MappingQ< dim, spacedim >::InternalData Class Reference

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

Detailed Description

template<int dim, int spacedim = dim>
class MappingQ< dim, spacedim >::InternalData

Storage for internal data of polynomial mappings. See Mapping::InternalDataBase for an extensive description.

For the current class, the InternalData class stores data that is computed once when the object is created (in get_data()) as well as data the class wants to store from between the call to fill_fe_values(), fill_fe_face_values(), or fill_fe_subface_values() until possible later calls from the finite element to functions such as transform(). The latter class of member variables are marked as 'mutable'.

Definition at line 293 of file mapping_q.h.

Inheritance diagram for MappingQ< dim, spacedim >::InternalData:

Public Types
using	VectorizedArrayType = VectorizedArray< double, std::min< std::size_t >(VectorizedArray< double >::size(),(dim<=2 ? 2 :4))>

Public Member Functions
	InternalData (const unsigned int polynomial_degree)
	InternalData (const std::shared_ptr< const FE_DGQ< 1, 1 > > &fe_dgq_1d)
virtual void	reinit (const UpdateFlags update_flags, const Quadrature< dim > &quadrature) override
void	initialize_face (const UpdateFlags update_flags, const Quadrature< dim > &quadrature, const unsigned int n_original_q_points)
virtual std::size_t	memory_consumption () const override

Public Attributes
std::vector< Point< dim > >	quadrature_points
std::array< std::vector< Tensor< 1, dim > >, GeometryInfo< dim >::faces_per_cell *(dim - 1)>	unit_tangentials
const unsigned int	polynomial_degree
const std::shared_ptr< const FE_DGQ< 1, 1 > >	fe_dgq_1d
const unsigned int	n_shape_functions
internal::MatrixFreeFunctions::ShapeInfo< double >	shape_info
AlignedVector< VectorizedArrayType >	scratch
bool	tensor_product_quadrature
std::vector< AlignedVector< Tensor< 1, spacedim > > >	aux
std::vector< Point< spacedim > >	mapping_support_points
AlignedVector< double >	volume_elements
internal::FEValuesImplementation::MappingRelatedData< dim, spacedim > *	output_data
UpdateFlags	update_each

Member Typedef Documentation

VectorizedArrayType

template<int dim, int spacedim = dim>

using MappingQ< dim, spacedim >::InternalData::VectorizedArrayType = VectorizedArray<double, std::min<std::size_t>(VectorizedArray<double>::size(), (dim <= 2 ? 2 : 4))>

For the fast tensor-product path of the MappingQ class, we choose SIMD vectors that are as wide as possible to minimize the number of arithmetic operations. However, we do not want to choose it wider than necessary, e.g., we avoid something like 8-wide AVX-512 when we only compute 3 components of a 3d computation. This is because the additional lanes would not do useful work, but a few operations on very wide vectors can already lead to a lower clock frequency of processors over long time spans (thousands of clock cycles). Hence, we choose 2-wide SIMD for 1D and 2d and 4-wide SIMD for 3d. Note that we do not immediately fall back to no SIMD for 1d because all architectures that support SIMD also support 128-bit vectors (and none is reported to reduce clock frequency for 128-bit SIMD).

Definition at line 391 of file mapping_q.h.

Constructor & Destructor Documentation

InternalData() [1/2]

template<int dim, int spacedim>

MappingQ< dim, spacedim >::InternalData::InternalData

(

const unsigned int

polynomial_degree

)

Constructor. The argument denotes the polynomial degree of the mapping to which this object will correspond.

Definition at line 48 of file mapping_q.cc.

InternalData() [2/2]

template<int dim, int spacedim>

MappingQ< dim, spacedim >::InternalData::InternalData

(

const std::shared_ptr< const FE_DGQ< 1, 1 > > &

fe_dgq_1d

)

Constructor. Re-uses an FE_DGQ (typically the same one owned by a MappingQ) which defines the one-dimensional polynomial space used by this mapping.

Definition at line 60 of file mapping_q.cc.

Member Function Documentation

reinit()

template<int dim, int spacedim>

void MappingQ< dim, spacedim >::InternalData::reinit ( const UpdateFlags  update_flags, const Quadrature< dim > &  quadrature  )

overridevirtual

Definition at line 91 of file mapping_q.cc.

initialize_face()

template<int dim, int spacedim>

void MappingQ< dim, spacedim >::InternalData::initialize_face	(	const UpdateFlags	update_flags,
		const Quadrature< dim > &	quadrature,
		const unsigned int	n_original_q_points
	)

Initialize the object's member variables related to cell and face data based on the given arguments. In order to initialize cell data, this function calls initialize().

Definition at line 168 of file mapping_q.cc.

memory_consumption()

template<int dim, int spacedim>

std::size_t MappingQ< dim, spacedim >::InternalData::memory_consumption ( ) const

overridevirtual

Return an estimate (in bytes) for the memory consumption of this object.

Definition at line 73 of file mapping_q.cc.

Member Data Documentation

quadrature_points

template<int dim, int spacedim = dim>

std::vector<Point<dim> > MappingQ< dim, spacedim >::InternalData::quadrature_points

Location of quadrature points of faces or subfaces in 3d with all possible orientations. Can be accessed with the correct offset provided via QProjector::DataSetDescriptor. Not needed/used for cells.

Definition at line 335 of file mapping_q.h.

unit_tangentials

template<int dim, int spacedim = dim>

std::array<std::vector<Tensor<1, dim> >, GeometryInfo<dim>::faces_per_cell *(dim - 1)> MappingQ< dim, spacedim >::InternalData::unit_tangentials

Unit tangential vectors. Used for the computation of boundary forms and normal vectors.

This array has (dim-1) * GeometryInfo::faces_per_cell entries. The first GeometryInfo::faces_per_cell contain the vectors in the first tangential direction for each face; the second set of GeometryInfo::faces_per_cell entries contain the vectors in the second tangential direction (only in 3d, since there we have 2 tangential directions per face), etc.

Filled once.

Definition at line 352 of file mapping_q.h.

polynomial_degree

template<int dim, int spacedim = dim>

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

The polynomial degree of the mapping. Since the objects here are also used (with minor adjustments) by MappingQ, we need to store this.

Definition at line 358 of file mapping_q.h.

fe_dgq_1d

template<int dim, int spacedim = dim>

const std::shared_ptr<const FE_DGQ<1, 1> > MappingQ< dim, spacedim >::InternalData::fe_dgq_1d

FiniteElement which defines the one-dimensional polynomial space used by the mapping.

Definition at line 364 of file mapping_q.h.

n_shape_functions

template<int dim, int spacedim = dim>

const unsigned int MappingQ< dim, spacedim >::InternalData::n_shape_functions

Number of shape functions. If this is a Q1 mapping, then it is simply the number of vertices per cell. However, since also derived classes use this class (e.g. the Mapping_Q() class), the number of shape functions may also be different.

In general, it is \((p+1)^\text{dim}\), where \(p\) is the polynomial degree of the mapping.

Definition at line 375 of file mapping_q.h.

shape_info

template<int dim, int spacedim = dim>

internal::MatrixFreeFunctions::ShapeInfo<double> MappingQ< dim, spacedim >::InternalData::shape_info

In case the quadrature rule given represents a tensor product we need to store the evaluations of the 1d polynomials at the 1d quadrature points. That is what this variable is for.

Definition at line 401 of file mapping_q.h.

scratch

template<int dim, int spacedim = dim>

AlignedVector<VectorizedArrayType> MappingQ< dim, spacedim >::InternalData::scratch

mutable

In case the quadrature rule given represents a tensor product we need to store temporary data in this object.

Definition at line 407 of file mapping_q.h.

tensor_product_quadrature

template<int dim, int spacedim = dim>

bool MappingQ< dim, spacedim >::InternalData::tensor_product_quadrature

Indicates whether the given Quadrature object is a tensor product.

Definition at line 412 of file mapping_q.h.

aux

template<int dim, int spacedim = dim>

std::vector<AlignedVector<Tensor<1, spacedim> > > MappingQ< dim, spacedim >::InternalData::aux

mutable

Auxiliary vectors for internal use.

Definition at line 417 of file mapping_q.h.

mapping_support_points

template<int dim, int spacedim = dim>

std::vector<Point<spacedim> > MappingQ< dim, spacedim >::InternalData::mapping_support_points

mutable

Stores the support points of the mapping shape functions.

Definition at line 422 of file mapping_q.h.

volume_elements

template<int dim, int spacedim = dim>

AlignedVector<double> MappingQ< dim, spacedim >::InternalData::volume_elements

mutable

The determinant of the Jacobian in each quadrature point. Filled if update_volume_elements.

Definition at line 428 of file mapping_q.h.

output_data

template<int dim, int spacedim = dim>

internal::FEValuesImplementation::MappingRelatedData<dim, spacedim>* MappingQ< dim, spacedim >::InternalData::output_data

mutable

Pointer to the mapping output data that holds most of the arrays, including the Jacobians representing the covariant and contravariant transformations.

Definition at line 436 of file mapping_q.h.

update_each

UpdateFlags Mapping< dim, spacedim >::InternalDataBase::update_each

inherited

A set of update flags specifying the kind of information that an implementation of the Mapping interface needs to compute on each cell or face, i.e., in Mapping::fill_fe_values() and friends.

This set of flags is stored here by implementations of Mapping::get_data(), Mapping::get_face_data(), or Mapping::get_subface_data(), and is that subset of the update flags passed to those functions that require re-computation on every cell. (The subset of the flags corresponding to information that can be computed once and for all already at the time of the call to Mapping::get_data() – or an implementation of that interface – need not be stored here because it has already been taken care of.)

Definition at line 703 of file mapping.h.

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

• include/deal.II/fe/mapping_q.h
• source/fe/mapping_q.cc