basic solver for Ax = b More...

#include <linear_solver.h>

Inheritance diagram for g2o::LinearSolver< MatrixType >:

[legend]

Public Member Functions
	LinearSolver ()

virtual	~LinearSolver ()

virtual bool	init ()=0

virtual bool	solve (const SparseBlockMatrix< MatrixType > &A, double x, double b)=0

virtual bool	solveBlocks (double **&blocks, const SparseBlockMatrix< MatrixType > &A)

virtual bool	solvePattern (SparseBlockMatrix< MatrixX > &spinv, const std::vector< std::pair< int, int > > &blockIndices, const SparseBlockMatrix< MatrixType > &A)

bool	writeDebug () const
	write a debug dump of the system matrix if it is not PSD in solve

void	setWriteDebug (bool b)

Static Public Member Functions
static void	allocateBlocks (const SparseBlockMatrix< MatrixType > &A, double **&blocks)
	allocate block memory structure

static void	deallocateBlocks (const SparseBlockMatrix< MatrixType > &A, double **&blocks)
	de-allocate the block structure

template<typename BlockDerived , typename ScalarDerived >
static void	blockToScalarPermutation (const SparseBlockMatrix< MatrixType > &A, const Eigen::MatrixBase< BlockDerived > &p, const Eigen::MatrixBase< ScalarDerived > &scalar)

Protected Attributes
bool	_writeDebug

Detailed Description

template<typename MatrixType>
class g2o::LinearSolver< MatrixType >

basic solver for Ax = b

basic solver for Ax = b which has to reimplemented for different linear algebra libraries. A is assumed to be symmetric (only upper triangular block is stored) and positive-semi-definite.

Definition at line 47 of file linear_solver.h.

Constructor & Destructor Documentation

◆ LinearSolver()

template<typename MatrixType >

g2o::LinearSolver< MatrixType >::LinearSolver ( )

inline

Definition at line 49 of file linear_solver.h.

49: _writeDebug(true){};

g2o::LinearSolver::_writeDebug

bool _writeDebug

Definition linear_solver.h:143

◆ ~LinearSolver()

template<typename MatrixType >

virtual g2o::LinearSolver< MatrixType >::~LinearSolver ( )

inlinevirtual

Definition at line 50 of file linear_solver.h.

50{}

Member Function Documentation

◆ allocateBlocks()

template<typename MatrixType >

static void g2o::LinearSolver< MatrixType >::allocateBlocks	(	const SparseBlockMatrix< MatrixType > &	A,
		double **&	blocks
	)

inlinestatic

allocate block memory structure

Definition at line 97 of file linear_solver.h.

                                               {
    blocks = new double*[A.rows()];
    double** block = blocks;
    for (size_t i = 0; i < A.rowBlockIndices().size(); ++i) {
      int dim = A.rowsOfBlock(i) * A.colsOfBlock(i);
      *block = new double[dim];
      block++;
    }
  }

References g2o::SparseBlockMatrix< MatrixType >::colsOfBlock(), g2o::SparseBlockMatrix< MatrixType >::rowBlockIndices(), g2o::SparseBlockMatrix< MatrixType >::rows(), and g2o::SparseBlockMatrix< MatrixType >::rowsOfBlock().

Referenced by g2o::LinearSolverCCS< MatrixType >::solveBlocks().

◆ blockToScalarPermutation()

template<typename MatrixType >

template<typename BlockDerived , typename ScalarDerived >

static void g2o::LinearSolver< MatrixType >::blockToScalarPermutation	(	const SparseBlockMatrix< MatrixType > &	A,
		const Eigen::MatrixBase< BlockDerived > &	p,
		const Eigen::MatrixBase< ScalarDerived > &	scalar
	)

inlinestatic

Convert a block permutation matrix to a scalar permutation

Definition at line 122 of file linear_solver.h.

                                                      {
    int n = A.cols();
    Eigen::MatrixBase<ScalarDerived>& scalarPermutation =
        const_cast<Eigen::MatrixBase<ScalarDerived>&>(scalar);
    if (scalarPermutation.size() == 0) scalarPermutation.derived().resize(n);
    if (scalarPermutation.size() < n) scalarPermutation.derived().resize(2 * n);
    size_t scalarIdx = 0;
    for (size_t i = 0; i < A.colBlockIndices().size(); ++i) {
      int base = A.colBaseOfBlock(p(i));
      int nCols = A.colsOfBlock(p(i));
      for (int j = 0; j < nCols; ++j) {
        scalarPermutation(scalarIdx++) = base++;
      }
    }
    assert((int)scalarIdx == n);
  }

References g2o::SparseBlockMatrix< MatrixType >::colBaseOfBlock(), g2o::SparseBlockMatrix< MatrixType >::colBlockIndices(), g2o::SparseBlockMatrix< MatrixType >::cols(), and g2o::SparseBlockMatrix< MatrixType >::colsOfBlock().

Referenced by g2o::LinearSolverCholmod< MatrixType >::computeSymbolicDecomposition(), g2o::LinearSolverCSparse< MatrixType >::computeSymbolicDecomposition(), and g2o::LinearSolverEigen< MatrixType >::computeSymbolicDecomposition().

◆ deallocateBlocks()

template<typename MatrixType >

static void g2o::LinearSolver< MatrixType >::deallocateBlocks	(	const SparseBlockMatrix< MatrixType > &	A,
		double **&	blocks
	)

inlinestatic

de-allocate the block structure

Definition at line 109 of file linear_solver.h.

                                                 {
    for (size_t i = 0; i < A.rowBlockIndices().size(); ++i) {
      delete[] blocks[i];
    }
    delete[] blocks;
    blocks = nullptr;
  }

References g2o::SparseBlockMatrix< MatrixType >::rowBlockIndices().

◆ init()

template<typename MatrixType >

virtual bool g2o::LinearSolver< MatrixType >::init ( )

pure virtual

init for operating on matrices with a different non-zero pattern like before

Implemented in g2o::LinearSolverCholmodOnline< MatrixType >, g2o::LinearSolverCholmod< MatrixType >, g2o::LinearSolverCSparse< MatrixType >, g2o::LinearSolverDense< MatrixType >, g2o::LinearSolverEigen< MatrixType >, and g2o::LinearSolverPCG< MatrixType >.

◆ setWriteDebug()

template<typename MatrixType >

void g2o::LinearSolver< MatrixType >::setWriteDebug ( bool b )

inline

Definition at line 94 of file linear_solver.h.

94{ _writeDebug = b; }

References g2o::LinearSolver< MatrixType >::_writeDebug.

◆ solve()

template<typename MatrixType >

virtual bool g2o::LinearSolver< MatrixType >::solve	(	const SparseBlockMatrix< MatrixType > &	A,
		double *	x,
		double *	b
	)

pure virtual

Assumes that A is the same matrix for several calls. Among other assumptions, the non-zero pattern does not change! If the matrix changes call init() before. solve system Ax = b, x and b have to allocated beforehand!!

Implemented in g2o::LinearSolverCholmodOnline< MatrixType >, g2o::LinearSolverCholmod< MatrixType >, g2o::LinearSolverCSparse< MatrixType >, g2o::LinearSolverDense< MatrixType >, g2o::LinearSolverEigen< MatrixType >, and g2o::LinearSolverPCG< MatrixType >.

◆ solveBlocks()

template<typename MatrixType >

virtual bool g2o::LinearSolver< MatrixType >::solveBlocks	(	double **&	blocks,
		const SparseBlockMatrix< MatrixType > &	A
	)

inlinevirtual

Inverts the diagonal blocks of A

Returns: false if not defined.

Reimplemented in g2o::LinearSolverCCS< MatrixType >.

Definition at line 71 of file linear_solver.h.

                                                                   {
    (void)blocks;
    (void)A;
    return false;
  }

◆ solvePattern()

template<typename MatrixType >

virtual bool g2o::LinearSolver< MatrixType >::solvePattern	(	SparseBlockMatrix< MatrixX > &	spinv,
		const std::vector< std::pair< int, int > > &	blockIndices,
		const SparseBlockMatrix< MatrixType > &	A
	)

inlinevirtual

Inverts the a block pattern of A in spinv

Returns: false if not defined.

Reimplemented in g2o::LinearSolverCCS< MatrixType >.

Definition at line 82 of file linear_solver.h.

                                              {
    (void)spinv;
    (void)blockIndices;
    (void)A;
    return false;
  }

◆ writeDebug()

template<typename MatrixType >

bool g2o::LinearSolver< MatrixType >::writeDebug ( ) const

inline

write a debug dump of the system matrix if it is not PSD in solve

Definition at line 93 of file linear_solver.h.

93{ return _writeDebug; }

References g2o::LinearSolver< MatrixType >::_writeDebug.

Referenced by g2o::LinearSolverEigen< MatrixType >::computeCholesky(), g2o::LinearSolverCholmod< MatrixType >::computeCholmodFactor(), and g2o::LinearSolverCSparse< MatrixType >::solve().

Member Data Documentation

◆ _writeDebug

template<typename MatrixType >

bool g2o::LinearSolver< MatrixType >::_writeDebug

protected

Definition at line 143 of file linear_solver.h.

Referenced by g2o::LinearSolver< MatrixType >::setWriteDebug(), and g2o::LinearSolver< MatrixType >::writeDebug().

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

/build/reproducible-path/g2o-0~20230806/g2o/core/linear_solver.h

Public Member Functions

Static Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ LinearSolver()

◆ ~LinearSolver()

Member Function Documentation

◆ allocateBlocks()

◆ blockToScalarPermutation()

◆ deallocateBlocks()

◆ init()

◆ setWriteDebug()

◆ solve()

◆ solveBlocks()

◆ solvePattern()

◆ writeDebug()

Member Data Documentation

◆ _writeDebug