strumpack::HODLR Namespace Reference

Classes
class	HODLROptions
	Class containing several options for the HODLR code and data-structures. More...
struct	ExtractionMeta
class	HODLRMatrix
	Hierarchically low-rank matrix representation. More...
struct	AelemCommPtrs
class	ButterflyMatrix
	Butterfly matrix representation, this includes low-rank matrix representation as a special case. More...

Enumerations
enum class	CompressionAlgorithm { RANDOM_SAMPLING , ELEMENT_EXTRACTION }

Functions
template<typename real_t >
real_t	default_HODLR_rel_tol ()
template<typename real_t >
real_t	default_HODLR_abs_tol ()
template<>
float	default_HODLR_rel_tol ()
template<>
float	default_HODLR_abs_tol ()
std::string	get_name (CompressionAlgorithm a)
CompressionAlgorithm	get_compression_algorithm (const std::string &c)
template<typename scalar_t >
void	HODLR_block_evaluation (int *Ninter, int *Nallrows, int *Nallcols, int *Nalldat_loc, int *allrows, int *allcols, scalar_t *alldat_loc, int *rowids, int *colids, int *pgids, int *Npmap, int *pmaps, void *AC)
template<typename scalar_t >
void	HODLR_block_evaluation_seq (int *Ninter, int *Nallrows, int *Nallcols, int *Nalldat_loc, int *allrows, int *allcols, scalar_t *alldat_loc, int *rowids, int *colids, int *pgids, int *Npmap, int *pmaps, void *f)
template<typename integer_t >
DenseMatrix< int >	get_odiag_neighbors (int knn, const CSRGraph< integer_t > &gAB, const CSRGraph< integer_t > &gA, const CSRGraph< integer_t > &gB)

Detailed Description

Code in this namespace is a wrapper around Yang Liu's Fortran code: https://github.com/liuyangzhuan/ButterflyPACK

Code in this namespace is a wrapper aroung Yang Liu's Fortran code: https://github.com/liuyangzhuan/hod-lr-bf

Enumeration Type Documentation

CompressionAlgorithm

enum strumpack::HODLR::CompressionAlgorithm

strong

Enumeration of possible compressions, through randomized sampling or via element extraction.

Enumerator
RANDOM_SAMPLING	Random sampling.
ELEMENT_EXTRACTION	Element extraction.

Function Documentation

default_HODLR_abs_tol() [1/2]

template<typename real_t >

real_t strumpack::HODLR::default_HODLR_abs_tol ( )

inline

Get the default absolute HODLR compression tolerance (this is for double precision, might be overloaded for single precision). This can be changed using the HODLROptions object.

default_HODLR_abs_tol() [2/2]

template<>

float strumpack::HODLR::default_HODLR_abs_tol ( )

inline

Get the default absolute HODLR compression tolerance for single precision computations. This can be changed using the HODLROptions object.

default_HODLR_rel_tol() [1/2]

template<typename real_t >

real_t strumpack::HODLR::default_HODLR_rel_tol ( )

inline

Get the default relative HODLR compression tolerance (this is for double precision, might be overloaded depending on floating point precision). This can be changed using the HODLROptions object. Tuning this parameter (in the HODLROptions object) is crucial for performance of the HODLR algorithms.

default_HODLR_rel_tol() [2/2]

template<>

float strumpack::HODLR::default_HODLR_rel_tol ( )

inline

Get the default relative HODLR compression tolerance for single precision computations. This can be changed using the HODLROptions object. Tuning this parameter (in the HODLROptions<float> object) is crucial for performance of the HODLR algorithms.

get_compression_algorithm()

CompressionAlgorithm strumpack::HODLR::get_compression_algorithm

(

const std::string &

c

)

Return a CompressionAlgorithm enum based on the input string.

Parameters

c	String, possible values are 'natural', '2means', 'kdtree', 'pca' and 'cobble'. This is case sensitive.

get_name()

std::string strumpack::HODLR::get_name

(

CompressionAlgorithm

a

)

Return a string with the name of the compression algorithm.

Parameters

a	type of the compression algorihtm

Returns

name, string with a short description