deal.II version GIT relicensing-1972-g22a7b89abe 2024-10-11 21:20:00+00:00
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#include <deal.II/lac/solver_control.h>
Public Types | |
enum | State { iterate = 0 , success , failure } |
Public Member Functions | |
ReductionControl (const unsigned int maxiter=100, const double tolerance=1.e-10, const double reduce=1.e-2, const bool log_history=false, const bool log_result=true) | |
ReductionControl (const SolverControl &c) | |
ReductionControl & | operator= (const SolverControl &c) |
virtual | ~ReductionControl () override=default |
void | parse_parameters (ParameterHandler ¶m) |
virtual State | check (const unsigned int step, const double check_value) override |
double | reduction () const |
double | set_reduction (const double) |
State | last_check () const |
double | initial_value () const |
double | last_value () const |
unsigned int | last_step () const |
unsigned int | max_steps () const |
unsigned int | set_max_steps (const unsigned int) |
void | set_failure_criterion (const double rel_failure_residual) |
void | clear_failure_criterion () |
double | tolerance () const |
double | set_tolerance (const double) |
void | enable_history_data () |
const std::vector< double > & | get_history_data () const |
double | average_reduction () const |
double | final_reduction () const |
double | step_reduction (unsigned int step) const |
void | log_history (const bool) |
bool | log_history () const |
unsigned int | log_frequency (unsigned int) |
void | log_result (const bool) |
bool | log_result () const |
template<class Archive > | |
void | serialize (Archive &ar, const unsigned int version) |
Subscriptor functionality | |
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the ObserverPointer class. | |
void | subscribe (std::atomic< bool > *const validity, const std::string &identifier="") const |
void | unsubscribe (std::atomic< bool > *const validity, const std::string &identifier="") const |
unsigned int | n_subscriptions () const |
template<typename StreamType > | |
void | list_subscribers (StreamType &stream) const |
void | list_subscribers () const |
Static Public Member Functions | |
static void | declare_parameters (ParameterHandler ¶m) |
static ::ExceptionBase & | ExcHistoryDataRequired () |
static ::ExceptionBase & | ExcInUse (int arg1, std::string arg2, std::string arg3) |
static ::ExceptionBase & | ExcNoSubscriber (std::string arg1, std::string arg2) |
Protected Attributes | |
double | reduce |
double | reduced_tol |
unsigned int | maxsteps |
double | tol |
State | lcheck |
double | initial_val |
double | lvalue |
unsigned int | lstep |
bool | check_failure |
double | relative_failure_residual |
double | failure_residual |
bool | m_log_history |
unsigned int | m_log_frequency |
bool | m_log_result |
bool | history_data_enabled |
std::vector< double > | history_data |
Private Types | |
using | map_value_type = decltype(counter_map)::value_type |
using | map_iterator = decltype(counter_map)::iterator |
Private Member Functions | |
void | check_no_subscribers () const noexcept |
Private Attributes | |
std::atomic< unsigned int > | counter |
std::map< std::string, unsigned int > | counter_map |
std::vector< std::atomic< bool > * > | validity_pointers |
const std::type_info * | object_info |
Static Private Attributes | |
static std::mutex | mutex |
Specialization of SolverControl
which returns success
if either the specified tolerance is achieved or if the initial residual (or whatever criterion was chosen by the solver class) is reduced by a given factor. This is useful in cases where you don't want to solve exactly, but rather want to gain two digits or if the maximal number of iterations is achieved. For example: The maximal number of iterations is 20, the reduction factor is 1% and the tolerance is 0.1%. The initial residual is 2.5. The process will break if 20 iteration are completed or the new residual is less then 2.5*1% or if it is less then 0.1%.
Definition at line 423 of file solver_control.h.
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privateinherited |
The data type used in counter_map.
Definition at line 230 of file subscriptor.h.
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privateinherited |
The iterator type used in counter_map.
Definition at line 235 of file subscriptor.h.
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inherited |
Enum denoting the different states a solver can be in. See the general documentation of this class for more information.
Enumerator | |
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iterate | Continue iteration. |
success | Stop iteration, goal reached. |
failure | Stop iteration, goal not reached. |
Definition at line 73 of file solver_control.h.
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explicit |
Constructor. Provide the reduction factor in addition to arguments that have the same meaning as those of the constructor of the SolverControl constructor.
Definition at line 229 of file solver_control.cc.
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explicit |
Initialize with a SolverControl object. The result will emulate SolverControl by setting reduce
to zero.
Definition at line 240 of file solver_control.cc.
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overridevirtualdefault |
Virtual destructor is needed as there are virtual functions in this class.
ReductionControl & ReductionControl::operator= | ( | const SolverControl & | c | ) |
Assign a SolverControl object to ReductionControl. The result of the assignment will emulate SolverControl by setting reduce
to zero.
Definition at line 250 of file solver_control.cc.
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static |
Interface to parameter file.
Definition at line 299 of file solver_control.cc.
void ReductionControl::parse_parameters | ( | ParameterHandler & | param | ) |
Read parameters from file.
Definition at line 307 of file solver_control.cc.
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overridevirtual |
Decide about success or failure of an iteration. This function calls the one in the base class, but sets the tolerance to reduction * initial value
upon the first iteration.
Reimplemented from SolverControl.
Definition at line 260 of file solver_control.cc.
double ReductionControl::reduction | ( | ) | const |
Reduction factor.
double ReductionControl::set_reduction | ( | const double | ) |
Change reduction factor.
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inherited |
Return the result of the last check operation.
Definition at line 108 of file solver_control.cc.
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inherited |
Return the initial convergence criterion.
Definition at line 115 of file solver_control.cc.
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inherited |
Return the convergence value of last iteration step for which check
was called by the solver.
Definition at line 122 of file solver_control.cc.
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inherited |
Number of last iteration step.
Definition at line 129 of file solver_control.cc.
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inherited |
Maximum number of steps.
Change maximum number of steps.
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inherited |
Enables the failure check. Solving is stopped with ReturnState
failure
if residual>failure_residual
with failure_residual := rel_failure_residual*first_residual
.
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inherited |
Disables failure check and resets relative_failure_residual
and failure_residual
to zero.
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inherited |
Tolerance.
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inherited |
Change tolerance.
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inherited |
Enables writing residuals of each step into a vector for later analysis.
Definition at line 147 of file solver_control.cc.
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inherited |
Provide read access to the collected residual data.
Definition at line 155 of file solver_control.cc.
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inherited |
Average error reduction over all steps.
Requires enable_history_data()
Definition at line 171 of file solver_control.cc.
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inherited |
Error reduction of the last step; for stationary iterations, this approximates the norm of the iteration matrix.
Requires enable_history_data()
Definition at line 199 of file solver_control.cc.
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inherited |
Error reduction of any iteration step.
Requires enable_history_data()
Definition at line 187 of file solver_control.cc.
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inherited |
Log each iteration step. Use log_frequency
for skipping steps.
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inherited |
Return the log_history
flag.
Set logging frequency.
Definition at line 136 of file solver_control.cc.
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inherited |
Log start and end step.
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inherited |
Return the log_result
flag.
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inherited |
Subscribes a user of the object by storing the pointer validity
. The subscriber may be identified by text supplied as identifier
.
Definition at line 130 of file subscriptor.cc.
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inherited |
Unsubscribes a user from the object.
identifier
and the validity
pointer must be the same as the one supplied to subscribe(). Definition at line 150 of file subscriptor.cc.
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inlineinherited |
Return the present number of subscriptions to this object. This allows to use this class for reference counted lifetime determination where the last one to unsubscribe also deletes the object.
Definition at line 301 of file subscriptor.h.
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inlineinherited |
List the subscribers to the input stream
.
Definition at line 318 of file subscriptor.h.
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inherited |
List the subscribers to deallog
.
Definition at line 198 of file subscriptor.cc.
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inlineinherited |
Read or write the data of this object to or from a stream for the purpose of serialization using the BOOST serialization library.
This function does not actually serialize any of the member variables of this class. The reason is that what this class stores is only who subscribes to this object, but who does so at the time of storing the contents of this object does not necessarily have anything to do with who subscribes to the object when it is restored. Consequently, we do not want to overwrite the subscribers at the time of restoring, and then there is no reason to write the subscribers out in the first place.
Definition at line 310 of file subscriptor.h.
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privatenoexceptinherited |
Check that there are no objects subscribing to this object. If this check passes then it is safe to destroy the current object. It this check fails then this function will either abort or print an error message to deallog (by using the AssertNothrow mechanism), but will not throw an exception.
Definition at line 52 of file subscriptor.cc.
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protected |
Desired reduction factor.
Definition at line 492 of file solver_control.h.
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protected |
Reduced tolerance. Stop iterations if either this value is achieved or if the base class indicates success.
Definition at line 498 of file solver_control.h.
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protectedinherited |
Maximum number of steps.
Definition at line 334 of file solver_control.h.
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protectedinherited |
Prescribed tolerance to be achieved.
Definition at line 339 of file solver_control.h.
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protectedinherited |
Result of last check operation.
Definition at line 344 of file solver_control.h.
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protectedinherited |
Initial value.
Definition at line 349 of file solver_control.h.
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protectedinherited |
Last value of the convergence criterion.
Definition at line 354 of file solver_control.h.
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protectedinherited |
Last step.
Definition at line 359 of file solver_control.h.
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protectedinherited |
Is set to true
by set_failure_criterion
and enables failure checking.
Definition at line 365 of file solver_control.h.
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protectedinherited |
Stores the rel_failure_residual
set by set_failure_criterion
Definition at line 370 of file solver_control.h.
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protectedinherited |
failure_residual
equals the first residual multiplied by relative_crit
set by set_failure_criterion
(see there).
Until the first residual is known it is 0.
Definition at line 378 of file solver_control.h.
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protectedinherited |
Log convergence history to deallog
.
Definition at line 383 of file solver_control.h.
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protectedinherited |
Log only every nth step.
Definition at line 388 of file solver_control.h.
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protectedinherited |
Log iteration result to deallog
. If true, after finishing the iteration, a statement about failure or success together with lstep
and lvalue
are logged.
Definition at line 395 of file solver_control.h.
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protectedinherited |
Control over the storage of history data. Set by enable_history_data().
Definition at line 400 of file solver_control.h.
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protectedinherited |
Vector storing the result after each iteration step for later statistical analysis.
Use of this vector is enabled by enable_history_data().
Definition at line 408 of file solver_control.h.
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mutableprivateinherited |
Store the number of objects which subscribed to this object. Initially, this number is zero, and upon destruction it shall be zero again (i.e. all objects which subscribed should have unsubscribed again).
The creator (and owner) of an object is counted in the map below if HE manages to supply identification.
We use the mutable
keyword in order to allow subscription to constant objects also.
This counter may be read from and written to concurrently in multithreaded code: hence we use the std::atomic
class template.
Definition at line 219 of file subscriptor.h.
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mutableprivateinherited |
In this map, we count subscriptions for each different identification string supplied to subscribe().
Definition at line 225 of file subscriptor.h.
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mutableprivateinherited |
In this vector, we store pointers to the validity bool in the ObserverPointer objects that subscribe to this class.
Definition at line 241 of file subscriptor.h.
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mutableprivateinherited |
Pointer to the typeinfo object of this object, from which we can later deduce the class name. Since this information on the derived class is neither available in the destructor, nor in the constructor, we obtain it in between and store it here.
Definition at line 249 of file subscriptor.h.
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staticprivateinherited |
A mutex used to ensure data consistency when accessing the mutable
members of this class. This lock is used in the subscribe() and unsubscribe() functions, as well as in list_subscribers()
.
Definition at line 272 of file subscriptor.h.