MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number > Class Template Reference

#include <deal.II/matrix_free/operators.h>

Public Member Functions
	CellwiseInverseMassMatrix (const FEEvaluationBase< dim, n_components, Number > &fe_eval)
void	apply (const AlignedVector< VectorizedArray< Number >> &inverse_coefficient, const unsigned int n_actual_components, const VectorizedArray< Number > *in_array, VectorizedArray< Number > *out_array) const
void	fill_inverse_JxW_values (AlignedVector< VectorizedArray< Number >> &inverse_jxw) const

Private Attributes
const FEEvaluationBase< dim, n_components, Number > &	fe_eval
AlignedVector< VectorizedArray< Number > >	inverse_shape

Detailed Description

template<int dim, int fe_degree, int n_components = 1, typename Number = double>
class MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number >

This class implements the operation of the action of the inverse of a mass matrix on an element for the special case of an evaluation object with as many quadrature points as there are cell degrees of freedom. It uses algorithms from FEEvaluation and produces the exact mass matrix for DGQ elements. This algorithm uses tensor products of inverse 1D shape matrices over quadrature points, so the inverse operation is exactly as expensive as applying the forward operator on each cell. Of course, for continuous finite elements this operation does not produce the inverse of a mass operation as the coupling between the elements cannot be considered by this operation.

The equation may contain variable coefficients, so the user is required to provide an array for the inverse of the local coefficient (this class provide a helper method 'fill_inverse_JxW_values' to get the inverse of a constant-coefficient operator).

Author

Martin Kronbichler, 2014

Definition at line 615 of file operators.h.

Constructor & Destructor Documentation

template<int dim, int fe_degree, int n_components, typename Number >

MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number >::CellwiseInverseMassMatrix ( const FEEvaluationBase< dim, n_components, Number > &  fe_eval )

inline

Constructor. Initializes the shape information from the ShapeInfo field in the class FEEval.

Definition at line 879 of file operators.h.

Member Function Documentation

template<int dim, int fe_degree, int n_components, typename Number >

void MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number >::apply ( const AlignedVector< VectorizedArray< Number >> &  inverse_coefficient, const unsigned int  n_actual_components, const VectorizedArray< Number > *  in_array, VectorizedArray< Number > *  out_array  ) const

inline

Applies the inverse mass matrix operation on an input array. It is assumed that the passed input and output arrays are of correct size, namely FEEval::dofs_per_cell * n_components long. The inverse of the local coefficient (also containing the inverse JxW values) must be passed as first argument. Passing more than one component in the coefficient is allowed.

Definition at line 936 of file operators.h.

template<int dim, int fe_degree, int n_components, typename Number >

void MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number >::fill_inverse_JxW_values ( AlignedVector< VectorizedArray< Number >> &  inverse_jxw ) const

inline

Fills the given array with the inverse of the JxW values, i.e., a mass matrix with coefficient 1. Non-unit coefficients must be multiplied (in inverse form) to this array.

Definition at line 908 of file operators.h.

Member Data Documentation

template<int dim, int fe_degree, int n_components = 1, typename Number = double>

const FEEvaluationBase<dim, n_components, Number>& MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number >::fe_eval

private

A reference to the FEEvaluation object for getting the JxW_values.

Definition at line 652 of file operators.h.

template<int dim, int fe_degree, int n_components = 1, typename Number = double>

AlignedVector<VectorizedArray<Number> > MatrixFreeOperators::CellwiseInverseMassMatrix< dim, fe_degree, n_components, Number >::inverse_shape

private

A structure to hold inverse shape functions

Definition at line 657 of file operators.h.

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

• deal.II/matrix_free/operators.h