Abstract interface of a local assembler for integral operators. More...

#include </home/wojtek/Projects/BEM/bempp-sven/bempp/lib/fiber/local_assembler_for_integral_operators.hpp>

Inheritance diagram for Fiber::LocalAssemblerForIntegralOperators< ResultType >:

Public Types
typedef ScalarTraits < ResultType >::RealType	CoordinateType

Public Member Functions
virtual void	evaluateLocalWeakForms (CallVariant callVariant, const std::vector< int > &elementIndicesA, int elementIndexB, LocalDofIndex localDofIndexB, std::vector< arma::Mat< ResultType > > &result, CoordinateType nominalDistance=-1.)=0
	Assemble local weak forms. More...

virtual void	evaluateLocalWeakForms (const std::vector< int > &testElementIndices, const std::vector< int > &trialElementIndices, Fiber::_2dArray< arma::Mat< ResultType > > &result, CoordinateType nominalDistance=-1.)=0
	Assemble local weak forms. More...

virtual CoordinateType	estimateRelativeScale (CoordinateType minDist) const =0
	Estimate how fast the entries in the matrix of this operator decay with interelement distance. More...

Detailed Description

template<typename ResultType>
class Fiber::LocalAssemblerForIntegralOperators< ResultType >

Abstract interface of a local assembler for integral operators.

Let $A$ be an integral boundary operator. A local assembler associated with this operator constructs matrices $A_{mn}$ , where $m$ is a test element number and $n$ a trial element number, with entries $(A_{mn})_{ij} = (u_{mi}, A v_{nj}$ ) where $(\cdot, \cdot)$ is the standard scalar product, $(u_{mi})_{i=1}^m$ are the element-level test functions defined on element $m$ and $(v_{nj})_{j=1}^n$ are the element-level trial functions defined on element $n$ .

The local assembler is responsible for choosing an appropriate way of evaluating the necessary integrals.

Member Function Documentation

template<typename ResultType>

virtual CoordinateType Fiber::LocalAssemblerForIntegralOperators< ResultType >::estimateRelativeScale ( CoordinateType minDist ) const

pure virtual

Estimate how fast the entries in the matrix of this operator decay with interelement distance.

This function should return a rough (!) estimate of the magnitude of the entries in the matrix of this operator associated with a pair of test and trial elements lying a distance minDist from each other, relative to the estimated magnitude of entries associated with coincident elements. If no good estimate can be given, the function can return 1.

Note: This function is called during ACA to detect block clusters on which the operator becomes very small and so can be safely approximated with 0.

Implemented in Fiber::DefaultLocalAssemblerForIntegralOperatorsOnSurfaces< BasisFunctionType, KernelType, ResultType, GeometryFactory >.

template<typename ResultType>

virtual void Fiber::LocalAssemblerForIntegralOperators< ResultType >::evaluateLocalWeakForms	(	CallVariant	callVariant,
		const std::vector< int > &	elementIndicesA,
		int	elementIndexB,
		LocalDofIndex	localDofIndexB,
		std::vector< arma::Mat< ResultType > > &	result,
		CoordinateType	nominalDistance = `-1.`
	)

pure virtual

Assemble local weak forms.

In this overload, a "column" of local weak forms is assembled. More specifically, on exit result is a vector of local weak forms corresponding to the following pairs of elements:

if callVariant is TEST_TRIAL, all pairs (elementA, elementB) for elementA in elementsA;
if callVariant is TRIAL_TEST, all pairs (elementB, elementA) for elementA in elementsA.

Unless localDofIndexB is set to ALL_DOFS, only entries corresponding to the (localDofIndexB)th local DOF on elementB are calculated.

If nominalDistance is nonnegative, it is taken as the distance between all element pairs for the purposes of selecting the quadrature method. Otherwise the interelement distance is calculated separately for each element pair.

Implemented in Fiber::DefaultLocalAssemblerForIntegralOperatorsOnSurfaces< BasisFunctionType, KernelType, ResultType, GeometryFactory >.

template<typename ResultType>

virtual void Fiber::LocalAssemblerForIntegralOperators< ResultType >::evaluateLocalWeakForms	(	const std::vector< int > &	testElementIndices,
		const std::vector< int > &	trialElementIndices,
		Fiber::_2dArray< arma::Mat< ResultType > > &	result,
		CoordinateType	nominalDistance = `-1.`
	)

pure virtual

Assemble local weak forms.

This overload constructs and assigns to the output parameter result the 2D array of local weak forms corresponding to all pairs (testElement, trialElement) with testElement in testElementIndices and trialElement in trialElementIndices.

This function should be used primarily for small blocks of elements lying close to each other.

If nominalDistance is nonnegative, it is taken as the distance between all element pairs for the purposes of selecting the quadrature method. Otherwise the interelement distance is calculated separately for each element pair.

Implemented in Fiber::DefaultLocalAssemblerForIntegralOperatorsOnSurfaces< BasisFunctionType, KernelType, ResultType, GeometryFactory >.

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

/home/wojtek/Projects/BEM/bempp-sven/bempp/lib/fiber/local_assembler_for_integral_operators.hpp

Public Types

Public Member Functions

Detailed Description

template<typename ResultType> class Fiber::LocalAssemblerForIntegralOperators< ResultType >

Member Function Documentation

template<typename ResultType>
class Fiber::LocalAssemblerForIntegralOperators< ResultType >