libMesh::TwostepTimeSolver Class Reference

#include <twostep_time_solver.h>

Inheritance diagram for libMesh::TwostepTimeSolver:

Public Types

typedef AdaptiveTimeSolver Parent
 
typedef DifferentiableSystem sys_type
 

Public Member Functions

 TwostepTimeSolver (sys_type &s)
 
 ~TwostepTimeSolver ()
 
virtual void solve () override
 
virtual void init () override
 
virtual void reinit () override
 
virtual void advance_timestep () override
 
virtual Real error_order () const override
 
virtual bool element_residual (bool get_jacobian, DiffContext &) override
 
virtual bool side_residual (bool get_jacobian, DiffContext &) override
 
virtual bool nonlocal_residual (bool get_jacobian, DiffContext &) override
 
virtual std::unique_ptr< DiffSolver > & diff_solver () override
 
virtual std::unique_ptr< LinearSolver< Number > > & linear_solver () override
 
virtual unsigned int time_order () const override
 
virtual void init_data () override
 
virtual void adjoint_advance_timestep () override
 
virtual void retrieve_timestep () override
 
Number old_nonlinear_solution (const dof_id_type global_dof_number) const
 
virtual Real du (const SystemNorm &norm) const override
 
virtual bool is_steady () const override
 
virtual void before_timestep ()
 
const sys_typesystem () const
 
sys_typesystem ()
 
void set_solution_history (const SolutionHistory &_solution_history)
 
bool is_adjoint () const
 
void set_is_adjoint (bool _is_adjoint_value)
 

Static Public Member Functions

static std::string get_info ()
 
static void print_info (std::ostream &out=libMesh::out)
 
static unsigned int n_objects ()
 
static void enable_print_counter_info ()
 
static void disable_print_counter_info ()
 

Public Attributes

std::unique_ptr< UnsteadySolvercore_time_solver
 
SystemNorm component_norm
 
std::vector< float > component_scale
 
Real target_tolerance
 
Real upper_tolerance
 
Real max_deltat
 
Real min_deltat
 
Real max_growth
 
bool global_tolerance
 
std::unique_ptr< NumericVector< Number > > old_local_nonlinear_solution
 
bool quiet
 
unsigned int reduce_deltat_on_diffsolver_failure
 

Protected Types

typedef bool(DifferentiablePhysics::* ResFuncType) (bool, DiffContext &)
 
typedef void(DiffContext::* ReinitFuncType) (Real)
 
typedef std::map< std::string, std::pair< unsigned int, unsigned int > > Counts
 

Protected Member Functions

virtual Real calculate_norm (System &, NumericVector< Number > &)
 
void prepare_accel (DiffContext &context)
 
bool compute_second_order_eqns (bool compute_jacobian, DiffContext &c)
 
void increment_constructor_count (const std::string &name)
 
void increment_destructor_count (const std::string &name)
 

Protected Attributes

Real last_deltat
 
bool first_solve
 
bool first_adjoint_step
 
std::unique_ptr< DiffSolver_diff_solver
 
std::unique_ptr< LinearSolver< Number > > _linear_solver
 
sys_type_system
 
std::unique_ptr< SolutionHistorysolution_history
 

Static Protected Attributes

static Counts _counts
 
static Threads::atomic< unsigned int > _n_objects
 
static Threads::spin_mutex _mutex
 
static bool _enable_print_counter = true
 

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.

Author
Roy H. Stogner
Date
2007

Definition at line 50 of file twostep_time_solver.h.

Member Typedef Documentation

◆ Counts

typedef std::map<std::string, std::pair<unsigned int, unsigned int> > libMesh::ReferenceCounter::Counts
protectedinherited

Data structure to log the information. The log is identified by the class name.

Definition at line 117 of file reference_counter.h.

◆ Parent

The parent class

Definition at line 56 of file twostep_time_solver.h.

◆ ReinitFuncType

typedef void(DiffContext::* libMesh::TimeSolver::ReinitFuncType) (Real)
protectedinherited

Definition at line 273 of file time_solver.h.

◆ ResFuncType

typedef bool(DifferentiablePhysics::* libMesh::TimeSolver::ResFuncType) (bool, DiffContext &)
protectedinherited

Definitions of argument types for use in refactoring subclasses.

Definition at line 271 of file time_solver.h.

◆ sys_type

The type of system

Definition at line 65 of file time_solver.h.

Constructor & Destructor Documentation

◆ TwostepTimeSolver()

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.

31 
32 {
33  // We start with a reasonable time solver: implicit Euler
34  core_time_solver.reset(new EulerSolver(s));
35 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ ~TwostepTimeSolver()

libMesh::TwostepTimeSolver::~TwostepTimeSolver ( )

Destructor.

Definition at line 39 of file twostep_time_solver.C.

40 {
41 }

Member Function Documentation

◆ adjoint_advance_timestep()

void libMesh::UnsteadySolver::adjoint_advance_timestep ( )
overridevirtualinherited

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.

Reimplemented in libMesh::NewmarkSolver.

Definition at line 178 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.

179 {
180  // On the first call of this function, we dont save the adjoint solution or
181  // decrement the time, we just call the retrieve function below
182  if (!first_adjoint_step)
183  {
184  // Call the store function to store the last adjoint before decrementing the time
185  solution_history->store();
186  // Decrement the system time
188  }
189  else
190  {
191  first_adjoint_step = false;
192  }
193 
194  // Retrieve the primal solution vectors at this time using the
195  // solution_history object
196  solution_history->retrieve();
197 
198  // Dont forget to localize the old_nonlinear_solution !
199  _system.get_vector("_old_nonlinear_solution").localize
202 }
std::unique_ptr< NumericVector< Number > > old_local_nonlinear_solution
std::unique_ptr< SolutionHistory > solution_history
Definition: time_solver.h:265
sys_type & _system
Definition: time_solver.h:258
const NumericVector< Number > & get_vector(const std::string &vec_name) const
Definition: system.C:774
const DofMap & get_dof_map() const
Definition: system.h:2049
const std::vector< dof_id_type > & get_send_list() const
Definition: dof_map.h:450
virtual void localize(std::vector< T > &v_local) const =0

◆ advance_timestep()

void libMesh::AdaptiveTimeSolver::advance_timestep ( )
overridevirtualinherited

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 87 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.

88 {
89  NumericVector<Number> & old_nonlinear_soln =
90  _system.get_vector("_old_nonlinear_solution");
91  NumericVector<Number> & nonlinear_solution =
92  *(_system.solution);
93 
94  old_nonlinear_soln = nonlinear_solution;
95 
96  if (!first_solve)
98 }
sys_type & _system
Definition: time_solver.h:258
const NumericVector< Number > & get_vector(const std::string &vec_name) const
Definition: system.C:774
std::unique_ptr< NumericVector< Number > > solution
Definition: system.h:1523

◆ before_timestep()

virtual void libMesh::TimeSolver::before_timestep ( )
inlinevirtualinherited

This method is for subclasses or users to override to do arbitrary processing between timesteps

Definition at line 167 of file time_solver.h.

167 {}

◆ calculate_norm()

Real libMesh::AdaptiveTimeSolver::calculate_norm ( System s,
NumericVector< Number > &  v 
)
protectedvirtualinherited

A helper function to calculate error norms

Definition at line 155 of file adaptive_time_solver.C.

References libMesh::System::calculate_norm(), and libMesh::AdaptiveTimeSolver::component_norm.

Referenced by solve().

157 {
158  return s.calculate_norm(v, component_norm);
159 }

◆ compute_second_order_eqns()

bool libMesh::FirstOrderUnsteadySolver::compute_second_order_eqns ( bool  compute_jacobian,
DiffContext c 
)
protectedinherited

If there are second order variables, then we need to compute their residual equations and corresponding Jacobian. The residual equation will simply be $ \dot{u} - v = 0 $, where $ u $ is the second order variable add by the user and $ v $ is the variable added by the time-solver as the "velocity" variable.

Definition at line 32 of file first_order_unsteady_solver.C.

References libMesh::TimeSolver::_system, libMesh::DiffContext::get_dof_indices(), libMesh::DiffContext::get_elem_jacobian(), libMesh::DiffContext::get_elem_residual(), libMesh::DiffContext::get_elem_solution_derivative(), libMesh::DiffContext::get_elem_solution_rate_derivative(), libMesh::FEMContext::get_element_fe(), libMesh::FEMContext::get_element_qrule(), libMesh::DifferentiableSystem::get_second_order_dot_var(), libMesh::DiffContext::get_system(), libMesh::FEMContext::interior_rate(), libMesh::FEMContext::interior_value(), libMesh::DifferentiablePhysics::is_second_order_var(), libMesh::QBase::n_points(), libMesh::DiffContext::n_vars(), libMesh::Variable::type(), and libMesh::System::variable().

Referenced by libMesh::EulerSolver::_general_residual(), libMesh::Euler2Solver::_general_residual(), libMesh::EulerSolver::element_residual(), libMesh::Euler2Solver::element_residual(), libMesh::EulerSolver::nonlocal_residual(), and libMesh::Euler2Solver::nonlocal_residual().

33 {
34  FEMContext & context = cast_ref<FEMContext &>(c);
35 
36  unsigned int n_qpoints = context.get_element_qrule().n_points();
37 
38  for (unsigned int var = 0; var != context.n_vars(); ++var)
39  {
40  if (!this->_system.is_second_order_var(var))
41  continue;
42 
43  unsigned int dot_var = this->_system.get_second_order_dot_var(var);
44 
45  // We're assuming that the FE space for var and dot_var are the same
46  libmesh_assert( context.get_system().variable(var).type() ==
47  context.get_system().variable(dot_var).type() );
48 
49  FEBase * elem_fe = nullptr;
50  context.get_element_fe( var, elem_fe );
51 
52  const std::vector<Real> & JxW = elem_fe->get_JxW();
53 
54  const std::vector<std::vector<Real>> & phi = elem_fe->get_phi();
55 
56  const unsigned int n_dofs = cast_int<unsigned int>
57  (context.get_dof_indices(dot_var).size());
58 
59  DenseSubVector<Number> & Fu = context.get_elem_residual(var);
60  DenseSubMatrix<Number> & Kuu = context.get_elem_jacobian( var, var );
61  DenseSubMatrix<Number> & Kuv = context.get_elem_jacobian( var, dot_var );
62 
63  for (unsigned int qp = 0; qp != n_qpoints; ++qp)
64  {
65  Number udot, v;
66  context.interior_rate(var, qp, udot);
67  context.interior_value(dot_var, qp, v);
68 
69  for (unsigned int i = 0; i < n_dofs; i++)
70  {
71  Fu(i) += JxW[qp]*(udot-v)*phi[i][qp];
72 
73  if (compute_jacobian)
74  {
75  Number rate_factor = JxW[qp]*context.get_elem_solution_rate_derivative()*phi[i][qp];
76  Number soln_factor = JxW[qp]*context.get_elem_solution_derivative()*phi[i][qp];
77 
78  Kuu(i,i) += rate_factor*phi[i][qp];
79  Kuv(i,i) -= soln_factor*phi[i][qp];
80 
81  for (unsigned int j = i+1; j < n_dofs; j++)
82  {
83  Kuu(i,j) += rate_factor*phi[j][qp];
84  Kuu(j,i) += rate_factor*phi[j][qp];
85 
86  Kuv(i,j) -= soln_factor*phi[j][qp];
87  Kuv(j,i) -= soln_factor*phi[j][qp];
88  }
89  }
90  }
91  }
92  }
93 
94  return compute_jacobian;
95 }
bool is_second_order_var(unsigned int var) const
Definition: diff_physics.h:533
sys_type & _system
Definition: time_solver.h:258
unsigned int get_second_order_dot_var(unsigned int var) const
Definition: diff_system.C:306
FEGenericBase< Real > FEBase

◆ diff_solver()

std::unique_ptr< DiffSolver > & libMesh::AdaptiveTimeSolver::diff_solver ( )
overridevirtualinherited

An implicit linear or nonlinear solver to use at each timestep.

Reimplemented from libMesh::TimeSolver.

Definition at line 141 of file adaptive_time_solver.C.

References libMesh::AdaptiveTimeSolver::core_time_solver.

142 {
143  return core_time_solver->diff_solver();
144 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ disable_print_counter_info()

void libMesh::ReferenceCounter::disable_print_counter_info ( )
staticinherited

Definition at line 106 of file reference_counter.C.

References libMesh::ReferenceCounter::_enable_print_counter.

Referenced by libMesh::LibMeshInit::LibMeshInit().

107 {
108  _enable_print_counter = false;
109  return;
110 }

◆ du()

Real libMesh::UnsteadySolver::du ( const SystemNorm norm) const
overridevirtualinherited

Computes the size of ||u^{n+1} - u^{n}|| in some norm.

Note
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 227 of file unsteady_solver.C.

References libMesh::TimeSolver::_system, libMesh::System::calculate_norm(), libMesh::System::get_vector(), and libMesh::System::solution.

228 {
229 
230  std::unique_ptr<NumericVector<Number>> solution_copy =
231  _system.solution->clone();
232 
233  solution_copy->add(-1., _system.get_vector("_old_nonlinear_solution"));
234 
235  solution_copy->close();
236 
237  return _system.calculate_norm(*solution_copy, norm);
238 }
sys_type & _system
Definition: time_solver.h:258
const NumericVector< Number > & get_vector(const std::string &vec_name) const
Definition: system.C:774
std::unique_ptr< NumericVector< Number > > solution
Definition: system.h:1523
Real calculate_norm(const NumericVector< Number > &v, unsigned int var, FEMNormType norm_type, std::set< unsigned int > *skip_dimensions=nullptr) const
Definition: system.C:1378

◆ element_residual()

bool libMesh::AdaptiveTimeSolver::element_residual ( bool  get_jacobian,
DiffContext context 
)
overridevirtualinherited

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.

113 {
114  libmesh_assert(core_time_solver.get());
115 
116  return core_time_solver->element_residual(request_jacobian, context);
117 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ enable_print_counter_info()

void libMesh::ReferenceCounter::enable_print_counter_info ( )
staticinherited

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.

101 {
102  _enable_print_counter = true;
103  return;
104 }

◆ error_order()

Real libMesh::AdaptiveTimeSolver::error_order ( ) const
overridevirtualinherited

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.

103 {
104  libmesh_assert(core_time_solver.get());
105 
106  return core_time_solver->error_order();
107 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ get_info()

std::string libMesh::ReferenceCounter::get_info ( )
staticinherited

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().

48 {
49 #if defined(LIBMESH_ENABLE_REFERENCE_COUNTING) && defined(DEBUG)
50 
51  std::ostringstream oss;
52 
53  oss << '\n'
54  << " ---------------------------------------------------------------------------- \n"
55  << "| Reference count information |\n"
56  << " ---------------------------------------------------------------------------- \n";
57 
58  for (const auto & pr : _counts)
59  {
60  const std::string name(pr.first);
61  const unsigned int creations = pr.second.first;
62  const unsigned int destructions = pr.second.second;
63 
64  oss << "| " << name << " reference count information:\n"
65  << "| Creations: " << creations << '\n'
66  << "| Destructions: " << destructions << '\n';
67  }
68 
69  oss << " ---------------------------------------------------------------------------- \n";
70 
71  return oss.str();
72 
73 #else
74 
75  return "";
76 
77 #endif
78 }
std::string name(const ElemQuality q)
Definition: elem_quality.C:42

◆ increment_constructor_count()

void libMesh::ReferenceCounter::increment_constructor_count ( const std::string &  name)
inlineprotectedinherited

Increments the construction counter. Should be called in the constructor of any derived class that will be reference counted.

Definition at line 181 of file reference_counter.h.

References libMesh::ReferenceCounter::_counts, libMesh::Quality::name(), and libMesh::Threads::spin_mtx.

Referenced by libMesh::ReferenceCountedObject< RBParametrized >::ReferenceCountedObject().

182 {
183  Threads::spin_mutex::scoped_lock lock(Threads::spin_mtx);
184  std::pair<unsigned int, unsigned int> & p = _counts[name];
185 
186  p.first++;
187 }
std::string name(const ElemQuality q)
Definition: elem_quality.C:42
spin_mutex spin_mtx
Definition: threads.C:29

◆ increment_destructor_count()

void libMesh::ReferenceCounter::increment_destructor_count ( const std::string &  name)
inlineprotectedinherited

Increments the destruction counter. Should be called in the destructor of any derived class that will be reference counted.

Definition at line 194 of file reference_counter.h.

References libMesh::ReferenceCounter::_counts, libMesh::Quality::name(), and libMesh::Threads::spin_mtx.

Referenced by libMesh::ReferenceCountedObject< RBParametrized >::~ReferenceCountedObject().

195 {
196  Threads::spin_mutex::scoped_lock lock(Threads::spin_mtx);
197  std::pair<unsigned int, unsigned int> & p = _counts[name];
198 
199  p.second++;
200 }
std::string name(const ElemQuality q)
Definition: elem_quality.C:42
spin_mutex spin_mtx
Definition: threads.C:29

◆ init()

void libMesh::AdaptiveTimeSolver::init ( )
overridevirtualinherited

The initialization function. This method is used to initialize internal data structures before a simulation begins.

Reimplemented from libMesh::UnsteadySolver.

Definition at line 58 of file adaptive_time_solver.C.

References libMesh::AdaptiveTimeSolver::core_time_solver, and libMesh::UnsteadySolver::old_local_nonlinear_solution.

59 {
60  libmesh_assert(core_time_solver.get());
61 
62  // We override this because our core_time_solver is the one that
63  // needs to handle new vectors, diff_solver->init(), etc
64  core_time_solver->init();
65 
66  // As an UnsteadySolver, we have an old_local_nonlinear_solution, but it
67  // isn't pointing to the right place - fix it
68  //
69  // This leaves us with two std::unique_ptrs holding the same pointer - dangerous
70  // for future use. Replace with shared_ptr?
72  std::unique_ptr<NumericVector<Number>>(core_time_solver->old_local_nonlinear_solution.get());
73 }
std::unique_ptr< NumericVector< Number > > old_local_nonlinear_solution
std::unique_ptr< UnsteadySolver > core_time_solver

◆ init_data()

void libMesh::UnsteadySolver::init_data ( )
overridevirtualinherited

The data initialization function. This method is used to initialize internal data structures after the underlying System has been initialized

Reimplemented from libMesh::TimeSolver.

Reimplemented in libMesh::SecondOrderUnsteadySolver.

Definition at line 55 of file unsteady_solver.C.

References libMesh::TimeSolver::_system, libMesh::System::get_dof_map(), libMesh::DofMap::get_send_list(), libMesh::GHOSTED, libMesh::TimeSolver::init_data(), libMesh::System::n_dofs(), libMesh::System::n_local_dofs(), libMesh::UnsteadySolver::old_local_nonlinear_solution, and libMesh::SERIAL.

Referenced by libMesh::SecondOrderUnsteadySolver::init_data().

56 {
58 
59 #ifdef LIBMESH_ENABLE_GHOSTED
62  GHOSTED);
63 #else
65 #endif
66 }
std::unique_ptr< NumericVector< Number > > old_local_nonlinear_solution
virtual void init_data()
Definition: time_solver.C:77
dof_id_type n_local_dofs() const
Definition: system.C:187
dof_id_type n_dofs() const
Definition: system.C:150
sys_type & _system
Definition: time_solver.h:258
const DofMap & get_dof_map() const
Definition: system.h:2049
const std::vector< dof_id_type > & get_send_list() const
Definition: dof_map.h:450

◆ is_adjoint()

bool libMesh::TimeSolver::is_adjoint ( ) const
inlineinherited

Accessor for querying whether we need to do a primal or adjoint solve

Definition at line 233 of file time_solver.h.

References libMesh::TimeSolver::_is_adjoint.

Referenced by libMesh::FEMSystem::build_context().

234  { return _is_adjoint; }

◆ is_steady()

virtual bool libMesh::UnsteadySolver::is_steady ( ) const
inlineoverridevirtualinherited

This is not a steady-state solver.

Implements libMesh::TimeSolver.

Definition at line 154 of file unsteady_solver.h.

154 { return false; }

◆ linear_solver()

std::unique_ptr< LinearSolver< Number > > & libMesh::AdaptiveTimeSolver::linear_solver ( )
overridevirtualinherited

An implicit linear solver to use for adjoint and sensitivity problems.

Reimplemented from libMesh::TimeSolver.

Definition at line 148 of file adaptive_time_solver.C.

References libMesh::AdaptiveTimeSolver::core_time_solver.

149 {
150  return core_time_solver->linear_solver();
151 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ n_objects()

static unsigned int libMesh::ReferenceCounter::n_objects ( )
inlinestaticinherited

Prints the number of outstanding (created, but not yet destroyed) objects.

Definition at line 83 of file reference_counter.h.

References libMesh::ReferenceCounter::_n_objects.

84  { return _n_objects; }
static Threads::atomic< unsigned int > _n_objects

◆ nonlocal_residual()

bool libMesh::AdaptiveTimeSolver::nonlocal_residual ( bool  get_jacobian,
DiffContext context 
)
overridevirtualinherited

This method is passed on to the core_time_solver

Implements libMesh::TimeSolver.

Definition at line 131 of file adaptive_time_solver.C.

References libMesh::AdaptiveTimeSolver::core_time_solver.

133 {
134  libmesh_assert(core_time_solver.get());
135 
136  return core_time_solver->nonlocal_residual(request_jacobian, context);
137 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ old_nonlinear_solution()

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 216 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::_general_residual(), libMesh::Euler2Solver::_general_residual(), and libMesh::NewmarkSolver::_general_residual().

218 {
219  libmesh_assert_less (global_dof_number, _system.get_dof_map().n_dofs());
220  libmesh_assert_less (global_dof_number, old_local_nonlinear_solution->size());
221 
222  return (*old_local_nonlinear_solution)(global_dof_number);
223 }
std::unique_ptr< NumericVector< Number > > old_local_nonlinear_solution
sys_type & _system
Definition: time_solver.h:258
dof_id_type n_dofs() const
Definition: dof_map.h:574
const DofMap & get_dof_map() const
Definition: system.h:2049

◆ prepare_accel()

void libMesh::FirstOrderUnsteadySolver::prepare_accel ( DiffContext context)
protectedinherited

If there are second order variables in the system, then we also prepare the accel for those variables so the user can treat them as such.

Definition at line 25 of file first_order_unsteady_solver.C.

References libMesh::DiffContext::elem_solution_accel_derivative, libMesh::DiffContext::get_elem_solution_accel(), libMesh::DiffContext::get_elem_solution_rate(), and libMesh::DiffContext::get_elem_solution_rate_derivative().

Referenced by libMesh::EulerSolver::_general_residual(), and libMesh::Euler2Solver::_general_residual().

26 {
27  context.get_elem_solution_accel() = context.get_elem_solution_rate();
28 
29  context.elem_solution_accel_derivative = context.get_elem_solution_rate_derivative();
30 }

◆ print_info()

void libMesh::ReferenceCounter::print_info ( std::ostream &  out = libMesh::out)
staticinherited

Prints the reference information, by default to libMesh::out.

Definition at line 87 of file reference_counter.C.

References libMesh::ReferenceCounter::_enable_print_counter, and libMesh::ReferenceCounter::get_info().

88 {
90  out_stream << ReferenceCounter::get_info();
91 }
static std::string get_info()

◆ reinit()

void libMesh::AdaptiveTimeSolver::reinit ( )
overridevirtualinherited

The reinitialization function. This method is used to resize internal data vectors after a mesh change.

Reimplemented from libMesh::UnsteadySolver.

Definition at line 77 of file adaptive_time_solver.C.

References libMesh::AdaptiveTimeSolver::core_time_solver.

78 {
79  libmesh_assert(core_time_solver.get());
80 
81  // We override this because our core_time_solver is the one that
82  // needs to handle new vectors, diff_solver->reinit(), etc
83  core_time_solver->reinit();
84 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ retrieve_timestep()

void libMesh::UnsteadySolver::retrieve_timestep ( )
overridevirtualinherited

This method retrieves all the stored solutions at the current system.time

Reimplemented from libMesh::TimeSolver.

Reimplemented in libMesh::SecondOrderUnsteadySolver.

Definition at line 204 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.

205 {
206  // Retrieve all the stored vectors at the current time
207  solution_history->retrieve();
208 
209  // Dont forget to localize the old_nonlinear_solution !
210  _system.get_vector("_old_nonlinear_solution").localize
213 }
std::unique_ptr< NumericVector< Number > > old_local_nonlinear_solution
std::unique_ptr< SolutionHistory > solution_history
Definition: time_solver.h:265
sys_type & _system
Definition: time_solver.h:258
const NumericVector< Number > & get_vector(const std::string &vec_name) const
Definition: system.C:774
const DofMap & get_dof_map() const
Definition: system.h:2049
const std::vector< dof_id_type > & get_send_list() const
Definition: dof_map.h:450
virtual void localize(std::vector< T > &v_local) const =0

◆ set_is_adjoint()

void libMesh::TimeSolver::set_is_adjoint ( bool  _is_adjoint_value)
inlineinherited

Accessor for setting whether we need to do a primal or adjoint solve

Definition at line 240 of file time_solver.h.

References libMesh::TimeSolver::_is_adjoint.

Referenced by libMesh::DifferentiableSystem::adjoint_solve(), libMesh::FEMSystem::postprocess(), and libMesh::DifferentiableSystem::solve().

241  { _is_adjoint = _is_adjoint_value; }

◆ set_solution_history()

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 97 of file time_solver.C.

References libMesh::SolutionHistory::clone(), and libMesh::TimeSolver::solution_history.

98 {
99  solution_history = _solution_history.clone();
100 }
std::unique_ptr< SolutionHistory > solution_history
Definition: time_solver.h:265

◆ side_residual()

bool libMesh::AdaptiveTimeSolver::side_residual ( bool  get_jacobian,
DiffContext context 
)
overridevirtualinherited

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.

123 {
124  libmesh_assert(core_time_solver.get());
125 
126  return core_time_solver->side_residual(request_jacobian, context);
127 }
std::unique_ptr< UnsteadySolver > core_time_solver

◆ solve()

void libMesh::TwostepTimeSolver::solve ( )
overridevirtual

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::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.

46 {
47  libmesh_assert(core_time_solver.get());
48 
49  // The core_time_solver will handle any first_solve actions
50  first_solve = false;
51 
52  // We may have to repeat timesteps entirely if our error is bad
53  // enough
54  bool max_tolerance_met = false;
55 
56  // Calculating error values each time
57  Real single_norm(0.), double_norm(0.), error_norm(0.),
58  relative_error(0.);
59 
60  while (!max_tolerance_met)
61  {
62  // If we've been asked to reduce deltat if necessary, make sure
63  // the core timesolver does so
64  core_time_solver->reduce_deltat_on_diffsolver_failure =
66 
67  if (!quiet)
68  {
69  libMesh::out << "\n === Computing adaptive timestep === "
70  << std::endl;
71  }
72 
73  // Use the double-length timestep first (so the
74  // old_nonlinear_solution won't have to change)
75  core_time_solver->solve();
76 
77  // Save a copy of the double-length nonlinear solution
78  // and the old nonlinear solution
79  std::unique_ptr<NumericVector<Number>> double_solution =
80  _system.solution->clone();
81  std::unique_ptr<NumericVector<Number>> old_solution =
82  _system.get_vector("_old_nonlinear_solution").clone();
83 
84  double_norm = calculate_norm(_system, *double_solution);
85  if (!quiet)
86  {
87  libMesh::out << "Double norm = " << double_norm << std::endl;
88  }
89 
90  // Then reset the initial guess for our single-length calcs
91  *(_system.solution) = _system.get_vector("_old_nonlinear_solution");
92 
93  // Call two single-length timesteps
94  // Be sure that the core_time_solver does not change the
95  // timestep here. (This is unlikely because it just succeeded
96  // with a timestep twice as large!)
97  // FIXME: even if diffsolver failure is unlikely, we ought to
98  // do *something* if it happens
99  core_time_solver->reduce_deltat_on_diffsolver_failure = 0;
100 
101  Real old_time = _system.time;
102  Real old_deltat = _system.deltat;
103  _system.deltat *= 0.5;
104  core_time_solver->solve();
105  core_time_solver->advance_timestep();
106  core_time_solver->solve();
107 
108  single_norm = calculate_norm(_system, *_system.solution);
109  if (!quiet)
110  {
111  libMesh::out << "Single norm = " << single_norm << std::endl;
112  }
113 
114  // Reset the core_time_solver's reduce_deltat... value.
115  core_time_solver->reduce_deltat_on_diffsolver_failure =
117 
118  // But then back off just in case our advance_timestep() isn't
119  // called.
120  // FIXME: this probably doesn't work with multistep methods
121  _system.get_vector("_old_nonlinear_solution") = *old_solution;
122  _system.time = old_time;
123  _system.deltat = old_deltat;
124 
125  // Find the relative error
126  *double_solution -= *(_system.solution);
127  error_norm = calculate_norm(_system, *double_solution);
128  relative_error = error_norm / _system.deltat /
129  std::max(double_norm, single_norm);
130 
131  // If the relative error makes no sense, we're done
132  if (!double_norm && !single_norm)
133  return;
134 
135  if (!quiet)
136  {
137  libMesh::out << "Error norm = " << error_norm << std::endl;
138  libMesh::out << "Local relative error = "
139  << (error_norm /
140  std::max(double_norm, single_norm))
141  << std::endl;
142  libMesh::out << "Global relative error = "
143  << (error_norm / _system.deltat /
144  std::max(double_norm, single_norm))
145  << std::endl;
146  libMesh::out << "old delta t = " << _system.deltat << std::endl;
147  }
148 
149  // If our upper tolerance is negative, that means we want to set
150  // it based on the first successful time step
151  if (this->upper_tolerance < 0)
152  this->upper_tolerance = -this->upper_tolerance * relative_error;
153 
154  // If we haven't met our upper error tolerance, we'll have to
155  // repeat this timestep entirely
156  if (this->upper_tolerance && relative_error > this->upper_tolerance)
157  {
158  // Reset the initial guess for our next try
159  *(_system.solution) =
160  _system.get_vector("_old_nonlinear_solution");
161 
162  // Chop delta t in half
163  _system.deltat /= 2.;
164 
165  if (!quiet)
166  {
167  libMesh::out << "Failed to meet upper error tolerance"
168  << std::endl;
169  libMesh::out << "Retrying with delta t = "
170  << _system.deltat << std::endl;
171  }
172  }
173  else
174  max_tolerance_met = true;
175  }
176 
177 
178  // Otherwise, compare the relative error to the tolerance
179  // and adjust deltat
181 
182  // If our target tolerance is negative, that means we want to set
183  // it based on the first successful time step
184  if (this->target_tolerance < 0)
185  this->target_tolerance = -this->target_tolerance * relative_error;
186 
187  const Real global_shrink_or_growth_factor =
188  std::pow(this->target_tolerance / relative_error,
189  static_cast<Real>(1. / core_time_solver->error_order()));
190 
191  const Real local_shrink_or_growth_factor =
192  std::pow(this->target_tolerance /
193  (error_norm/std::max(double_norm, single_norm)),
194  static_cast<Real>(1. / (core_time_solver->error_order()+1.)));
195 
196  if (!quiet)
197  {
198  libMesh::out << "The global growth/shrink factor is: "
199  << global_shrink_or_growth_factor << std::endl;
200  libMesh::out << "The local growth/shrink factor is: "
201  << local_shrink_or_growth_factor << std::endl;
202  }
203 
204  // The local s.o.g. factor is based on the expected **local**
205  // truncation error for the timestepping method, the global
206  // s.o.g. factor is based on the method's **global** truncation
207  // error. You can shrink/grow the timestep to attempt to satisfy
208  // either a global or local time-discretization error tolerance.
209 
210  Real shrink_or_growth_factor =
211  this->global_tolerance ? global_shrink_or_growth_factor :
212  local_shrink_or_growth_factor;
213 
214  if (this->max_growth && this->max_growth < shrink_or_growth_factor)
215  {
216  if (!quiet && this->global_tolerance)
217  {
218  libMesh::out << "delta t is constrained by max_growth" << std::endl;
219  }
220  shrink_or_growth_factor = this->max_growth;
221  }
222 
223  _system.deltat *= shrink_or_growth_factor;
224 
225  // Restrict deltat to max-allowable value if necessary
226  if ((this->max_deltat != 0.0) && (_system.deltat > this->max_deltat))
227  {
228  if (!quiet)
229  {
230  libMesh::out << "delta t is constrained by maximum-allowable delta t."
231  << std::endl;
232  }
233  _system.deltat = this->max_deltat;
234  }
235 
236  // Restrict deltat to min-allowable value if necessary
237  if ((this->min_deltat != 0.0) && (_system.deltat < this->min_deltat))
238  {
239  if (!quiet)
240  {
241  libMesh::out << "delta t is constrained by minimum-allowable delta t."
242  << std::endl;
243  }
244  _system.deltat = this->min_deltat;
245  }
246 
247  if (!quiet)
248  {
249  libMesh::out << "new delta t = " << _system.deltat << std::endl;
250  }
251 }
virtual Real calculate_norm(System &, NumericVector< Number > &)
virtual std::unique_ptr< NumericVector< T > > clone() const =0
long double max(long double a, double b)
sys_type & _system
Definition: time_solver.h:258
const NumericVector< Number > & get_vector(const std::string &vec_name) const
Definition: system.C:774
std::unique_ptr< NumericVector< Number > > solution
Definition: system.h:1523
unsigned int reduce_deltat_on_diffsolver_failure
Definition: time_solver.h:221
double pow(double a, int b)
DIE A HORRIBLE DEATH HERE typedef LIBMESH_DEFAULT_SCALAR_TYPE Real
OStreamProxy out(std::cout)
std::unique_ptr< UnsteadySolver > core_time_solver

◆ system() [1/2]

const sys_type& libMesh::TimeSolver::system ( ) const
inlineinherited
Returns
A constant reference to the system we are solving.

Definition at line 172 of file time_solver.h.

References libMesh::TimeSolver::_system.

Referenced by libMesh::TimeSolver::reinit(), and libMesh::TimeSolver::solve().

172 { return _system; }
sys_type & _system
Definition: time_solver.h:258

◆ system() [2/2]

sys_type& libMesh::TimeSolver::system ( )
inlineinherited
Returns
A writable reference to the system we are solving.

Definition at line 177 of file time_solver.h.

References libMesh::TimeSolver::_system.

177 { return _system; }
sys_type & _system
Definition: time_solver.h:258

◆ time_order()

virtual unsigned int libMesh::FirstOrderUnsteadySolver::time_order ( ) const
inlineoverridevirtualinherited
Returns
The maximum order of time derivatives for which the UnsteadySolver subclass is capable of handling.

For example, EulerSolver will have time_order() = 1 and NewmarkSolver will have time_order() = 2.

Implements libMesh::UnsteadySolver.

Definition at line 90 of file first_order_unsteady_solver.h.

91  { return 1; }

Member Data Documentation

◆ _counts

ReferenceCounter::Counts libMesh::ReferenceCounter::_counts
staticprotectedinherited

◆ _diff_solver

std::unique_ptr<DiffSolver> libMesh::TimeSolver::_diff_solver
protectedinherited

An implicit linear or nonlinear solver to use at each timestep.

Definition at line 248 of file time_solver.h.

Referenced by libMesh::NewmarkSolver::compute_initial_accel(), libMesh::TimeSolver::diff_solver(), and libMesh::UnsteadySolver::solve().

◆ _enable_print_counter

bool libMesh::ReferenceCounter::_enable_print_counter = true
staticprotectedinherited

Flag to control whether reference count information is printed when print_info is called.

Definition at line 141 of file reference_counter.h.

Referenced by libMesh::ReferenceCounter::disable_print_counter_info(), libMesh::ReferenceCounter::enable_print_counter_info(), and libMesh::ReferenceCounter::print_info().

◆ _linear_solver

std::unique_ptr<LinearSolver<Number> > libMesh::TimeSolver::_linear_solver
protectedinherited

An implicit linear solver to use for adjoint problems.

Definition at line 253 of file time_solver.h.

Referenced by libMesh::TimeSolver::linear_solver().

◆ _mutex

Threads::spin_mutex libMesh::ReferenceCounter::_mutex
staticprotectedinherited

Mutual exclusion object to enable thread-safe reference counting.

Definition at line 135 of file reference_counter.h.

◆ _n_objects

Threads::atomic< unsigned int > libMesh::ReferenceCounter::_n_objects
staticprotectedinherited

The number of objects. Print the reference count information when the number returns to 0.

Definition at line 130 of file reference_counter.h.

Referenced by libMesh::ReferenceCounter::n_objects(), libMesh::ReferenceCounter::ReferenceCounter(), and libMesh::ReferenceCounter::~ReferenceCounter().

◆ _system

sys_type& libMesh::TimeSolver::_system
protectedinherited

A reference to the system we are solving.

Definition at line 258 of file time_solver.h.

Referenced by libMesh::EulerSolver::_general_residual(), libMesh::Euler2Solver::_general_residual(), libMesh::SteadySolver::_general_residual(), libMesh::NewmarkSolver::_general_residual(), libMesh::UnsteadySolver::adjoint_advance_timestep(), libMesh::NewmarkSolver::advance_timestep(), libMesh::AdaptiveTimeSolver::advance_timestep(), libMesh::UnsteadySolver::advance_timestep(), libMesh::NewmarkSolver::compute_initial_accel(), libMesh::FirstOrderUnsteadySolver::compute_second_order_eqns(), libMesh::UnsteadySolver::du(), libMesh::EulerSolver::element_residual(), libMesh::Euler2Solver::element_residual(), libMesh::EigenTimeSolver::element_residual(), libMesh::SecondOrderUnsteadySolver::init(), libMesh::UnsteadySolver::init(), libMesh::TimeSolver::init(), libMesh::EigenTimeSolver::init(), libMesh::SecondOrderUnsteadySolver::init_data(), libMesh::UnsteadySolver::init_data(), libMesh::TimeSolver::init_data(), libMesh::EulerSolver::nonlocal_residual(), libMesh::Euler2Solver::nonlocal_residual(), libMesh::EigenTimeSolver::nonlocal_residual(), libMesh::UnsteadySolver::old_nonlinear_solution(), libMesh::SecondOrderUnsteadySolver::old_solution_accel(), libMesh::SecondOrderUnsteadySolver::old_solution_rate(), libMesh::NewmarkSolver::project_initial_accel(), libMesh::SecondOrderUnsteadySolver::project_initial_rate(), libMesh::SecondOrderUnsteadySolver::reinit(), libMesh::UnsteadySolver::reinit(), libMesh::TimeSolver::reinit(), libMesh::UnsteadySolver::retrieve_timestep(), libMesh::EigenTimeSolver::side_residual(), solve(), libMesh::UnsteadySolver::solve(), libMesh::EigenTimeSolver::solve(), and libMesh::TimeSolver::system().

◆ component_norm

SystemNorm libMesh::AdaptiveTimeSolver::component_norm
inherited

Error calculations are done in this norm, DISCRETE_L2 by default.

Definition at line 119 of file adaptive_time_solver.h.

Referenced by libMesh::AdaptiveTimeSolver::calculate_norm().

◆ component_scale

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 127 of file adaptive_time_solver.h.

◆ core_time_solver

◆ first_adjoint_step

bool libMesh::UnsteadySolver::first_adjoint_step
protectedinherited

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 168 of file unsteady_solver.h.

Referenced by libMesh::UnsteadySolver::adjoint_advance_timestep().

◆ first_solve

bool libMesh::UnsteadySolver::first_solve
protectedinherited

A bool that will be true the first time solve() is called, and false thereafter

Definition at line 162 of file unsteady_solver.h.

Referenced by libMesh::NewmarkSolver::advance_timestep(), libMesh::AdaptiveTimeSolver::advance_timestep(), libMesh::UnsteadySolver::advance_timestep(), solve(), and libMesh::UnsteadySolver::solve().

◆ global_tolerance

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
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 198 of file adaptive_time_solver.h.

Referenced by solve().

◆ last_deltat

Real libMesh::AdaptiveTimeSolver::last_deltat
protectedinherited

We need to store the value of the last deltat used, so that advance_timestep() will increment the system time correctly.

Definition at line 207 of file adaptive_time_solver.h.

Referenced by libMesh::AdaptiveTimeSolver::advance_timestep(), and solve().

◆ max_deltat

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 167 of file adaptive_time_solver.h.

Referenced by solve().

◆ max_growth

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 181 of file adaptive_time_solver.h.

Referenced by solve().

◆ min_deltat

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 173 of file adaptive_time_solver.h.

Referenced by solve().

◆ old_local_nonlinear_solution

◆ quiet

bool libMesh::TimeSolver::quiet
inherited

Print extra debugging information if quiet == false.

Definition at line 192 of file time_solver.h.

Referenced by solve(), libMesh::UnsteadySolver::solve(), and libMesh::EigenTimeSolver::solve().

◆ reduce_deltat_on_diffsolver_failure

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
This has no effect for SteadySolvers.
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 221 of file time_solver.h.

Referenced by solve(), and libMesh::UnsteadySolver::solve().

◆ solution_history

std::unique_ptr<SolutionHistory> libMesh::TimeSolver::solution_history
protectedinherited

A std::unique_ptr 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 265 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().

◆ target_tolerance

Real libMesh::AdaptiveTimeSolver::target_tolerance
inherited

This tolerance is the target relative error between an exact time integration and a single time step output, scaled by deltat. integrator, scaled by deltat. If the estimated error exceeds or undershoots the target error tolerance, 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.

If a negative target_tolerance is specified, then its absolute value is used to scale the estimated error from the first simulation time step, and this becomes the target tolerance of all future time steps.

Definition at line 144 of file adaptive_time_solver.h.

Referenced by solve().

◆ upper_tolerance

Real libMesh::AdaptiveTimeSolver::upper_tolerance
inherited

This tolerance is the maximum relative error between an exact time integration and a single time step output, scaled by deltat. If this error tolerance is exceeded by the estimated error of the current time step, that time step will be repeated with a smaller deltat.

If you use the default upper_tolerance=0.0, then the current time step will not be repeated regardless of estimated error.

If a negative upper_tolerance is specified, then its absolute value is used to scale the estimated error from the first simulation time step, and this becomes the upper tolerance of all future time steps.

Definition at line 161 of file adaptive_time_solver.h.

Referenced by solve().


The documentation for this class was generated from the following files: