Reference documentation for deal.II version GIT 1e9e64a91d 2022-09-28 19:20:02+00:00
NonMatching::MeshClassifier< dim > Class Template Reference

#include <deal.II/non_matching/mesh_classifier.h>

Inheritance diagram for NonMatching::MeshClassifier< dim >:
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## Public Member Functions

template<class VectorType >
MeshClassifier (const DoFHandler< dim > &level_set_dof_handler, const VectorType &level_set)

MeshClassifier (const Triangulation< dim > &triangulation, const Function< dim > &level_set, const FiniteElement< dim > &element)

void reclassify ()

LocationToLevelSet location_to_level_set (const typename Triangulation< dim >::cell_iterator &cell) const

LocationToLevelSet location_to_level_set (const typename Triangulation< dim >::cell_iterator &cell, const unsigned int face_index) 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 SmartPointer 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 ::ExceptionBaseExcInUse (int arg1, std::string arg2, std::string arg3)

static ::ExceptionBaseExcNoSubscriber (std::string arg1, std::string arg2)

## Private Types

using map_value_type = decltype(counter_map)::value_type

using map_iterator = decltype(counter_map)::iterator

## Private Member Functions

void initialize ()

LocationToLevelSet determine_face_location_to_levelset (const typename Triangulation< dim >::active_cell_iterator &cell, const unsigned int face_index)

void check_no_subscribers () const noexcept

## Private Attributes

const SmartPointer< const Triangulation< dim > > triangulation

const std::unique_ptr< internal::MeshClassifierImplementation::LevelSetDescription< dim > > level_set_description

std::vector< LocationToLevelSetcell_locations

std::vector< LocationToLevelSetface_locations

std::vector< std::array< LAPACKFullMatrix< double >, GeometryInfo< dim >::faces_per_cell > > lagrange_to_bernstein_face

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

## Detailed Description

### template<int dim> class NonMatching::MeshClassifier< dim >

Class responsible for determining how the active cells and faces of a triangulation relate to the sign of a level set function. When calling the reclassify() function each of the active cells and faces are categorized as one of the values of LocationToLevelSet: inside, outside or intersected, depending on the sign of the level set function over the cell/face. This information is typically required in immersed/cut finite element methods, both when distributing degrees of freedom over the triangulation and when the system is assembled. The given class would then be used in the following way:

Vector<double> &level_set = ...
MeshClassifier<dim> classifier(dof_handler, level_set);
classifier.reclassify();
LocationToLevelSet location = classifier.location_to_level_set(cell);

The level set function can either be described as a discrete function by a (DoFHandler, Vector)-pair or as a general Function. In the case of a discrete function, LocationToLevelSet for a given face is determined by looking at the local degrees of freedom on the face. Since the Lagrange basis functions are not positive definite, positive/negative definite dof values do not imply that the interpolated function is positive/negative definite. Thus, to classify a face this class internally transforms the local dofs to a basis spanning the same polynomial space over the face but where definite dof values imply a definite function. Currently, only the case of FE_Q-elements is implemented, where we internally change basis to FE_Bernstein. For cells, LocationToLevelSet is determined from the faces of the cell. That is, if all faces of the cell are inside/outside the LocationToLevelSet of the cell is set to inside/outside. LocationToLevelSet of the cell is set to intersected if at least one face is intersected or if its faces have different LocationToLevelSet. Note that, this procedure will incorrectly classify the cell as inside/outside, if the mesh refinement is so low that the whole zero-contour is contained in a single cell (so that none of its faces are intersected).

When the level set function is described as a Function, the level set function is locally interpolated to an FE_Q element and we proceed in the same way as for the discrete level set function.

Definition at line 109 of file mesh_classifier.h.

## ◆ map_value_type

 using Subscriptor::map_value_type = decltype(counter_map)::value_type
privateinherited

The data type used in counter_map.

Definition at line 230 of file subscriptor.h.

## ◆ map_iterator

 using Subscriptor::map_iterator = decltype(counter_map)::iterator
privateinherited

The iterator type used in counter_map.

Definition at line 235 of file subscriptor.h.

## ◆ MeshClassifier() [1/2]

template<int dim>
template<class VectorType >
 NonMatching::MeshClassifier< dim >::MeshClassifier ( const DoFHandler< dim > & level_set_dof_handler, const VectorType & level_set )

Constructor. Takes a level set function described as a DoFHandler and a Vector. The triangulation attached to DoFHandler is the one that will be classified.

Definition at line 315 of file mesh_classifier.cc.

## ◆ MeshClassifier() [2/2]

template<int dim>
 NonMatching::MeshClassifier< dim >::MeshClassifier ( const Triangulation< dim > & triangulation, const Function< dim > & level_set, const FiniteElement< dim > & element )

Constructor. Takes the triangulation that should be classified, a level set function described as a Function, and a scalar element that we interpolate the Function to in order to classify each cell/face.

Note
The Function and the FiniteElement must both have a single component.

Definition at line 345 of file mesh_classifier.cc.

## ◆ reclassify()

template<int dim>
 void NonMatching::MeshClassifier< dim >::reclassify

Perform the classification of the non artificial cells and faces in the triangulation.

Definition at line 363 of file mesh_classifier.cc.

## ◆ location_to_level_set() [1/2]

template<int dim>
 LocationToLevelSet NonMatching::MeshClassifier< dim >::location_to_level_set ( const typename Triangulation< dim >::cell_iterator & cell ) const

Return how the incoming cell is located relative to the level set function.

Definition at line 433 of file mesh_classifier.cc.

## ◆ location_to_level_set() [2/2]

template<int dim>
 LocationToLevelSet NonMatching::MeshClassifier< dim >::location_to_level_set ( const typename Triangulation< dim >::cell_iterator & cell, const unsigned int face_index ) const

Return how a face of the incoming cell is located relative to the level set function.

Definition at line 448 of file mesh_classifier.cc.

## ◆ initialize()

template<int dim>
 void NonMatching::MeshClassifier< dim >::initialize
private

For each element in the hp::FECollection returned by level_set_description, sets up the local transformation matrices.

Definition at line 465 of file mesh_classifier.cc.

## ◆ determine_face_location_to_levelset()

template<int dim>
 LocationToLevelSet NonMatching::MeshClassifier< dim >::determine_face_location_to_levelset ( const typename Triangulation< dim >::active_cell_iterator & cell, const unsigned int face_index )
private

Computes how the face with the given index on the incoming cell is located relative to the level set function.

Definition at line 400 of file mesh_classifier.cc.

## ◆ subscribe()

 void Subscriptor::subscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const
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 136 of file subscriptor.cc.

## ◆ unsubscribe()

 void Subscriptor::unsubscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const
inherited

Unsubscribes a user from the object.

Note
The identifier and the validity pointer must be the same as the one supplied to subscribe().

Definition at line 156 of file subscriptor.cc.

## ◆ n_subscriptions()

 unsigned int Subscriptor::n_subscriptions ( ) const
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 300 of file subscriptor.h.

## ◆ list_subscribers() [1/2]

template<typename StreamType >
 void Subscriptor::list_subscribers ( StreamType & stream ) const
inlineinherited

List the subscribers to the input stream.

Definition at line 317 of file subscriptor.h.

## ◆ list_subscribers() [2/2]

 void Subscriptor::list_subscribers ( ) const
inherited

List the subscribers to deallog.

Definition at line 204 of file subscriptor.cc.

## ◆ serialize()

template<class Archive >
 void Subscriptor::serialize ( Archive & ar, const unsigned int version )
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 309 of file subscriptor.h.

## ◆ check_no_subscribers()

 void Subscriptor::check_no_subscribers ( ) const
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.

Note
Since this function is just a consistency check it does nothing in release mode.
If this function is called when there is an uncaught exception then, rather than aborting, this function prints an error message to the standard error stream and returns.

Definition at line 53 of file subscriptor.cc.

## ◆ triangulation

template<int dim>
 const SmartPointer > NonMatching::MeshClassifier< dim >::triangulation
private

Pointer to the triangulation that should be classified.

Definition at line 176 of file mesh_classifier.h.

## ◆ level_set_description

template<int dim>
 const std::unique_ptr< internal::MeshClassifierImplementation::LevelSetDescription > NonMatching::MeshClassifier< dim >::level_set_description
private

Pointer to an object that describes what we need to know about the level set function. The underlying object will be of different type depending on whether the level set function is discrete (DoFHandler, Vector) or described by a Function.

Definition at line 186 of file mesh_classifier.h.

## ◆ cell_locations

template<int dim>
 std::vector NonMatching::MeshClassifier< dim >::cell_locations
private

A vector that stores how each active cell is located relative to the level set function, based on the cells active index.

Definition at line 192 of file mesh_classifier.h.

## ◆ face_locations

template<int dim>
 std::vector NonMatching::MeshClassifier< dim >::face_locations
private

A vector that stores how each active face is located relative to the level set function, based on the face's global index.

Definition at line 198 of file mesh_classifier.h.

## ◆ lagrange_to_bernstein_face

template<int dim>
 std::vector< std::array, GeometryInfo::faces_per_cell> > NonMatching::MeshClassifier< dim >::lagrange_to_bernstein_face
private

For each element in the hp::FECollection returned by the LevelSetDescription, and for each local face, this vector stores a transformation matrix to a basis where positive/negative definite face dofs implies that the underlying function is positive/negative definite over the face.

Definition at line 209 of file mesh_classifier.h.

## ◆ counter

 std::atomic Subscriptor::counter
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.

## ◆ counter_map

 std::map Subscriptor::counter_map
mutableprivateinherited

In this map, we count subscriptions for each different identification string supplied to subscribe().

Definition at line 225 of file subscriptor.h.

## ◆ validity_pointers

 std::vector *> Subscriptor::validity_pointers
mutableprivateinherited

In this vector, we store pointers to the validity bool in the SmartPointer objects that subscribe to this class.

Definition at line 241 of file subscriptor.h.

## ◆ object_info

 const std::type_info* Subscriptor::object_info
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.

## ◆ mutex

 std::mutex Subscriptor::mutex
staticprivateinherited

A mutex used to ensure data consistency when printing out the list of subscribers.

Definition at line 271 of file subscriptor.h.

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