Implements coarsening, e.g. agglomeration of blocked matrices into dense or low-rank matrices if the later use less memory.

#include <TCoarsen.hh>

Public Member Functions
	TCoarsen (const bool aallow_dense=true, const bool arecompress_lr=false, const size_t amax_block_size=50, const size_t amax_dense_size=500)
	constructs coarsening object

virtual	~TCoarsen ()
	destructor

TCoarsen &	allow_dense (const bool b)
	set dense conversion mode, e.g. low-rank to dense or block to dense

TCoarsen &	recompress_lr (const bool b)
	set recompression of low-rank blocks

TCoarsen &	only_offdiag_lr (const bool b)
	turn on/off low-rank compression of diagonal blocks

TCoarsen &	max_block_size (const size_t n)
	set maximal size of block-matrices, still worth to try coarsening

TCoarsen &	max_dense_size (const size_t n)
	set maximal size of dense matrices, still worth to try coarsening

template<typename value_t >
TMatrix< value_t > *	rec_coarsen (TMatrix< value_t > *A, const TTruncAcc &acc) const

template<typename value_t >
TMatrix< value_t > *	coarsen (TMatrix< value_t > *A, const TTruncAcc &acc) const

Protected Member Functions
template<typename value_t >
size_t	byte_size (const TMatrix< value_t > *A) const
	return "corrected" bytesizes, e.g. in symmetric case, of matrices for internal use

Member Function Documentation

◆ coarsen()

coarsen matrix A without recursion, i.e. no coarsening of subblocks.

Parameters

A	matrix to coarsen
acc	accuracy to maintain during coarsening

coarsen matrix A with recursion, i.e. first try to coarsen subblocks.

Parameters

A	matrix to coarsen
acc	accuracy to maintain during coarsening