Dune::PDELab::ISTL::BCRSMatrixBackend< EntriesPerRow > Struct Template Reference

Backend using (possibly nested) ISTL BCRSMatrices. More...

#include <dune/pdelab/backend/istl/bcrsmatrixbackend.hh>

Public Types
typedef std::size_t	size_type
	The size type of the BCRSMatrix.
typedef PatternStatistics< size_type >	Statistics
	The type of the object holding the statistics generated during pattern construction.
template<typename Matrix , typename GFSV , typename GFSU >
using	Pattern = typename build_bcrs_pattern_type< typename Matrix::Container, GFSV, GFSU, typename GFSV::Ordering::ContainerAllocationTag >::type
	The type of the pattern object passed to the GridOperator for pattern construction.

Public Member Functions
template<typename GridOperator , typename Matrix >
std::vector< Statistics >	buildPattern (const GridOperator &grid_operator, Matrix &matrix) const
	Builds the matrix pattern associated with grid_operator and initializes matrix with it. More...
	BCRSMatrixBackend (const EntriesPerRow &entries_per_row)
	Constructs a BCRSMatrixBackend. More...

Detailed Description

template<typename EntriesPerRow = std::size_t>
struct Dune::PDELab::ISTL::BCRSMatrixBackend< EntriesPerRow >

Backend using (possibly nested) ISTL BCRSMatrices.

BCRSMatrixBackend is a matrix backend descriptor for ISTL matrices. It expects that both the ansatz and the test function space use ISTL vectors and automatically deduces the correct matrix type from those two vector backends.

The backend uses an accelerated pattern construction scheme, which requires the average number of non-zero entries per matrix row as a priori information. In constrast to the older construction scheme, the improved version never requires more memory than the matrix does after pattern construction and runs a lot faster, as long as it is provided with a reasonable estimate for the number of non-zero entries per row.

Examples

recipe-geometry-grid.cc, recipe-linear-system-assembly.cc, recipe-linear-system-solution-istl.cc, recipe-linear-system-solution-pdelab.cc, and recipe-operator-splitting.cc.

Constructor & Destructor Documentation

BCRSMatrixBackend()

template<typename EntriesPerRow = std::size_t>

Dune::PDELab::ISTL::BCRSMatrixBackend< EntriesPerRow >::BCRSMatrixBackend ( const EntriesPerRow &  entries_per_row )

inline

Constructs a BCRSMatrixBackend.

TODO: Document and flesh out the way this should work for nested matrices (use a nested array as entries_per_row).

Parameters

entries_per_row

The average number of nonzero entries per row in matrices created with this backend.

Member Function Documentation

buildPattern()

template<typename EntriesPerRow = std::size_t>

template<typename GridOperator , typename Matrix >

std::vector<Statistics> Dune::PDELab::ISTL::BCRSMatrixBackend< EntriesPerRow >::buildPattern ( const GridOperator &  grid_operator, Matrix &  matrix  ) const

inline

Builds the matrix pattern associated with grid_operator and initializes matrix with it.

Returns

a vector with statistics object for all leaf BCRSMatrices in row-major order.

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

• dune/pdelab/backend/istl/bcrsmatrixbackend.hh