_history.clone(); 00094 }
| bool libMesh::AdaptiveTimeSolver::side_residual | ( | bool | get_jacobian, | |
| DiffContext & | context | |||
| ) | [virtual, inherited] |
This method is passed on to the core_time_solver
Implements libMesh::TimeSolver.
Definition at line 121 of file adaptive_time_solver.C.
References libMesh::AdaptiveTimeSolver::core_time_solver, and libMesh::AutoPtr< Tp >::get().
00123 { 00124 libmesh_assert(core_time_solver.get()); 00125 00126 return core_time_solver->side_residual(request_jacobian, context); 00127 }
| void libMesh::TwostepTimeSolver::solve | ( | ) | [virtual] |
This method solves for the solution at the next timestep. Usually we will only need to solve one (non)linear system per timestep, but more complex subclasses may override this.
Implements libMesh::AdaptiveTimeSolver.
Definition at line 45 of file twostep_time_solver.C.
References libMesh::TimeSolver::_system, libMesh::AdaptiveTimeSolver::calculate_norm(), libMesh::NumericVector< T >::clone(), libMesh::AdaptiveTimeSolver::core_time_solver, libMesh::DifferentiableSystem::deltat, libMesh::UnsteadySolver::first_solve, libMesh::AutoPtr< Tp >::get(), libMesh::System::get_vector(), libMesh::AdaptiveTimeSolver::global_tolerance, libMesh::AdaptiveTimeSolver::last_deltat, std::max(), libMesh::AdaptiveTimeSolver::max_deltat, libMesh::AdaptiveTimeSolver::max_growth, libMesh::AdaptiveTimeSolver::min_deltat, libMesh::out, std::pow(), libMesh::TimeSolver::quiet, libMesh::Real, libMesh::TimeSolver::reduce_deltat_on_diffsolver_failure, libMesh::System::solution, libMesh::AdaptiveTimeSolver::target_tolerance, libMesh::System::time, and libMesh::AdaptiveTimeSolver::upper_tolerance.
00046 { 00047 libmesh_assert(core_time_solver.get()); 00048 00049 // The core_time_solver will handle any first_solve actions 00050 first_solve = false; 00051 00052 // We may have to repeat timesteps entirely if our error is bad 00053 // enough 00054 bool max_tolerance_met = false; 00055 00056 // Calculating error values each time 00057 Real single_norm(0.), double_norm(0.), error_norm(0.), 00058 relative_error(0.); 00059 00060 while (!max_tolerance_met) 00061 { 00062 // If we've been asked to reduce deltat if necessary, make sure 00063 // the core timesolver does so 00064 core_time_solver->reduce_deltat_on_diffsolver_failure = 00065 this->reduce_deltat_on_diffsolver_failure; 00066 00067 if (!quiet) 00068 { 00069 libMesh::out << "\n === Computing adaptive timestep === " 00070 << std::endl; 00071 } 00072 00073 // Use the double-length timestep first (so the 00074 // old_nonlinear_solution won't have to change) 00075 core_time_solver->solve(); 00076 00077 // Save a copy of the double-length nonlinear solution 00078 // and the old nonlinear solution 00079 AutoPtr<NumericVector<Number> > double_solution = 00080 _system.solution->clone(); 00081 AutoPtr<NumericVector<Number> > old_solution = 00082 _system.get_vector("_old_nonlinear_solution").clone(); 00083 00084 double_norm = calculate_norm(_system, *double_solution); 00085 if (!quiet) 00086 { 00087 libMesh::out << "Double norm = " << double_norm << std::endl; 00088 } 00089 00090 // Then reset the initial guess for our single-length calcs 00091 *(_system.solution) = _system.get_vector("_old_nonlinear_solution"); 00092 00093 // Call two single-length timesteps 00094 // Be sure that the core_time_solver does not change the 00095 // timestep here. (This is unlikely because it just succeeded 00096 // with a timestep twice as large!) 00097 // FIXME: even if diffsolver failure is unlikely, we ought to 00098 // do *something* if it happens 00099 core_time_solver->reduce_deltat_on_diffsolver_failure = 0; 00100 00101 Real old_time = _system.time; 00102 Real old_deltat = _system.deltat; 00103 _system.deltat *= 0.5; 00104 core_time_solver->solve(); 00105 core_time_solver->advance_timestep(); 00106 core_time_solver->solve(); 00107 00108 single_norm = calculate_norm(_system, *_system.solution); 00109 if (!quiet) 00110 { 00111 libMesh::out << "Single norm = " << single_norm << std::endl; 00112 } 00113 00114 // Reset the core_time_solver's reduce_deltat... value. 00115 core_time_solver->reduce_deltat_on_diffsolver_failure = 00116 this->reduce_deltat_on_diffsolver_failure; 00117 00118 // But then back off just in case our advance_timestep() isn't 00119 // called. 00120 // FIXME: this probably doesn't work with multistep methods 00121 _system.get_vector("_old_nonlinear_solution") = *old_solution; 00122 _system.time = old_time; 00123 _system.deltat = old_deltat; 00124 00125 // Find the relative error 00126 *double_solution -= *(_system.solution); 00127 error_norm = calculate_norm(_system, *double_solution); 00128 relative_error = error_norm / _system.deltat / 00129 std::max(double_norm, single_norm); 00130 00131 // If the relative error makes no sense, we're done 00132 if (!double_norm && !single_norm) 00133 return; 00134 00135 if (!quiet) 00136 { 00137 libMesh::out << "Error norm = " << error_norm << std::endl; 00138 libMesh::out << "Local relative error = " 00139 << (error_norm / 00140 std::max(double_norm, single_norm)) 00141 << std::endl; 00142 libMesh::out << "Global relative error = " 00143 << (error_norm / _system.deltat / 00144 std::max(double_norm, single_norm)) 00145 << std::endl; 00146 libMesh::out << "old delta t = " << _system.deltat << std::endl; 00147 } 00148 00149 // If we haven't met our upper error tolerance, we'll have to 00150 // repeat this timestep entirely 00151 if (this->upper_tolerance && relative_error > this->upper_tolerance) 00152 { 00153 // Reset the initial guess for our next try 00154 *(_system.solution) = 00155 _system.get_vector("_old_nonlinear_solution"); 00156 00157 // Chop delta t in half 00158 _system.deltat /= 2.; 00159 00160 if (!quiet) 00161 { 00162 libMesh::out << "Failed to meet upper error tolerance" 00163 << std::endl; 00164 libMesh::out << "Retrying with delta t = " 00165 << _system.deltat << std::endl; 00166 } 00167 } 00168 else 00169 max_tolerance_met = true; 00170 } 00171 00172 00173 // Otherwise, compare the relative error to the tolerance 00174 // and adjust deltat 00175 last_deltat = _system.deltat; 00176 00177 const Real global_shrink_or_growth_factor = 00178 std::pow(this->target_tolerance / relative_error, 00179 static_cast<Real>(1. / core_time_solver->error_order())); 00180 00181 const Real local_shrink_or_growth_factor = 00182 std::pow(this->target_tolerance / 00183 (error_norm/std::max(double_norm, single_norm)), 00184 static_cast<Real>(1. / (core_time_solver->error_order()+1.))); 00185 00186 if (!quiet) 00187 { 00188 libMesh::out << "The global growth/shrink factor is: " 00189 << global_shrink_or_growth_factor << std::endl; 00190 libMesh::out << "The local growth/shrink factor is: " 00191 << local_shrink_or_growth_factor << std::endl; 00192 } 00193 00194 // The local s.o.g. factor is based on the expected **local** 00195 // truncation error for the timestepping method, the global 00196 // s.o.g. factor is based on the method's **global** truncation 00197 // error. You can shrink/grow the timestep to attempt to satisfy 00198 // either a global or local time-discretization error tolerance. 00199 00200 Real shrink_or_growth_factor = 00201 this->global_tolerance ? global_shrink_or_growth_factor : 00202 local_shrink_or_growth_factor; 00203 00204 if (this->max_growth && this->max_growth < shrink_or_growth_factor) 00205 { 00206 if (!quiet && this->global_tolerance) 00207 { 00208 libMesh::out << "delta t is constrained by max_growth" << std::endl; 00209 } 00210 shrink_or_growth_factor = this->max_growth; 00211 } 00212 00213 _system.deltat *= shrink_or_growth_factor; 00214 00215 // Restrict deltat to max-allowable value if necessary 00216 if ((this->max_deltat != 0.0) && (_system.deltat > this->max_deltat)) 00217 { 00218 if (!quiet) 00219 { 00220 libMesh::out << "delta t is constrained by maximum-allowable delta t." 00221 << std::endl; 00222 } 00223 _system.deltat = this->max_deltat; 00224 } 00225 00226 // Restrict deltat to min-allowable value if necessary 00227 if ((this->min_deltat != 0.0) && (_system.deltat < this->min_deltat)) 00228 { 00229 if (!quiet) 00230 { 00231 libMesh::out << "delta t is constrained by minimum-allowable delta t." 00232 << std::endl; 00233 } 00234 _system.deltat = this->min_deltat; 00235 } 00236 00237 if (!quiet) 00238 { 00239 libMesh::out << "new delta t = " << _system.deltat << std::endl; 00240 } 00241 }
| sys_type& libMesh::TimeSolver::system | ( | ) | [inline, inherited] |
- Returns:
- a writeable reference to the system we are solving.
Definition at line 162 of file time_solver.h.
References libMesh::TimeSolver::_system.
00162 { return _system; }
| const sys_type& libMesh::TimeSolver::system | ( | ) | const [inline, inherited] |
- Returns:
- a constant reference to the system we are solving.
Definition at line 157 of file time_solver.h.
References libMesh::TimeSolver::_system.
Referenced by libMesh::TimeSolver::reinit(), and libMesh::TimeSolver::solve().
00157 { return _system; }
Member Data Documentation
ReferenceCounter::Counts libMesh::ReferenceCounter::_counts [static, protected, inherited] |
Actually holds the data.
Definition at line 118 of file reference_counter.h.
Referenced by libMesh::ReferenceCounter::get_info(), libMesh::ReferenceCounter::increment_constructor_count(), and libMesh::ReferenceCounter::increment_destructor_count().
AutoPtr<DiffSolver> libMesh::TimeSolver::_diff_solver [protected, inherited] |
An implicit linear or nonlinear solver to use at each timestep.
Definition at line 232 of file time_solver.h.
Referenced by libMesh::TimeSolver::diff_solver(), libMesh::TimeSolver::init(), libMesh::TimeSolver::reinit(), libMesh::UnsteadySolver::solve(), and libMesh::TimeSolver::solve().
bool libMesh::ReferenceCounter::_enable_print_counter = true [static, protected, inherited] |
Flag to control whether reference count information is printed when print_info is called.
Definition at line 137 of file reference_counter.h.
Referenced by libMesh::ReferenceCounter::disable_print_counter_info(), libMesh::ReferenceCounter::enable_print_counter_info(), and libMesh::ReferenceCounter::print_info().
AutoPtr<LinearSolver<Number> > libMesh::TimeSolver::_linear_solver [protected, inherited] |
An implicit linear solver to use for adjoint problems.
Definition at line 237 of file time_solver.h.
Referenced by libMesh::TimeSolver::init(), libMesh::TimeSolver::linear_solver(), and libMesh::TimeSolver::reinit().
Threads::spin_mutex libMesh::ReferenceCounter::_mutex [static, protected, inherited] |
Mutual exclusion object to enable thread-safe reference counting.
Definition at line 131 of file reference_counter.h.
Threads::atomic< unsigned int > libMesh::ReferenceCounter::_n_objects [static, protected, inherited] |
The number of objects. Print the reference count information when the number returns to 0.
Definition at line 126 of file reference_counter.h.
Referenced by libMesh::ReferenceCounter::n_objects(), libMesh::ReferenceCounter::ReferenceCounter(), and libMesh::ReferenceCounter::~ReferenceCounter().
sys_type& libMesh::TimeSolver::_system [protected, inherited] |
A reference to the system we are solving.
Definition at line 242 of file time_solver.h.
Referenced by libMesh::UnsteadySolver::adjoint_advance_timestep(), libMesh::UnsteadySolver::advance_timestep(), libMesh::AdaptiveTimeSolver::advance_timestep(), libMesh::UnsteadySolver::du(), libMesh::SteadySolver::element_residual(), libMesh::EulerSolver::element_residual(), libMesh::Euler2Solver::element_residual(), libMesh::EigenTimeSolver::element_residual(), libMesh::UnsteadySolver::init(), libMesh::TimeSolver::init(), libMesh::EigenTimeSolver::init(), libMesh::UnsteadySolver::init_data(), libMesh::UnsteadySolver::old_nonlinear_solution(), libMesh::UnsteadySolver::reinit(), libMesh::UnsteadySolver::retrieve_timestep(), libMesh::SteadySolver::side_residual(), libMesh::EulerSolver::side_residual(), libMesh::Euler2Solver::side_residual(), libMesh::EigenTimeSolver::side_residual(), libMesh::UnsteadySolver::solve(), solve(), libMesh::EigenTimeSolver::solve(), and libMesh::TimeSolver::system().
Error calculations are done in this norm, DISCRETE_L2 by default.
Definition at line 109 of file adaptive_time_solver.h.
Referenced by libMesh::AdaptiveTimeSolver::calculate_norm().
std::vector<float> libMesh::AdaptiveTimeSolver::component_scale [inherited] |
If component_norms is non-empty, each variable's contribution to the error of a system will also be scaled by component_scale[var], unless component_scale is empty in which case all variables will be weighted equally.
Definition at line 117 of file adaptive_time_solver.h.
This object is used to take timesteps
Definition at line 104 of file adaptive_time_solver.h.
Referenced by libMesh::AdaptiveTimeSolver::diff_solver(), libMesh::AdaptiveTimeSolver::element_residual(), libMesh::AdaptiveTimeSolver::error_order(), libMesh::AdaptiveTimeSolver::init(), libMesh::AdaptiveTimeSolver::reinit(), libMesh::AdaptiveTimeSolver::side_residual(), solve(), and TwostepTimeSolver().
bool libMesh::UnsteadySolver::first_adjoint_step [protected, inherited] |
A bool that will be true the first time adjoint_advance_timestep() is called, (when the primal solution is to be used to set adjoint boundary conditions) and false thereafter
Definition at line 163 of file unsteady_solver.h.
Referenced by libMesh::UnsteadySolver::adjoint_advance_timestep().
bool libMesh::UnsteadySolver::first_solve [protected, inherited] |
A bool that will be true the first time solve() is called, and false thereafter
Reimplemented from libMesh::TimeSolver.
Definition at line 157 of file unsteady_solver.h.
Referenced by libMesh::UnsteadySolver::advance_timestep(), libMesh::AdaptiveTimeSolver::advance_timestep(), libMesh::UnsteadySolver::solve(), and solve().
bool libMesh::AdaptiveTimeSolver::global_tolerance [inherited] |
This flag, which is true by default, grows (shrinks) the timestep based on the expected global accuracy of the timestepping scheme. Global in this sense means the cumulative final-time accuracy of the scheme. For example, the backward Euler scheme's truncation error is locally of order 2, so that after N timesteps of size deltat, the result is first-order accurate. If you set this to false, you can grow (shrink) your timestep based on the local accuracy rather than the global accuracy of the core TimeSolver. Note that by setting this value to false you may fail to achieve the predicted convergence in time of the underlying method, however it may be possible to get more fine-grained control over step sizes as well.
Definition at line 173 of file adaptive_time_solver.h.
Referenced by solve().
Real libMesh::AdaptiveTimeSolver::last_deltat [protected, inherited] |
We need to store the value of the last deltat used, so that advance_timestep() will increment the system time correctly.
Definition at line 182 of file adaptive_time_solver.h.
Referenced by libMesh::AdaptiveTimeSolver::advance_timestep(), and solve().
Real libMesh::AdaptiveTimeSolver::max_deltat [inherited] |
Do not allow the adaptive time solver to select deltat > max_deltat. If you use the default max_deltat=0.0, then deltat is unlimited.
Definition at line 143 of file adaptive_time_solver.h.
Referenced by solve().
Real libMesh::AdaptiveTimeSolver::max_growth [inherited] |
Do not allow the adaptive time solver to select a new deltat greater than max_growth times the old deltat. If you use the default max_growth=0.0, then the deltat growth is unlimited.
Definition at line 157 of file adaptive_time_solver.h.
Referenced by solve().
Real libMesh::AdaptiveTimeSolver::min_deltat [inherited] |
Do not allow the adaptive time solver to select deltat < min_deltat. The default value is 0.0.
Definition at line 149 of file adaptive_time_solver.h.
Referenced by solve().
Serial vector of _system.get_vector("_old_nonlinear_solution")
Reimplemented from libMesh::TimeSolver.
Definition at line 133 of file unsteady_solver.h.
Referenced by libMesh::AdaptiveTimeSolver::AdaptiveTimeSolver(), libMesh::UnsteadySolver::adjoint_advance_timestep(), libMesh::UnsteadySolver::advance_timestep(), libMesh::AdaptiveTimeSolver::init(), libMesh::UnsteadySolver::init_data(), libMesh::UnsteadySolver::old_nonlinear_solution(), libMesh::UnsteadySolver::reinit(), libMesh::UnsteadySolver::retrieve_timestep(), and libMesh::AdaptiveTimeSolver::~AdaptiveTimeSolver().
bool libMesh::TimeSolver::quiet [inherited] |
Print extra debugging information if quiet == false.
Definition at line 177 of file time_solver.h.
Referenced by libMesh::UnsteadySolver::solve(), solve(), and libMesh::EigenTimeSolver::solve().
unsigned int libMesh::TimeSolver::reduce_deltat_on_diffsolver_failure [inherited] |
This value (which defaults to zero) is the number of times the TimeSolver is allowed to halve deltat and let the DiffSolver repeat the latest failed solve with a reduced timestep. Note that this has no effect for SteadySolvers. Note that you must set at least one of the DiffSolver flags "continue_after_max_iterations" or "continue_after_backtrack_failure" to allow the TimeSolver to retry the solve.
Definition at line 205 of file time_solver.h.
Referenced by libMesh::UnsteadySolver::solve(), and solve().
AutoPtr<SolutionHistory> libMesh::TimeSolver::solution_history [protected, inherited] |
An AutoPtr to a SolutionHistory object. Default is NoSolutionHistory, which the user can override by declaring a different kind of SolutionHistory in the application
Definition at line 260 of file time_solver.h.
Referenced by libMesh::UnsteadySolver::adjoint_advance_timestep(), libMesh::UnsteadySolver::advance_timestep(), libMesh::UnsteadySolver::retrieve_timestep(), and libMesh::TimeSolver::set_solution_history().
Real libMesh::AdaptiveTimeSolver::target_tolerance [inherited] |
This tolerance is the target relative error between double-deltat and single-deltat timesteps, scaled by deltat. If this error tolerance is exceeded or not met, future timesteps will be run with deltat shrunk or grown to compensate.
The default value is 1.0e-2; obviously users should select their own tolerance.
Definition at line 128 of file adaptive_time_solver.h.
Referenced by solve().
Real libMesh::AdaptiveTimeSolver::upper_tolerance [inherited] |
This tolerance is the maximum relative error between double-deltat and single-deltat timesteps, scaled by deltat. If this error tolerance is exceeded, the current timestep will be repeated with a smaller deltat.
If you use the default upper_tolerance=0.0,
Definition at line 137 of file adaptive_time_solver.h.
Referenced by solve().
The documentation for this class was generated from the following files:
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Last modified: February 05 2013 19:55:42 UTC
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