Sparse matrices

Detailed Description

Sparse matrix data structures.

Guanaqo supports the following (sparse) matrix formats:

• Dense: A plain dense matrix.
• SparseCSC: Compressed Sparse Column format.
• SparseCOO: Coordinate list format. Different index types are supported, and indices can be zero-based or one-based. For sparse formats, we also keep track of whether the indices are sorted or not.

The guanaqo::linalg::sparsity::Sparsity class is a type-erased wrapper around these various formats. Conversions between formats are supported by the guanaqo::linalg::sparsity::SparsityConverter<Sparsity,To> class (see Sparsity Conversions). The desired index options (zero/one-based, sorted/unsorted) can be specified using the guanaqo::linalg::sparsity::SparsityConversionRequest struct. While the conversions convert only the sparsity structure by default, they remember the original structure, and can be used to repeatedly convert the values as well. This is useful in optimization solvers, for example, where the sparsity structures of the Hessians and Jacobians are fixed, but the values change at each iteration.

Collaboration diagram for Sparse matrices:

Topics
	Sparsity Conversions
	Sparse matrix conversions.
	Sparsity Utilities
	Sparse matrix utilities for sorting indices, checking uniqueness, etc.

Files
file	sparsity.hpp
	Sparse and dense sparsity descriptors.

Classes
struct	guanaqo::linalg::sparsity::Dense
	Dense matrix structure. More...
struct	guanaqo::linalg::sparsity::SparseCSC< Index, StorageIndex >
	Sparse compressed-column structure (CCS or CSC). More...
struct	guanaqo::linalg::sparsity::SparseCOO< Index >
	Sparse coordinate list structure (COO). More...
struct	guanaqo::linalg::sparsity::Sparsity
	Stores any of the supported sparsity patterns. More...

Typedefs
using	guanaqo::linalg::sparsity::SparsityVariant
	Helper for Sparsity.

Enumerations
enum class	guanaqo::linalg::sparsity::Symmetry : uint8_t { guanaqo::linalg::sparsity::Symmetry::Unsymmetric = 0 , guanaqo::linalg::sparsity::Symmetry::Upper = 1 , guanaqo::linalg::sparsity::Symmetry::Lower = 2 }
	Describes the symmetry of matrices. More...

Functions
const char *	guanaqo::linalg::sparsity::enum_name (Symmetry s)
bool	guanaqo::linalg::sparsity::is_dense (const Sparsity &sp)
	Returns true if the sparsity pattern represents a dense matrix.
length_t	guanaqo::linalg::sparsity::get_nnz (const Sparsity &sp)
	Get the number of structurally nonzero elements.
Symmetry	guanaqo::linalg::sparsity::get_symmetry (const Sparsity &sp)
	Returns the symmetry of the sparsity pattern.
length_t	guanaqo::linalg::sparsity::num_rows (const Sparsity &sp)
	Returns the number of rows of the sparsity pattern.
length_t	guanaqo::linalg::sparsity::num_cols (const Sparsity &sp)
	Returns the number of rows of the sparsity pattern.

---

Class Documentation

guanaqo::linalg::sparsity::Dense

struct guanaqo::linalg::sparsity::Dense

Collaboration diagram for guanaqo::linalg::sparsity::Dense:

Class Members
length_t	rows = 0
length_t	cols = 0
Symmetry	symmetry = Symmetry::Unsymmetric

Typedef Documentation

SparsityVariant

using guanaqo::linalg::sparsity::SparsityVariant

#include <guanaqo/linalg/sparsity.hpp>

Initial value:

std::variant< 
   Dense,                            
   SparseCSC<int, int>,              
   SparseCSC<int, long>,             
   SparseCSC<int, long long>,        
   SparseCSC<long, long>,            
   SparseCSC<long, long long>,       
   SparseCSC<long long, long long>,  
   SparseCOO<int>,                   
   SparseCOO<long>,                  
   SparseCOO<long long>              
   >

Helper for Sparsity.

Definition at line 103 of file sparsity.hpp.

Enumeration Type Documentation

Symmetry

enum class guanaqo::linalg::sparsity::Symmetry : uint8_t

strong

#include <guanaqo/linalg/sparsity.hpp>

Describes the symmetry of matrices.

Enumerator
Unsymmetric	No symmetry.
Upper	Symmetric, upper-triangular part is stored.
Lower	Symmetric, lower-triangular part is stored.

Definition at line 20 of file sparsity.hpp.

Function Documentation

enum_name()

const char * guanaqo::linalg::sparsity::enum_name ( Symmetry s )

inline

#include <guanaqo/linalg/sparsity.hpp>

Definition at line 26 of file sparsity.hpp.

is_dense()

bool guanaqo::linalg::sparsity::is_dense ( const Sparsity & sp )

inline

#include <guanaqo/linalg/sparsity.hpp>

Returns true if the sparsity pattern represents a dense matrix.

Definition at line 139 of file sparsity.hpp.

get_nnz()

length_t guanaqo::linalg::sparsity::get_nnz ( const Sparsity & sp )

inline

#include <guanaqo/linalg/sparsity.hpp>

Get the number of structurally nonzero elements.

Definition at line 148 of file sparsity.hpp.

get_symmetry()

Symmetry guanaqo::linalg::sparsity::get_symmetry ( const Sparsity & sp )

inline

#include <guanaqo/linalg/sparsity.hpp>

Returns the symmetry of the sparsity pattern.

Definition at line 157 of file sparsity.hpp.

num_rows()

length_t guanaqo::linalg::sparsity::num_rows ( const Sparsity & sp )

inline

#include <guanaqo/linalg/sparsity.hpp>

Returns the number of rows of the sparsity pattern.

Definition at line 162 of file sparsity.hpp.

num_cols()

length_t guanaqo::linalg::sparsity::num_cols ( const Sparsity & sp )

inline

#include <guanaqo/linalg/sparsity.hpp>

Returns the number of rows of the sparsity pattern.

Definition at line 167 of file sparsity.hpp.