Reference documentation for deal.II version GIT d77e5ebb0a 2023-01-27 22:35:02+00:00
MappingQCache< dim, spacedim > Class Template Reference

#include <deal.II/fe/mapping_q_cache.h>

Inheritance diagram for MappingQCache< dim, spacedim >:
[legend]

## Public Member Functions

MappingQCache (const unsigned int polynomial_degree)

MappingQCache (const MappingQCache< dim, spacedim > &mapping)

~MappingQCache ()

virtual std::unique_ptr< Mapping< dim, spacedim > > clone () const override

virtual bool preserves_vertex_locations () const override

void initialize (const Mapping< dim, spacedim > &mapping, const Triangulation< dim, spacedim > &triangulation)

void initialize (const Triangulation< dim, spacedim > &triangulation, const MappingQ< dim, spacedim > &mapping)

void initialize (const Triangulation< dim, spacedim > &triangulation, const std::function< std::vector< Point< spacedim >>(const typename Triangulation< dim, spacedim >::cell_iterator &)> &compute_points_on_cell)

void initialize (const Mapping< dim, spacedim > &mapping, const Triangulation< dim, spacedim > &tria, const std::function< Point< spacedim >(const typename Triangulation< dim, spacedim >::cell_iterator &, const Point< spacedim > &)> &transformation_function, const bool function_describes_relative_displacement)

void initialize (const Mapping< dim, spacedim > &mapping, const Triangulation< dim, spacedim > &tria, const Function< spacedim > &transformation_function, const bool function_describes_relative_displacement)

template<typename VectorType >
void initialize (const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof_handler, const VectorType &vector, const bool vector_describes_relative_displacement)

template<typename VectorType >
void initialize (const Mapping< dim, spacedim > &mapping, const DoFHandler< dim, spacedim > &dof_handler, const MGLevelObject< VectorType > &vectors, const bool vector_describes_relative_displacement)

virtual boost::container::small_vector< Point< spacedim >, GeometryInfo< dim >::vertices_per_cell > get_vertices (const typename Triangulation< dim, spacedim >::cell_iterator &cell) const override

std::size_t memory_consumption () const

unsigned int get_degree () const

virtual BoundingBox< spacedim > get_bounding_box (const typename Triangulation< dim, spacedim >::cell_iterator &cell) const override

virtual bool is_compatible_with (const ReferenceCell &reference_cell) const override

void fill_mapping_data_for_generic_points (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const ArrayView< const Point< dim >> &unit_points, const UpdateFlags update_flags, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > &output_data) const

virtual Point< spacedim > get_center (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const bool map_center_of_reference_cell=true) const

template<class Archive >
void serialize (Archive &ar, const unsigned int version)

Mapping points between reference and real cells
virtual Point< spacedim > transform_unit_to_real_cell (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const Point< dim > &p) const override

virtual Point< dim > transform_real_to_unit_cell (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const Point< spacedim > &p) const override

virtual void transform_points_real_to_unit_cell (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const ArrayView< const Point< spacedim >> &real_points, const ArrayView< Point< dim >> &unit_points) const override

Functions to transform tensors from reference to real coordinates
virtual void transform (const ArrayView< const Tensor< 1, dim >> &input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase &internal, const ArrayView< Tensor< 1, spacedim >> &output) const override

virtual void transform (const ArrayView< const DerivativeForm< 1, dim, spacedim >> &input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase &internal, const ArrayView< Tensor< 2, spacedim >> &output) const override

virtual void transform (const ArrayView< const Tensor< 2, dim >> &input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase &internal, const ArrayView< Tensor< 2, spacedim >> &output) const override

virtual void transform (const ArrayView< const DerivativeForm< 2, dim, spacedim >> &input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase &internal, const ArrayView< Tensor< 3, spacedim >> &output) const override

virtual void transform (const ArrayView< const Tensor< 3, dim >> &input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase &internal, const ArrayView< Tensor< 3, spacedim >> &output) const override

Mapping points between reference and real cells
Point< dim - 1 > project_real_point_to_unit_point_on_face (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const unsigned int face_no, const Point< spacedim > &p) const

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)

Exceptions
static ::ExceptionBaseExcInvalidData ()

static ::ExceptionBaseExcTransformationFailed ()

static ::ExceptionBaseExcDistortedMappedCell (Point< spacedim > arg1, double arg2, int arg3)

## Protected Member Functions

virtual std::vector< Point< spacedim > > compute_mapping_support_points (const typename Triangulation< dim, spacedim >::cell_iterator &cell) const override

Point< dim > transform_real_to_unit_cell_internal (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const Point< spacedim > &p, const Point< dim > &initial_p_unit) const

Point< 1 > transform_real_to_unit_cell_internal (const Triangulation< 1, 1 >::cell_iterator &cell, const Point< 1 > &p, const Point< 1 > &initial_p_unit) const

Point< 2 > transform_real_to_unit_cell_internal (const Triangulation< 2, 2 >::cell_iterator &cell, const Point< 2 > &p, const Point< 2 > &initial_p_unit) const

Point< 3 > transform_real_to_unit_cell_internal (const Triangulation< 3, 3 >::cell_iterator &cell, const Point< 3 > &p, const Point< 3 > &initial_p_unit) const

Point< 1 > transform_real_to_unit_cell_internal (const Triangulation< 1, 2 >::cell_iterator &cell, const Point< 2 > &p, const Point< 1 > &initial_p_unit) const

Point< 2 > transform_real_to_unit_cell_internal (const Triangulation< 2, 3 >::cell_iterator &cell, const Point< 3 > &p, const Point< 2 > &initial_p_unit) const

Point< 1 > transform_real_to_unit_cell_internal (const Triangulation< 1, 3 >::cell_iterator &, const Point< 3 > &, const Point< 1 > &) const

virtual void add_line_support_points (const typename Triangulation< dim, spacedim >::cell_iterator &cell, std::vector< Point< spacedim >> &a) const

virtual void add_quad_support_points (const typename Triangulation< dim, spacedim >::cell_iterator &cell, std::vector< Point< spacedim >> &a) const

void add_quad_support_points (const Triangulation< 3, 3 >::cell_iterator &cell, std::vector< Point< 3 >> &a) const

void add_quad_support_points (const Triangulation< 2, 3 >::cell_iterator &cell, std::vector< Point< 3 >> &a) const

Interface with FEValues and friends
virtual UpdateFlags requires_update_flags (const UpdateFlags update_flags) const override

virtual std::unique_ptr< typename Mapping< dim, spacedim >::InternalDataBase > get_data (const UpdateFlags, const Quadrature< dim > &quadrature) const override

virtual std::unique_ptr< typename Mapping< dim, spacedim >::InternalDataBase > get_face_data (const UpdateFlags flags, const hp::QCollection< dim - 1 > &quadrature) const override

virtual std::unique_ptr< typename Mapping< dim, spacedim >::InternalDataBase > get_subface_data (const UpdateFlags flags, const Quadrature< dim - 1 > &quadrature) const override

virtual CellSimilarity::Similarity fill_fe_values (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const CellSimilarity::Similarity cell_similarity, const Quadrature< dim > &quadrature, const typename Mapping< dim, spacedim >::InternalDataBase &internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > &output_data) const override

virtual void fill_fe_face_values (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const unsigned int face_no, const hp::QCollection< dim - 1 > &quadrature, const typename Mapping< dim, spacedim >::InternalDataBase &internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > &output_data) const override

virtual void fill_fe_subface_values (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const unsigned int face_no, const unsigned int subface_no, const Quadrature< dim - 1 > &quadrature, const typename Mapping< dim, spacedim >::InternalDataBase &internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > &output_data) const override

virtual void fill_fe_immersed_surface_values (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const NonMatching::ImmersedSurfaceQuadrature< dim > &quadrature, const typename Mapping< dim, spacedim >::InternalDataBase &internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > &output_data) const override

Interface with FEValues
virtual std::unique_ptr< InternalDataBase > get_face_data (const UpdateFlags update_flags, const Quadrature< dim - 1 > &quadrature) const

virtual void fill_fe_face_values (const typename Triangulation< dim, spacedim >::cell_iterator &cell, const unsigned int face_no, const Quadrature< dim - 1 > &quadrature, const typename Mapping< dim, spacedim >::InternalDataBase &internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > &output_data) const

## Protected Attributes

const unsigned int polynomial_degree

const std::vector< Point< 1 > > line_support_points

const std::vector< Polynomials::Polynomial< double > > polynomials_1d

const std::vector< unsigned int > renumber_lexicographic_to_hierarchic

const std::vector< Point< dim > > unit_cell_support_points

const std::vector< Table< 2, double > > support_point_weights_perimeter_to_interior

const Table< 2, doublesupport_point_weights_cell

## 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::shared_ptr< std::vector< std::vector< std::vector< Point< spacedim > > > > > support_point_cache

boost::signals2::connection clear_signal

bool uses_level_info

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, int spacedim = dim> class MappingQCache< dim, spacedim >

This class implements a caching strategy for objects of the MappingQ family in terms of the MappingQ::compute_mapping_support_points() function, which is used in all operations of MappingQ. The information of the mapping is pre-computed by the MappingQCache::initialize() function.

The use of this class is discussed extensively in step-65.

Definition at line 53 of file mapping_q_cache.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.

## ◆ MappingQCache() [1/2]

template<int dim, int spacedim>
 MappingQCache< dim, spacedim >::MappingQCache ( const unsigned int polynomial_degree )
explicit

Constructor. polynomial_degree denotes the polynomial degree of the polynomials that are used to map cells from the reference to the real cell.

Definition at line 39 of file mapping_q_cache.cc.

## ◆ MappingQCache() [2/2]

template<int dim, int spacedim>
 MappingQCache< dim, spacedim >::MappingQCache ( const MappingQCache< dim, spacedim > & mapping )
explicit

Copy constructor.

Definition at line 48 of file mapping_q_cache.cc.

## ◆ ~MappingQCache()

template<int dim, int spacedim>
 MappingQCache< dim, spacedim >::~MappingQCache

Destructor.

Definition at line 58 of file mapping_q_cache.cc.

## ◆ clone()

template<int dim, int spacedim>
 std::unique_ptr< Mapping< dim, spacedim > > MappingQCache< dim, spacedim >::clone
overridevirtual

clone() functionality. For documentation, see Mapping::clone().

Reimplemented from MappingQ< dim, dim >.

Definition at line 72 of file mapping_q_cache.cc.

## ◆ preserves_vertex_locations()

template<int dim, int spacedim>
 bool MappingQCache< dim, spacedim >::preserves_vertex_locations
overridevirtual

Returns false because the preservation of vertex locations depends on the mapping handed to the reinit() function.

Reimplemented from MappingQ< dim, dim >.

Definition at line 81 of file mapping_q_cache.cc.

## ◆ initialize() [1/7]

template<int dim, int spacedim>
 void MappingQCache< dim, spacedim >::initialize ( const Mapping< dim, spacedim > & mapping, const Triangulation< dim, spacedim > & triangulation )

Initialize the data cache by computing the mapping support points for all cells (on all levels) of the given triangulation.

Note
The cache is invalidated upon the signal Triangulation::Signals::any_change of the underlying triangulation.

Definition at line 90 of file mapping_q_cache.cc.

## ◆ initialize() [2/7]

template<int dim, int spacedim>
 void MappingQCache< dim, spacedim >::initialize ( const Triangulation< dim, spacedim > & triangulation, const MappingQ< dim, spacedim > & mapping )

Initialize the data cache by computing the mapping support points for all cells (on all levels) of the given triangulation.

Note
The cache is invalidated upon the signal Triangulation::Signals::any_change of the underlying triangulation.
Deprecated:

Definition at line 139 of file mapping_q_cache.cc.

## ◆ initialize() [3/7]

template<int dim, int spacedim>
 void MappingQCache< dim, spacedim >::initialize ( const Triangulation< dim, spacedim > & triangulation, const std::function< std::vector< Point< spacedim >>(const typename Triangulation< dim, spacedim >::cell_iterator &)> & compute_points_on_cell )

Initialize the data cache by letting the function given as an argument provide the mapping support points for all cells (on all levels) of the given triangulation. The function must return a vector of Point<spacedim> whose length is the same as the size of the polynomial space, $$(p+1)^\text{dim}$$, where $$p$$ is the polynomial degree of the mapping, and it must be in the order the mapping or FE_Q sort their points, i.e., all $$2^\text{dim}$$ vertex points first, then the points on the lines, quads, and hexes according to the usual hierarchical numbering. No attempt is made to validate these points internally, except for the number of given points.

Note
If multiple threads are enabled, this function will run in parallel, invoking the function passed in several times. Thus, in case MultithreadInfo::n_threads()>1, the user code must make sure that the function, typically a lambda, does not write into data shared with other threads.
The cache is invalidated upon the signal Triangulation::Signals::any_change of the underlying triangulation.

Definition at line 150 of file mapping_q_cache.cc.

## ◆ initialize() [4/7]

template<int dim, int spacedim>
 void MappingQCache< dim, spacedim >::initialize ( const Mapping< dim, spacedim > & mapping, const Triangulation< dim, spacedim > & tria, const std::function< Point< spacedim >(const typename Triangulation< dim, spacedim >::cell_iterator &, const Point< spacedim > &)> & transformation_function, const bool function_describes_relative_displacement )

Initialize the data cache by computing the mapping support points for all cells (on all levels) of the given triangulation and a given mapping and transforming these points via the function transformation_function.

The bool function_describes_relative_displacement indicates that the function transformation_function maps to absolute coordinates. If the parameter is set to true, the return value of the function is interpreted as relative deformation and the result is eventually added to the original point for the support points eventually used by this class.

This function calls the previous function so the comments regarding threading listed above apply also here.

Note
The cache is invalidated upon the signal Triangulation::Signals::any_change of the underlying triangulation.

Definition at line 191 of file mapping_q_cache.cc.

## ◆ initialize() [5/7]

template<int dim, int spacedim>
 void MappingQCache< dim, spacedim >::initialize ( const Mapping< dim, spacedim > & mapping, const Triangulation< dim, spacedim > & tria, const Function< spacedim > & transformation_function, const bool function_describes_relative_displacement )

The same as above but taking a Function object.

Definition at line 257 of file mapping_q_cache.cc.

## ◆ initialize() [6/7]

template<int dim, int spacedim>
template<typename VectorType >
 void MappingQCache< dim, spacedim >::initialize ( const Mapping< dim, spacedim > & mapping, const DoFHandler< dim, spacedim > & dof_handler, const VectorType & vector, const bool vector_describes_relative_displacement )

Initialize the data cache of the active cells by a discrete field (specified by dof_handler and vector) that describes the absolute or relative position of each support point.

Note
By using this function for reinitialization, this class behaves like MappingFEField (vector_describes_relative_displacement == false) or MappingQEulerian (vector_describes_relative_displacement == true), but with much more efficient operations internally.

Definition at line 302 of file mapping_q_cache.cc.

## ◆ initialize() [7/7]

template<int dim, int spacedim>
template<typename VectorType >
 void MappingQCache< dim, spacedim >::initialize ( const Mapping< dim, spacedim > & mapping, const DoFHandler< dim, spacedim > & dof_handler, const MGLevelObject< VectorType > & vectors, const bool vector_describes_relative_displacement )

Initialize the data cache of all non-artificial cells by a solution (specified by dof_handler and a set of vectors on all levels of the triangulation) that describes the absolute or relative position of each support point.

Note
By using this function for reinitialization, this class behaves like MappingFEField (vector_describes_relative_displacement == false) or MappingQEulerian (vector_describes_relative_displacement == true), but with much more efficient operations internally.

Definition at line 498 of file mapping_q_cache.cc.

## ◆ get_vertices()

template<int dim, int spacedim>
 boost::container::small_vector< Point< spacedim >, GeometryInfo< dim >::vertices_per_cell > MappingQCache< dim, spacedim >::get_vertices ( const typename Triangulation< dim, spacedim >::cell_iterator & cell ) const
overridevirtual

Return the mapped vertices of a cell.

Most of the time, these values will simply be the coordinates of the vertices of a cell as returned by cell->vertex(v) for vertex v, i.e., information stored by the triangulation. However, there are also mappings that add displacements or choose completely different locations, e.g., MappingQEulerian, MappingQ1Eulerian, or MappingFEField.

The default implementation of this function simply returns the information stored by the triangulation, i.e., cell->vertex(v).

Reimplemented from Mapping< dim, spacedim >.

Definition at line 743 of file mapping_q_cache.cc.

## ◆ memory_consumption()

template<int dim, int spacedim>
 std::size_t MappingQCache< dim, spacedim >::memory_consumption

Return the memory consumption (in bytes) of the cache.

Definition at line 711 of file mapping_q_cache.cc.

## ◆ compute_mapping_support_points()

template<int dim, int spacedim>
 std::vector< Point< spacedim > > MappingQCache< dim, spacedim >::compute_mapping_support_points ( const typename Triangulation< dim, spacedim >::cell_iterator & cell ) const
overrideprotectedvirtual

This is the main function overridden from the base class MappingQ.

Reimplemented from MappingQ< dim, dim >.

Definition at line 724 of file mapping_q_cache.cc.

## ◆ get_degree()

 unsigned int MappingQ< dim, spacedim >::get_degree
inherited

Return the degree of the mapping, i.e. the value which was passed to the constructor.

Definition at line 144 of file mapping_q.cc.

## ◆ get_bounding_box()

 BoundingBox< spacedim > MappingQ< dim, spacedim >::get_bounding_box ( const typename Triangulation< dim, spacedim >::cell_iterator & cell ) const
overridevirtualinherited

Return the bounding box of a mapped cell.

If you are using a (bi-,tri-)linear mapping that preserves vertex locations, this function simply returns the value also produced by cell->bounding_box(). However, there are also mappings that add displacements or choose completely different locations, e.g., MappingQEulerian, MappingQ1Eulerian, or MappingFEField.

For linear mappings, this function returns the bounding box containing all the vertices of the cell, as returned by the get_vertices() method. For higher order mappings defined through support points, the bounding box is only guaranteed to contain all the support points, and it is, in general, only an approximation of the true bounding box, which may be larger.

Parameters
 [in] cell The cell for which you want to compute the bounding box

Reimplemented from Mapping< dim, spacedim >.

Definition at line 155 of file mapping_q.cc.

## ◆ is_compatible_with()

 bool MappingQ< dim, spacedim >::is_compatible_with ( const ReferenceCell & reference_cell ) const
overridevirtualinherited

Returns if this instance of Mapping is compatible with the type of cell in reference_cell.

Implements Mapping< dim, spacedim >.

Definition at line 159 of file mapping_q.cc.

## ◆ transform_unit_to_real_cell()

 Point< spacedim > MappingQ< dim, spacedim >::transform_unit_to_real_cell ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const Point< dim > & p ) const
overridevirtualinherited

Map the point p on the unit cell to the corresponding point on the real cell cell.

Parameters
 cell Iterator to the cell that will be used to define the mapping. p Location of a point on the reference cell.
Returns
The location of the reference point mapped to real space using the mapping defined by the class derived from the current one that implements the mapping, and the coordinates of the cell identified by the first argument.

Implements Mapping< dim, spacedim >.

Definition at line 168 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell()

 Point< dim > MappingQ< dim, spacedim >::transform_real_to_unit_cell ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const Point< spacedim > & p ) const
overridevirtualinherited

Map the point p on the real cell to the corresponding point on the unit cell, and return its coordinates. This function provides the inverse of the mapping provided by transform_unit_to_real_cell().

In the codimension one case, this function returns the normal projection of the real point p on the curve or surface identified by the cell.

Note
Polynomial mappings from the reference (unit) cell coordinates to the coordinate system of a real cell are not always invertible if the point for which the inverse mapping is to be computed lies outside the cell's boundaries. In such cases, the current function may fail to compute a point on the reference cell whose image under the mapping equals the given point p. If this is the case then this function throws an exception of type Mapping::ExcTransformationFailed . Whether the given point p lies outside the cell can therefore be determined by checking whether the returned reference coordinates lie inside or outside the reference cell (e.g., using GeometryInfo::is_inside_unit_cell()) or whether the exception mentioned above has been thrown.
Parameters
 cell Iterator to the cell that will be used to define the mapping. p Location of a point on the given cell.
Returns
The reference cell location of the point that when mapped to real space equals the coordinates given by the second argument. This mapping uses the mapping defined by the class derived from the current one that implements the mapping, and the coordinates of the cell identified by the first argument.

Implements Mapping< dim, spacedim >.

Definition at line 174 of file mapping_q.cc.

## ◆ transform_points_real_to_unit_cell()

 void MappingQ< dim, spacedim >::transform_points_real_to_unit_cell ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const ArrayView< const Point< spacedim >> & real_points, const ArrayView< Point< dim >> & unit_points ) const
overridevirtualinherited

Map multiple points from the real point locations to points in reference locations. The functionality is essentially the same as looping over all points and calling the Mapping::transform_real_to_unit_cell() function for each point individually, but it can be much faster for certain mappings that implement a more specialized version such as MappingQ. The only difference in behavior is that this function will never throw an ExcTransformationFailed() exception. If the transformation fails for real_points[i], the returned unit_points[i] contains std::numeric_limits<double>::infinity() as the first entry.

Reimplemented from Mapping< dim, spacedim >.

Definition at line 180 of file mapping_q.cc.

## ◆ transform() [1/5]

 void MappingQ< dim, spacedim >::transform ( const ArrayView< const Tensor< 1, dim >> & input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase & internal, const ArrayView< Tensor< 1, spacedim >> & output ) const
overridevirtualinherited

Transform a field of vectors or 1-differential forms according to the selected MappingKind.

Note
Normally, this function is called by a finite element, filling FEValues objects. For this finite element, there should be an alias MappingKind like mapping_bdm, mapping_nedelec, etc. This alias should be preferred to using the kinds below.

The mapping kinds currently implemented by derived classes are:

• mapping_contravariant: maps a vector field on the reference cell to the physical cell through the Jacobian:

$\mathbf u(\mathbf x) = J(\hat{\mathbf x})\hat{\mathbf u}(\hat{\mathbf x}).$

In physics, this is usually referred to as the contravariant transformation. Mathematically, it is the push forward of a vector field.

• mapping_covariant: maps a field of one-forms on the reference cell to a field of one-forms on the physical cell. (Theoretically this would refer to a DerivativeForm<1,dim,1> but we canonically identify this type with a Tensor<1,dim>). Mathematically, it is the pull back of the differential form

$\mathbf u(\mathbf x) = J(\hat{\mathbf x})(J(\hat{\mathbf x})^{T} J(\hat{\mathbf x}))^{-1}\hat{\mathbf u}(\hat{\mathbf x}).$

Gradients of scalar differentiable functions are transformed this way.

In the case when dim=spacedim the previous formula reduces to

$\mathbf u(\mathbf x) = J(\hat{\mathbf x})^{-T}\hat{\mathbf u}(\hat{\mathbf x})$

because we assume that the mapping $$\mathbf F_K$$ is always invertible, and consequently its Jacobian $$J$$ is an invertible matrix.

• mapping_piola: A field of dim-1-forms on the reference cell is also represented by a vector field, but again transforms differently, namely by the Piola transform

$\mathbf u(\mathbf x) = \frac{1}{\text{det}\;J(\hat{\mathbf x})} J(\hat{\mathbf x}) \hat{\mathbf u}(\hat{\mathbf x}).$

Parameters
 [in] input An array (or part of an array) of input objects that should be mapped. [in] kind The kind of mapping to be applied. [in] internal A pointer to an object of type Mapping::InternalDataBase that contains information previously stored by the mapping. The object pointed to was created by the get_data(), get_face_data(), or get_subface_data() function, and will have been updated as part of a call to fill_fe_values(), fill_fe_face_values(), or fill_fe_subface_values() for the current cell, before calling the current function. In other words, this object also represents with respect to which cell the transformation should be applied to. [out] output An array (or part of an array) into which the transformed objects should be placed. (Note that the array view is const, but the tensors it points to are not.)

Implements Mapping< dim, spacedim >.

Definition at line 196 of file mapping_q.cc.

## ◆ transform() [2/5]

 void MappingQ< dim, spacedim >::transform ( const ArrayView< const DerivativeForm< 1, dim, spacedim >> & input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase & internal, const ArrayView< Tensor< 2, spacedim >> & output ) const
overridevirtualinherited

Transform a field of differential forms from the reference cell to the physical cell. It is useful to think of $$\mathbf{T} = \nabla \mathbf u$$ and $$\hat{\mathbf T} = \hat \nabla \hat{\mathbf u}$$, with $$\mathbf u$$ a vector field. The mapping kinds currently implemented by derived classes are:

• mapping_covariant: maps a field of forms on the reference cell to a field of forms on the physical cell. Mathematically, it is the pull back of the differential form

$\mathbf T(\mathbf x) = \hat{\mathbf T}(\hat{\mathbf x}) J(\hat{\mathbf x})(J(\hat{\mathbf x})^{T} J(\hat{\mathbf x}))^{-1}.$

Jacobians of spacedim-vector valued differentiable functions are transformed this way.

In the case when dim=spacedim the previous formula reduces to

$\mathbf T(\mathbf x) = \hat{\mathbf u}(\hat{\mathbf x}) J(\hat{\mathbf x})^{-1}.$

Note
It would have been more reasonable to make this transform a template function with the rank in DerivativeForm<1, dim, rank>. Unfortunately C++ does not allow templatized virtual functions. This is why we identify DerivativeForm<1, dim, 1> with a Tensor<1,dim> when using mapping_covariant() in the function transform() above this one.
Parameters
 [in] input An array (or part of an array) of input objects that should be mapped. [in] kind The kind of mapping to be applied. [in] internal A pointer to an object of type Mapping::InternalDataBase that contains information previously stored by the mapping. The object pointed to was created by the get_data(), get_face_data(), or get_subface_data() function, and will have been updated as part of a call to fill_fe_values(), fill_fe_face_values(), or fill_fe_subface_values() for the current cell, before calling the current function. In other words, this object also represents with respect to which cell the transformation should be applied to. [out] output An array (or part of an array) into which the transformed objects should be placed. (Note that the array view is const, but the tensors it points to are not.)

Implements Mapping< dim, spacedim >.

Definition at line 203 of file mapping_q.cc.

## ◆ transform() [3/5]

 void MappingQ< dim, spacedim >::transform ( const ArrayView< const Tensor< 2, dim >> & input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase & internal, const ArrayView< Tensor< 2, spacedim >> & output ) const
overridevirtualinherited

Transform a tensor field from the reference cell to the physical cell. These tensors are usually the Jacobians in the reference cell of vector fields that have been pulled back from the physical cell. The mapping kinds currently implemented by derived classes are:

• mapping_contravariant_gradient: it assumes $$\mathbf u(\mathbf x) = J \hat{\mathbf u}$$ so that

$\mathbf T(\mathbf x) = J(\hat{\mathbf x}) \hat{\mathbf T}(\hat{\mathbf x}) J(\hat{\mathbf x})^{-1}.$

• mapping_covariant_gradient: it assumes $$\mathbf u(\mathbf x) = J^{-T} \hat{\mathbf u}$$ so that

$\mathbf T(\mathbf x) = J(\hat{\mathbf x})^{-T} \hat{\mathbf T}(\hat{\mathbf x}) J(\hat{\mathbf x})^{-1}.$

• mapping_piola_gradient: it assumes $$\mathbf u(\mathbf x) = \frac{1}{\text{det}\;J(\hat{\mathbf x})} J(\hat{\mathbf x}) \hat{\mathbf u}(\hat{\mathbf x})$$ so that

$\mathbf T(\mathbf x) = \frac{1}{\text{det}\;J(\hat{\mathbf x})} J(\hat{\mathbf x}) \hat{\mathbf T}(\hat{\mathbf x}) J(\hat{\mathbf x})^{-1}.$

Todo:
The formulas for mapping_covariant_gradient, mapping_contravariant_gradient and mapping_piola_gradient are only true as stated for linear mappings. If, for example, the mapping is bilinear (or has a higher order polynomial degree) then there is a missing term associated with the derivative of $$J$$.
Parameters
 [in] input An array (or part of an array) of input objects that should be mapped. [in] kind The kind of mapping to be applied. [in] internal A pointer to an object of type Mapping::InternalDataBase that contains information previously stored by the mapping. The object pointed to was created by the get_data(), get_face_data(), or get_subface_data() function, and will have been updated as part of a call to fill_fe_values(), fill_fe_face_values(), or fill_fe_subface_values() for the current cell, before calling the current function. In other words, this object also represents with respect to which cell the transformation should be applied to. [out] output An array (or part of an array) into which the transformed objects should be placed. (Note that the array view is const, but the tensors it points to are not.)

Implements Mapping< dim, spacedim >.

Definition at line 210 of file mapping_q.cc.

## ◆ transform() [4/5]

 void MappingQ< dim, spacedim >::transform ( const ArrayView< const DerivativeForm< 2, dim, spacedim >> & input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase & internal, const ArrayView< Tensor< 3, spacedim >> & output ) const
overridevirtualinherited

Transform a tensor field from the reference cell to the physical cell. This tensors are most of times the hessians in the reference cell of vector fields that have been pulled back from the physical cell.

The mapping kinds currently implemented by derived classes are:

• mapping_covariant_gradient: maps a field of forms on the reference cell to a field of forms on the physical cell. Mathematically, it is the pull back of the differential form

$\mathbf T_{ijk}(\mathbf x) = \hat{\mathbf T}_{iJK}(\hat{\mathbf x}) J_{jJ}^{\dagger} J_{kK}^{\dagger}$

,

where

$J^{\dagger} = J(\hat{\mathbf x})(J(\hat{\mathbf x})^{T} J(\hat{\mathbf x}))^{-1}.$

Hessians of spacedim-vector valued differentiable functions are transformed this way (After subtraction of the product of the derivative with the Jacobian gradient).

In the case when dim=spacedim the previous formula reduces to

$J^{\dagger} = J^{-1}$

Parameters
 [in] input An array (or part of an array) of input objects that should be mapped. [in] kind The kind of mapping to be applied. [in] internal A pointer to an object of type Mapping::InternalDataBase that contains information previously stored by the mapping. The object pointed to was created by the get_data(), get_face_data(), or get_subface_data() function, and will have been updated as part of a call to fill_fe_values(), fill_fe_face_values(), or fill_fe_subface_values() for the current cell, before calling the current function. In other words, this object also represents with respect to which cell the transformation should be applied to. [out] output An array (or part of an array) into which the transformed objects should be placed. (Note that the array view is const, but the tensors it points to are not.)

Implements Mapping< dim, spacedim >.

Definition at line 217 of file mapping_q.cc.

## ◆ transform() [5/5]

 void MappingQ< dim, spacedim >::transform ( const ArrayView< const Tensor< 3, dim >> & input, const MappingKind kind, const typename Mapping< dim, spacedim >::InternalDataBase & internal, const ArrayView< Tensor< 3, spacedim >> & output ) const
overridevirtualinherited

Transform a field of 3-differential forms from the reference cell to the physical cell. It is useful to think of $$\mathbf{T}_{ijk} = D^2_{jk} \mathbf u_i$$ and $$\mathbf{\hat T}_{IJK} = \hat D^2_{JK} \mathbf{\hat u}_I$$, with $$\mathbf u_i$$ a vector field.

The mapping kinds currently implemented by derived classes are:

• mapping_contravariant_hessian: it assumes $$\mathbf u_i(\mathbf x) = J_{iI} \hat{\mathbf u}_I$$ so that

$\mathbf T_{ijk}(\mathbf x) = J_{iI}(\hat{\mathbf x}) \hat{\mathbf T}_{IJK}(\hat{\mathbf x}) J_{jJ}(\hat{\mathbf x})^{-1} J_{kK}(\hat{\mathbf x})^{-1}.$

• mapping_covariant_hessian: it assumes $$\mathbf u_i(\mathbf x) = J_{iI}^{-T} \hat{\mathbf u}_I$$ so that

$\mathbf T_{ijk}(\mathbf x) = J_iI(\hat{\mathbf x})^{-1} \hat{\mathbf T}_{IJK}(\hat{\mathbf x}) J_{jJ}(\hat{\mathbf x})^{-1} J_{kK}(\hat{\mathbf x})^{-1}.$

• mapping_piola_hessian: it assumes $$\mathbf u_i(\mathbf x) = \frac{1}{\text{det}\;J(\hat{\mathbf x})} J_{iI}(\hat{\mathbf x}) \hat{\mathbf u}(\hat{\mathbf x})$$ so that

$\mathbf T_{ijk}(\mathbf x) = \frac{1}{\text{det}\;J(\hat{\mathbf x})} J_{iI}(\hat{\mathbf x}) \hat{\mathbf T}_{IJK}(\hat{\mathbf x}) J_{jJ}(\hat{\mathbf x})^{-1} J_{kK}(\hat{\mathbf x})^{-1}.$

Parameters
 [in] input An array (or part of an array) of input objects that should be mapped. [in] kind The kind of mapping to be applied. [in] internal A pointer to an object of type Mapping::InternalDataBase that contains information previously stored by the mapping. The object pointed to was created by the get_data(), get_face_data(), or get_subface_data() function, and will have been updated as part of a call to fill_fe_values(), fill_fe_face_values(), or fill_fe_subface_values() for the current cell, before calling the current function. In other words, this object also represents with respect to which cell the transformation should be applied to. [out] output An array (or part of an array) into which the transformed objects should be placed.

Implements Mapping< dim, spacedim >.

Definition at line 224 of file mapping_q.cc.

## ◆ fill_mapping_data_for_generic_points()

 void MappingQ< dim, spacedim >::fill_mapping_data_for_generic_points ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const ArrayView< const Point< dim >> & unit_points, const UpdateFlags update_flags, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > & output_data ) const
inherited

As opposed to the other fill_fe_values() and fill_fe_face_values() functions that rely on pre-computed information of InternalDataBase, this function chooses the flexible evaluation path on the cell and points passed in to the current function.

Parameters
 [in] cell The cell where to evaluate the mapping [in] unit_points The points in reference coordinates where the transformation (Jacobians, positions) should be computed. [in] update_flags The kind of information that should be computed. [out] output_data A struct containing the evaluated quantities such as the Jacobian resulting from application of the mapping on the given cell with its underlying manifolds.

Definition at line 251 of file mapping_q.cc.

## ◆ requires_update_flags()

 UpdateFlags MappingQ< dim, spacedim >::requires_update_flags ( const UpdateFlags update_flags ) const
overrideprotectedvirtualinherited

Given a set of update flags, compute which other quantities also need to be computed in order to satisfy the request by the given flags. Then return the combination of the original set of flags and those just computed.

As an example, if update_flags contains update_JxW_values (i.e., the product of the determinant of the Jacobian and the weights provided by the quadrature formula), a mapping may require the computation of the full Jacobian matrix in order to compute its determinant. They would then return not just update_JxW_values, but also update_jacobians. (This is not how it is actually done internally in the derived classes that compute the JxW values – they set update_contravariant_transformation instead, from which the determinant can also be computed – but this does not take away from the instructiveness of the example.)

An extensive discussion of the interaction between this function and FEValues can be found in the How Mapping, FiniteElement, and FEValues work together documentation module.

UpdateFlags

Implements Mapping< dim, spacedim >.

Definition at line 560 of file mapping_q.cc.

## ◆ get_data()

 std::unique_ptr< typename Mapping< dim, spacedim >::InternalDataBase > MappingQ< dim, spacedim >::get_data ( const UpdateFlags update_flags, const Quadrature< dim > & quadrature ) const
overrideprotectedvirtualinherited

Create and return a pointer to an object into which mappings can store data that only needs to be computed once but that can then be used whenever the mapping is applied to a concrete cell (e.g., in the various transform() functions, as well as in the fill_fe_values(), fill_fe_face_values() and fill_fe_subface_values() that form the interface of mappings with the FEValues class).

Derived classes will return pointers to objects of a type derived from Mapping::InternalDataBase (see there for more information) and may pre- compute some information already (in accordance with what will be asked of the mapping in the future, as specified by the update flags) and for the given quadrature object. Subsequent calls to transform() or fill_fe_values() and friends will then receive back the object created here (with the same set of update flags and for the same quadrature object). Derived classes can therefore pre-compute some information in their get_data() function and store it in the internal data object.

The mapping classes do not keep track of the objects created by this function. Ownership will therefore rest with the caller.

An extensive discussion of the interaction between this function and FEValues can be found in the How Mapping, FiniteElement, and FEValues work together documentation module.

Parameters
 update_flags A set of flags that define what is expected of the mapping class in future calls to transform() or the fill_fe_values() group of functions. This set of flags may contain flags that mappings do not know how to deal with (e.g., for information that is in fact computed by the finite element classes, such as UpdateFlags::update_values). Derived classes will need to store these flags, or at least that subset of flags that will require the mapping to perform any actions in fill_fe_values(), in InternalDataBase::update_each. quadrature The quadrature object for which mapping information will have to be computed. This includes the locations and weights of quadrature points.
Returns
A pointer to a newly created object of type InternalDataBase (or a derived class). Ownership of this object passes to the calling function.
Note
C++ allows that virtual functions in derived classes may return pointers to objects not of type InternalDataBase but in fact pointers to objects of classes derived from InternalDataBase. (This feature is called "covariant return types".) This is useful in some contexts where the calling is within the derived class and will immediately make use of the returned object, knowing its real (derived) type.

Implements Mapping< dim, spacedim >.

Definition at line 564 of file mapping_q.cc.

## ◆ get_face_data() [1/2]

 std::unique_ptr< typename Mapping< dim, spacedim >::InternalDataBase > MappingQ< dim, spacedim >::get_face_data ( const UpdateFlags update_flags, const hp::QCollection< dim - 1 > & quadrature ) const
overrideprotectedvirtualinherited

Like get_data(), but in preparation for later calls to transform() or fill_fe_face_values() that will need information about mappings from the reference face to a face of a concrete cell.

Parameters
 update_flags A set of flags that define what is expected of the mapping class in future calls to transform() or the fill_fe_values() group of functions. This set of flags may contain flags that mappings do not know how to deal with (e.g., for information that is in fact computed by the finite element classes, such as UpdateFlags::update_values). Derived classes will need to store these flags, or at least that subset of flags that will require the mapping to perform any actions in fill_fe_values(), in InternalDataBase::update_each. quadrature The quadrature object for which mapping information will have to be computed. This includes the locations and weights of quadrature points.
Returns
A pointer to a newly created object of type InternalDataBase (or a derived class). Ownership of this object passes to the calling function.
Note
C++ allows that virtual functions in derived classes may return pointers to objects not of type InternalDataBase but in fact pointers to objects of classes derived from InternalDataBase. (This feature is called "covariant return types".) This is useful in some contexts where the calling is within the derived class and will immediately make use of the returned object, knowing its real (derived) type.

Reimplemented from Mapping< dim, spacedim >.

Definition at line 570 of file mapping_q.cc.

## ◆ get_face_data() [2/2]

 virtual std::unique_ptr Mapping< dim, spacedim >::get_face_data ( const UpdateFlags update_flags, const Quadrature< dim - 1 > & quadrature ) const
protectedvirtualinherited
Deprecated:
Use the version taking a hp::QCollection argument.

## ◆ get_subface_data()

 std::unique_ptr< typename Mapping< dim, spacedim >::InternalDataBase > MappingQ< dim, spacedim >::get_subface_data ( const UpdateFlags update_flags, const Quadrature< dim - 1 > & quadrature ) const
overrideprotectedvirtualinherited

Like get_data() and get_face_data(), but in preparation for later calls to transform() or fill_fe_subface_values() that will need information about mappings from the reference face to a child of a face (i.e., subface) of a concrete cell.

Parameters
 update_flags A set of flags that define what is expected of the mapping class in future calls to transform() or the fill_fe_values() group of functions. This set of flags may contain flags that mappings do not know how to deal with (e.g., for information that is in fact computed by the finite element classes, such as UpdateFlags::update_values). Derived classes will need to store these flags, or at least that subset of flags that will require the mapping to perform any actions in fill_fe_values(), in InternalDataBase::update_each. quadrature The quadrature object for which mapping information will have to be computed. This includes the locations and weights of quadrature points.
Returns
A pointer to a newly created object of type InternalDataBase (or a derived class). Ownership of this object passes to the calling function.
Note
C++ allows that virtual functions in derived classes may return pointers to objects not of type InternalDataBase but in fact pointers to objects of classes derived from InternalDataBase. (This feature is called "covariant return types".) This is useful in some contexts where the calling is within the derived class and will immediately make use of the returned object, knowing its real (derived) type.

Implements Mapping< dim, spacedim >.

Definition at line 575 of file mapping_q.cc.

## ◆ fill_fe_values()

 CellSimilarity::Similarity MappingQ< dim, spacedim >::fill_fe_values ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const CellSimilarity::Similarity cell_similarity, const Quadrature< dim > & quadrature, const typename Mapping< dim, spacedim >::InternalDataBase & internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > & output_data ) const
overrideprotectedvirtualinherited

Compute information about the mapping from the reference cell to the real cell indicated by the first argument to this function. Derived classes will have to implement this function based on the kind of mapping they represent. It is called by FEValues::reinit().

Conceptually, this function's represents the application of the mapping $$\mathbf x=\mathbf F_K(\hat {\mathbf x})$$ from reference coordinates $$\mathbf\in [0,1]^d$$ to real space coordinates $$\mathbf x$$ for a given cell $$K$$. Its purpose is to compute the following kinds of data:

• Data that results from the application of the mapping itself, e.g., computing the location $$\mathbf x_q = \mathbf F_K(\hat{\mathbf x}_q)$$ of quadrature points on the real cell, and that is directly useful to users of FEValues, for example during assembly.
• Data that is necessary for finite element implementations to compute their shape functions on the real cell. To this end, the FEValues::reinit() function calls FiniteElement::fill_fe_values() after the current function, and the output of this function serves as input to FiniteElement::fill_fe_values(). Examples of information that needs to be computed here for use by the finite element classes is the Jacobian of the mapping, $$\hat\nabla \mathbf F_K(\hat{\mathbf x})$$ or its inverse, for example to transform the gradients of shape functions on the reference cell to the gradients of shape functions on the real cell.

The information computed by this function is used to fill the various member variables of the output argument of this function. Which of the member variables of that structure should be filled is determined by the update flags stored in the Mapping::InternalDataBase object passed to this function.

An extensive discussion of the interaction between this function and FEValues can be found in the How Mapping, FiniteElement, and FEValues work together documentation module.

Parameters
 [in] cell The cell of the triangulation for which this function is to compute a mapping from the reference cell to. [in] cell_similarity Whether or not the cell given as first argument is simply a translation, rotation, etc of the cell for which this function was called the most recent time. This information is computed simply by matching the vertices (as stored by the Triangulation) between the previous and the current cell. The value passed here may be modified by implementations of this function and should then be returned (see the discussion of the return value of this function). [in] quadrature A reference to the quadrature formula in use for the current evaluation. This quadrature object is the same as the one used when creating the internal_data object. The object is used both to map the location of quadrature points, as well as to compute the JxW values for each quadrature point (which involves the quadrature weights). [in] internal_data A reference to an object previously created by get_data() and that may be used to store information the mapping can compute once on the reference cell. See the documentation of the Mapping::InternalDataBase class for an extensive description of the purpose of these objects. [out] output_data A reference to an object whose member variables should be computed. Not all of the members of this argument need to be filled; which ones need to be filled is determined by the update flags stored inside the internal_data object.
Returns
An updated value of the cell_similarity argument to this function. The returned value will be used for the corresponding argument when FEValues::reinit() calls FiniteElement::fill_fe_values(). In most cases, derived classes will simply want to return the value passed for cell_similarity. However, implementations of this function may downgrade the level of cell similarity. This is, for example, the case for classes that take not only into account the locations of the vertices of a cell (as reported by the Triangulation), but also other information specific to the mapping. The purpose is that FEValues::reinit() can compute whether a cell is similar to the previous one only based on the cell's vertices, whereas the mapping may also consider displacement fields (e.g., in the MappingQ1Eulerian and MappingFEField classes). In such cases, the mapping may conclude that the previously computed cell similarity is too optimistic, and invalidate it for subsequent use in FiniteElement::fill_fe_values() by returning a less optimistic cell similarity value.
Note
FEValues ensures that this function is always called with the same pair of internal_data and output_data objects. In other words, if an implementation of this function knows that it has written a piece of data into the output argument in a previous call, then there is no need to copy it there again in a later call if the implementation knows that this is the same value.

Implements Mapping< dim, spacedim >.

Definition at line 580 of file mapping_q.cc.

## ◆ fill_fe_face_values() [1/2]

 void MappingQ< dim, spacedim >::fill_fe_face_values ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const unsigned int face_no, const hp::QCollection< dim - 1 > & quadrature, const typename Mapping< dim, spacedim >::InternalDataBase & internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > & output_data ) const
overrideprotectedvirtualinherited

This function is the equivalent to Mapping::fill_fe_values(), but for faces of cells. See there for an extensive discussion of its purpose. It is called by FEFaceValues::reinit().

Parameters
 [in] cell The cell of the triangulation for which this function is to compute a mapping from the reference cell to. [in] face_no The number of the face of the given cell for which information is requested. [in] quadrature A reference to the quadrature formula in use for the current evaluation. This quadrature object is the same as the one used when creating the internal_data object. The object is used both to map the location of quadrature points, as well as to compute the JxW values for each quadrature point (which involves the quadrature weights). [in] internal_data A reference to an object previously created by get_data() and that may be used to store information the mapping can compute once on the reference cell. See the documentation of the Mapping::InternalDataBase class for an extensive description of the purpose of these objects. [out] output_data A reference to an object whose member variables should be computed. Not all of the members of this argument need to be filled; which ones need to be filled is determined by the update flags stored inside the internal_data object.

Reimplemented from Mapping< dim, spacedim >.

Definition at line 592 of file mapping_q.cc.

## ◆ fill_fe_face_values() [2/2]

 virtual void Mapping< dim, spacedim >::fill_fe_face_values ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const unsigned int face_no, const Quadrature< dim - 1 > & quadrature, const typename Mapping< dim, spacedim >::InternalDataBase & internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > & output_data ) const
protectedvirtualinherited
Deprecated:
Use the version taking a hp::QCollection argument.

## ◆ fill_fe_subface_values()

 void MappingQ< dim, spacedim >::fill_fe_subface_values ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const unsigned int face_no, const unsigned int subface_no, const Quadrature< dim - 1 > & quadrature, const typename Mapping< dim, spacedim >::InternalDataBase & internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > & output_data ) const
overrideprotectedvirtualinherited

This function is the equivalent to Mapping::fill_fe_values(), but for subfaces (i.e., children of faces) of cells. See there for an extensive discussion of its purpose. It is called by FESubfaceValues::reinit().

Parameters
 [in] cell The cell of the triangulation for which this function is to compute a mapping from the reference cell to. [in] face_no The number of the face of the given cell for which information is requested. [in] subface_no The number of the child of a face of the given cell for which information is requested. [in] quadrature A reference to the quadrature formula in use for the current evaluation. This quadrature object is the same as the one used when creating the internal_data object. The object is used both to map the location of quadrature points, as well as to compute the JxW values for each quadrature point (which involves the quadrature weights). [in] internal_data A reference to an object previously created by get_data() and that may be used to store information the mapping can compute once on the reference cell. See the documentation of the Mapping::InternalDataBase class for an extensive description of the purpose of these objects. [out] output_data A reference to an object whose member variables should be computed. Not all of the members of this argument need to be filled; which ones need to be filled is determined by the update flags stored inside the internal_data object.

Implements Mapping< dim, spacedim >.

Definition at line 602 of file mapping_q.cc.

## ◆ fill_fe_immersed_surface_values()

 void MappingQ< dim, spacedim >::fill_fe_immersed_surface_values ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const NonMatching::ImmersedSurfaceQuadrature< dim > & quadrature, const typename Mapping< dim, spacedim >::InternalDataBase & internal_data, internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > & output_data ) const
overrideprotectedvirtualinherited

The equivalent of Mapping::fill_fe_values(), but for the case that the quadrature is an ImmersedSurfaceQuadrature. See there for a comprehensive description of the input parameters. This function is called by FEImmersedSurfaceValues::reinit().

Reimplemented from Mapping< dim, spacedim >.

Definition at line 613 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [1/7]

 Point< dim > MappingQ< dim, spacedim >::transform_real_to_unit_cell_internal ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const Point< spacedim > & p, const Point< dim > & initial_p_unit ) const
protectedinherited

Transform the point p on the real cell to the corresponding point on the unit cell cell by a Newton iteration.

Definition at line 740 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [2/7]

 Point< 1 > MappingQ< 1, 1 >::transform_real_to_unit_cell_internal ( const Triangulation< 1, 1 >::cell_iterator & cell, const Point< 1 > & p, const Point< 1 > & initial_p_unit ) const
protectedinherited

Definition at line 503 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [3/7]

 Point< 2 > MappingQ< 2, 2 >::transform_real_to_unit_cell_internal ( const Triangulation< 2, 2 >::cell_iterator & cell, const Point< 2 > & p, const Point< 2 > & initial_p_unit ) const
protectedinherited

Definition at line 523 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [4/7]

 Point< 3 > MappingQ< 3, 3 >::transform_real_to_unit_cell_internal ( const Triangulation< 3, 3 >::cell_iterator & cell, const Point< 3 > & p, const Point< 3 > & initial_p_unit ) const
protectedinherited

Definition at line 541 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [5/7]

 Point< 1 > MappingQ< 1, 2 >::transform_real_to_unit_cell_internal ( const Triangulation< 1, 2 >::cell_iterator & cell, const Point< 2 > & p, const Point< 1 > & initial_p_unit ) const
protectedinherited

Definition at line 559 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [6/7]

 Point< 2 > MappingQ< 2, 3 >::transform_real_to_unit_cell_internal ( const Triangulation< 2, 3 >::cell_iterator & cell, const Point< 3 > & p, const Point< 2 > & initial_p_unit ) const
protectedinherited

Definition at line 590 of file mapping_q.cc.

## ◆ transform_real_to_unit_cell_internal() [7/7]

 Point< 1 > MappingQ< 1, 3 >::transform_real_to_unit_cell_internal ( const Triangulation< 1, 3 >::cell_iterator & , const Point< 3 > & , const Point< 1 > & ) const
protectedinherited

Definition at line 619 of file mapping_q.cc.

 void MappingQ< dim, spacedim >::add_line_support_points ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, std::vector< Point< spacedim >> & a ) const
protectedvirtualinherited

Append the support points of all shape functions located on bounding lines of the given cell to the vector a. Points located on the vertices of a line are not included.

This function uses the underlying manifold object of the line (or, if none is set, of the cell) for the location of the requested points. This function is usually called by compute_mapping_support_points() function.

This function is made virtual in order to allow derived classes to choose shape function support points differently than the present class, which chooses the points as interpolation points on the boundary.

Definition at line 759 of file mapping_q.cc.

 void MappingQ< dim, spacedim >::add_quad_support_points ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, std::vector< Point< spacedim >> & a ) const
protectedvirtualinherited

Append the support points of all shape functions located on bounding faces (quads in 3d) of the given cell to the vector a. This function is only defined for dim=3. Points located on the vertices or lines of a quad are not included.

This function uses the underlying manifold object of the quad (or, if none is set, of the cell) for the location of the requested points. This function is usually called by compute_mapping_support_points().

This function is made virtual in order to allow derived classes to choose shape function support points differently than the present class, which chooses the points as interpolation points on the boundary.

Definition at line 778 of file mapping_q.cc.

 void MappingQ< 3, 3 >::add_quad_support_points ( const Triangulation< 3, 3 >::cell_iterator & cell, std::vector< Point< 3 >> & a ) const
protectedinherited

Definition at line 1704 of file mapping_q.cc.

 void MappingQ< 2, 3 >::add_quad_support_points ( const Triangulation< 2, 3 >::cell_iterator & cell, std::vector< Point< 3 >> & a ) const
protectedinherited

Definition at line 1773 of file mapping_q.cc.

## ◆ get_center()

 virtual Point Mapping< dim, spacedim >::get_center ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const bool map_center_of_reference_cell = true ) const
virtualinherited

Return the mapped center of a cell.

If you are using a (bi-,tri-)linear mapping that preserves vertex locations, this function simply returns the value also produced by cell->center(). However, there are also mappings that add displacements or choose completely different locations, e.g., MappingQEulerian, MappingQ1Eulerian, or MappingFEField, and mappings based on high order polynomials, for which the center may not coincide with the average of the vertex locations.

By default, this function returns the push forward of the center of the reference cell. If the parameter map_center_of_reference_cell is set to false, than the return value will be the average of the vertex locations, as returned by the get_vertices() method.

Parameters
 [in] cell The cell for which you want to compute the center [in] map_center_of_reference_cell A flag that switches the algorithm for the computation of the cell center from transform_unit_to_real_cell() applied to the center of the reference cell to computing the vertex averages.

## ◆ project_real_point_to_unit_point_on_face()

 Point Mapping< dim, spacedim >::project_real_point_to_unit_point_on_face ( const typename Triangulation< dim, spacedim >::cell_iterator & cell, const unsigned int face_no, const Point< spacedim > & p ) const
inherited

Transform the point p on the real cell to the corresponding point on the reference cell, and then project this point to a (dim-1)-dimensional point in the coordinate system of the face with the given face number face_no. Ideally the point p is near the face face_no, but any point in the cell can technically be projected.

This function does not make physical sense when dim=1, so it throws an exception in this case.

## ◆ ExcInvalidData()

 static ::ExceptionBase& Mapping< dim, spacedim >::ExcInvalidData ( )
staticinherited

Exception

## ◆ ExcTransformationFailed()

 static ::ExceptionBase& Mapping< dim, spacedim >::ExcTransformationFailed ( )
staticinherited

Computing the mapping between a real space point and a point in reference space failed, typically because the given point lies outside the cell where the inverse mapping is not unique.

Note
The message that will be printed by this exception reads:
"Computing the mapping between a real space point and a point in reference " "space failed, typically because the given point lies outside the cell " "where the inverse mapping is not unique."

## ◆ ExcDistortedMappedCell()

 static ::ExceptionBase& Mapping< dim, spacedim >::ExcDistortedMappedCell ( Point< spacedim > arg1, double arg2, int arg3 )
staticinherited

deal.II assumes the Jacobian determinant to be positive. When the cell geometry is distorted under the image of the mapping, the mapping becomes invalid and this exception is thrown.

Note
The message that will be printed by this exception reads:
<< "The image of the mapping applied to cell with center [" << arg1 << "] is distorted. The cell geometry or the " << "mapping are invalid, giving a non-positive volume " << "fraction of " << arg2 << " in quadrature point " << arg3 << '.'

## ◆ 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.

## ◆ support_point_cache

template<int dim, int spacedim = dim>
 std::shared_ptr > > > > MappingQCache< dim, spacedim >::support_point_cache
private

The point cache filled upon calling initialize(). It is made a shared pointer to allow several instances (created via clone()) to share this cache.

Definition at line 237 of file mapping_q_cache.h.

## ◆ clear_signal

template<int dim, int spacedim = dim>
 boost::signals2::connection MappingQCache< dim, spacedim >::clear_signal
private

The connection to Triangulation::signals::any that must be reset once this class goes out of scope.

Definition at line 243 of file mapping_q_cache.h.

## ◆ uses_level_info

template<int dim, int spacedim = dim>
 bool MappingQCache< dim, spacedim >::uses_level_info
private

Specifies if support_point_cache has been set up for the cells on the levels.

Definition at line 249 of file mapping_q_cache.h.

## ◆ polynomial_degree

 const unsigned int MappingQ< dim, spacedim >::polynomial_degree
protectedinherited

The degree of the polynomials used as shape functions for the mapping of cells.

Definition at line 628 of file mapping_q.h.

## ◆ line_support_points

 const std::vector > MappingQ< dim, spacedim >::line_support_points
protectedinherited

Definition at line 638 of file mapping_q.h.

## ◆ polynomials_1d

 const std::vector > MappingQ< dim, spacedim >::polynomials_1d
protectedinherited

Definition at line 645 of file mapping_q.h.

## ◆ renumber_lexicographic_to_hierarchic

 const std::vector MappingQ< dim, spacedim >::renumber_lexicographic_to_hierarchic
protectedinherited

Definition at line 652 of file mapping_q.h.

## ◆ unit_cell_support_points

 const std::vector > MappingQ< dim, spacedim >::unit_cell_support_points
protectedinherited

Definition at line 664 of file mapping_q.h.

## ◆ support_point_weights_perimeter_to_interior

 const std::vector > MappingQ< dim, spacedim >::support_point_weights_perimeter_to_interior
protectedinherited

A vector of tables of weights by which we multiply the locations of the support points on the perimeter of an object (line, quad, hex) to get the location of interior support points.

Access into this table is by [structdim-1], i.e., use 0 to access the support point weights on a line (i.e., the interior points of the GaussLobatto quadrature), use 1 to access the support point weights from to perimeter to the interior of a quad, and use 2 to access the support point weights from the perimeter to the interior of a hex.

The table itself contains as many columns as there are surrounding points to a particular object (2 for a line, 4 + 4*(degree-1) for a quad, 8 + 12*(degree-1) + 6*(degree-1)*(degree-1) for a hex) and as many rows as there are strictly interior points.

For the definition of this table see equation (8) of the ‘mapping’ report.

Definition at line 686 of file mapping_q.h.

## ◆ support_point_weights_cell

 const Table<2, double> MappingQ< dim, spacedim >::support_point_weights_cell
protectedinherited

A table of weights by which we multiply the locations of the vertex points of the cell to get the location of all additional support points, both on lines, quads, and hexes (as appropriate). This data structure is used when we fill all support points at once, which is the case if the same manifold is attached to all sub-entities of a cell. This way, we can avoid some of the overhead in transforming data for mappings.

The table has as many rows as there are vertices to the cell (2 in 1D, 4 in 2D, 8 in 3D), and as many rows as there are additional support points in the mapping, i.e., (degree+1)^dim - 2^dim.

Definition at line 700 of file mapping_q.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: