Class PETScLevelSolver is an abstract LinearSolver for solving systems of linear equations on a single SAMRAI::hier::PatchLevel using PETSc. More...

#include </home/runner/work/IBAMR/IBAMR/ibtk/include/ibtk/PETScLevelSolver.h>

Inheritance diagram for IBTK::PETScLevelSolver:

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Public Member Functions
	PETScLevelSolver ()
	Default constructor.

	~PETScLevelSolver ()
	Destructor.

void	setKSPType (const std::string &ksp_type)
	Set the KSP type.

void	setOptionsPrefix (const std::string &options_prefix)
	Set the options prefix used by this PETSc solver object.

const KSP &	getPETScKSP () const
	Get the PETSc KSP object.

void	getASMSubdomains (std::vector< IS > nonoverlapping_subdomains, std::vector< IS > overlapping_subdomains)
	Get ASM subdomains.

Public Member Functions inherited from IBTK::LinearSolver
	LinearSolver ()
	Constructor.

virtual	~LinearSolver ()
	Empty virtual destructor.

virtual bool	getNullspaceContainsConstantVector () const
	Get whether the nullspace of the linear system contains th constant vector.

virtual const std::vector< SAMRAI::tbox::Pointer< SAMRAI::solv::SAMRAIVectorReal< NDIM, double > > > &	getNullspaceBasisVectors () const
	Get the basis vectors for the nullspace of the linear system.

virtual void	setInitialGuessNonzero (bool initial_guess_nonzero=true)
	Set whether the initial guess is non-zero.

virtual bool	getInitialGuessNonzero () const
	Get whether the initial guess is non-zero.

virtual void	printClassData (std::ostream &stream) override
	Print class data to stream.

Public Member Functions inherited from IBTK::GeneralSolver
	GeneralSolver ()=default
	Constructor.

virtual	~GeneralSolver ()=default
	Empty virtual destructor.

const std::string &	getName () const
	Return the object name.

virtual bool	getIsInitialized () const
	Return whether the operator is initialized.

virtual void	setHomogeneousBc (bool homogeneous_bc)
	Set whether the solver should use homogeneous boundary conditions.

virtual bool	getHomogeneousBc () const
	Return whether the solver is using homogeneous boundary conditions.

virtual void	setSolutionTime (double solution_time)
	Set the time at which the solution is to be evaluated.

virtual double	getSolutionTime () const
	Get the time at which the solution is being evaluated.

virtual void	setTimeInterval (double current_time, double new_time)
	Set the current time interval.

virtual std::pair< double, double >	getTimeInterval () const
	Get the current time interval.

virtual double	getDt () const
	Get the current time step size.

virtual void	setHierarchyMathOps (SAMRAI::tbox::Pointer< HierarchyMathOps > hier_math_ops)
	Set the HierarchyMathOps object used by the solver.

virtual SAMRAI::tbox::Pointer< HierarchyMathOps >	getHierarchyMathOps () const
	Get the HierarchyMathOps object used by the solver.

virtual void	setMaxIterations (int max_iterations)
	Set the maximum number of nonlinear iterations to use per solve.

virtual int	getMaxIterations () const
	Get the maximum number of nonlinear iterations to use per solve.

virtual void	setAbsoluteTolerance (double abs_residual_tol)
	Set the absolute residual tolerance for convergence.

virtual double	getAbsoluteTolerance () const
	Get the absolute residual tolerance for convergence.

virtual void	setRelativeTolerance (double rel_residual_tol)
	Set the relative residual tolerance for convergence.

virtual double	getRelativeTolerance () const
	Get the relative residual tolerance for convergence.

virtual int	getNumIterations () const
	Return the iteration count from the most recent solve.

virtual double	getResidualNorm () const
	Return the residual norm from the most recent iteration.

virtual void	setLoggingEnabled (bool enable_logging=true)
	Enable or disable logging.

virtual bool	getLoggingEnabled () const
	Determine whether logging is enabled or disabled.

Protected Attributes
PETSc objects.
std::string	d_ksp_type = KSPGMRES

std::string	d_pc_type = PCILU

std::string	d_shell_pc_type

std::string	d_options_prefix

KSP	d_petsc_ksp = nullptr

Mat	d_petsc_mat = nullptr

Mat	d_petsc_pc = nullptr

MatNullSpace	d_petsc_nullsp

Vec	d_petsc_x = nullptr

Vec	d_petsc_b = nullptr

Support for additive and multiplicative Schwarz preconditioners.
Vec	d_local_x

Vec	d_local_y

SAMRAI::hier::IntVector< NDIM >	d_box_size

SAMRAI::hier::IntVector< NDIM >	d_overlap_size

int	d_n_local_subdomains

int	d_n_subdomains_max

std::vector< IS >	d_overlap_is

std::vector< IS >	d_nonoverlap_is

std::vector< IS >	d_local_overlap_is

std::vector< IS >	d_local_nonoverlap_is

std::vector< VecScatter >	d_restriction

std::vector< VecScatter >	d_prolongation

std::vector< KSP >	d_sub_ksp

Mat *	d_sub_mat

Mat *	d_sub_bc_mat

std::vector< Vec >	d_sub_x

std::vector< Vec >	d_sub_y

Protected Attributes inherited from IBTK::LinearSolver
bool	d_initial_guess_nonzero = true

bool	d_nullspace_contains_constant_vec = false

std::vector< SAMRAI::tbox::Pointer< SAMRAI::solv::SAMRAIVectorReal< NDIM, double > > >	d_nullspace_basis_vecs

Protected Attributes inherited from IBTK::GeneralSolver
std::string	d_object_name = "unitialized"

bool	d_is_initialized = false

bool	d_homogeneous_bc = false

double	d_solution_time = std::numeric_limits<double>::quiet_NaN()

double	d_current_time = std::numeric_limits<double>::quiet_NaN()

double	d_new_time = std::numeric_limits<double>::quiet_NaN()

double	d_rel_residual_tol = 0.0

double	d_abs_residual_tol = 0.0

int	d_max_iterations = 100

int	d_current_iterations = 0

double	d_current_residual_norm = std::numeric_limits<double>::quiet_NaN()

SAMRAI::tbox::Pointer< HierarchyMathOps >	d_hier_math_ops

bool	d_hier_math_ops_external = false

bool	d_enable_logging = false

Linear solver functionality.
SAMRAI::tbox::Pointer< SAMRAI::hier::PatchHierarchy< NDIM > >	d_hierarchy
	Associated hierarchy.

int	d_level_num = IBTK::invalid_level_number
	Associated patch level and C-F boundary (for level numbers > 0).

SAMRAI::tbox::Pointer< SAMRAI::hier::PatchLevel< NDIM > >	d_level

SAMRAI::tbox::Pointer< SAMRAI::hier::CoarseFineBoundary< NDIM > >	d_cf_boundary

SAMRAIDataCache	d_cached_eulerian_data
	Scratch data.

void	setNullspace (bool contains_constant_vec, const std::vector< SAMRAI::tbox::Pointer< SAMRAI::solv::SAMRAIVectorReal< NDIM, double > > > &nullspace_basis_vecs=std::vector< SAMRAI::tbox::Pointer< SAMRAI::solv::SAMRAIVectorReal< NDIM, double > > >()) override
	Set the nullspace of the linear system.

bool	solveSystem (SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &x, SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &b) override
	Solve the linear system of equations for . More...

void	initializeSolverState (const SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &x, const SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &b) override
	Compute hierarchy dependent data required for solving . More...

void	deallocateSolverState () override
	Remove all hierarchy dependent data allocated by initializeSolverState(). More...

void	init (SAMRAI::tbox::Pointer< SAMRAI::tbox::Database > input_db, const std::string &default_options_prefix)
	Basic initialization.

virtual void	generateASMSubdomains (std::vector< std::set< int > > &overlap_is, std::vector< std::set< int > > &nonoverlap_is)
	Generate IS/subdomains for Schwartz type preconditioners.

virtual void	generateFieldSplitSubdomains (std::vector< std::string > &field_names, std::vector< std::set< int > > &field_is)
	Generate IS/subdomains for fieldsplit type preconditioners.

virtual void	initializeSolverStateSpecialized (const SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &x, const SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &b)=0
	Compute hierarchy dependent data required for solving .

virtual void	deallocateSolverStateSpecialized ()=0
	Remove all hierarchy dependent data allocated by initializeSolverStateSpecialized().

virtual void	copyToPETScVec (Vec &petsc_x, SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &x)=0
	Copy a generic vector to the PETSc representation.

virtual void	copyFromPETScVec (Vec &petsc_x, SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &x)=0
	Copy a generic vector from the PETSc representation.

virtual void	setupKSPVecs (Vec &petsc_x, Vec &petsc_b, SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &x, SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &b)=0
	Copy solution and right-hand-side data to the PETSc representation, including any modifications to account for boundary conditions.

virtual void	setupNullspace ()
	Setup the solver nullspace (if any).

Field split preconditioner.
std::vector< std::string >	d_field_name

std::vector< IS >	d_field_is

Additional Inherited Members
Protected Member Functions inherited from IBTK::GeneralSolver
void	init (const std::string &object_name, bool homogeneous_bc)

virtual void	initSpecialized (const std::string &object_name, bool homogeneous_bc)

Detailed Description

Class PETScLevelSolver is an abstract LinearSolver for solving systems of linear equations on a single SAMRAI::hier::PatchLevel using PETSc.

Sample parameters for initialization from database (and their default values):

options_prefix = ""           // see setOptionsPrefix()
ksp_type = "gmres"            // see setKSPType()
initial_guess_nonzero = TRUE  // see setInitialGuessNonzero()
rel_residual_tol = 1.0e-5     // see setRelativeTolerance()
abs_residual_tol = 1.0e-50    // see setAbsoluteTolerance()
max_iterations = 10000        // see setMaxIterations()
enable_logging = FALSE        // see setLoggingEnabled()

PETSc is developed at the Argonne National Laboratory Mathematics and Computer Science Division. For more information about PETSc, see http://www.mcs.anl.gov/petsc.

Member Function Documentation

◆ deallocateSolverState()

void IBTK::PETScLevelSolver::deallocateSolverState ( )

overridevirtual

Remove all hierarchy dependent data allocated by initializeSolverState().

Note: It is safe to call deallocateSolverState() when the solver state is already deallocated.; Subclasses of class PETScLevelSolver should not override this method. Instead, they should override the protected method deallocatedSolverStateSpecialized().

See also: initializeSolverState

Reimplemented from IBTK::GeneralSolver.

◆ initializeSolverState()

void IBTK::PETScLevelSolver::initializeSolverState	(	const SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &	x,
		const SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &	b
	)

overridevirtual

Compute hierarchy dependent data required for solving $Ax=b$ .

By default, the solveSystem() method computes some required hierarchy dependent data before solving and removes that data after the solve. For multiple solves that use the same hierarchy configuration, it is more efficient to:

initialize the hierarchy-dependent data required by the solver via initializeSolverState(),
solve the system one or more times via solveSystem(), and
remove the hierarchy-dependent data via deallocateSolverState().

Note that it is generally necessary to reinitialize the solver state when the hierarchy configuration changes.

Parameters

x	solution vector
b	right-hand-side vector

Conditions on Parameters:

vectors x and b must have same patch hierarchy
vectors x and b must have same structure, depth, etc.

Note: The vector arguments for solveSystem() need not match those for initializeSolverState(). However, there must be a certain degree of similarity, including:

hierarchy configuration (hierarchy pointer and range of levels)
number, type and alignment of vector component data
ghost cell widths of data in the solution x and right-hand-side b vectors

Note: It is safe to call initializeSolverState() when the state is already initialized. In this case, the solver state is first deallocated and then reinitialized.; Subclasses of class PETScLevelSolver should not override this method. Instead, they should override the protected method initializeSolverStateSpecialized().

See also: deallocateSolverState

Reimplemented from IBTK::GeneralSolver.

◆ solveSystem()

bool IBTK::PETScLevelSolver::solveSystem	(	SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &	x,
		SAMRAI::solv::SAMRAIVectorReal< NDIM, double > &	b
	)

overridevirtual

Solve the linear system of equations $Ax=b$ for $x$ .

Before calling solveSystem(), the form of the solution x and right-hand-side b vectors must be set properly by the user on all patch interiors on the specified range of levels in the patch hierarchy. The user is responsible for all data management for the quantities associated with the solution and right-hand-side vectors. In particular, patch data in these vectors must be allocated prior to calling this method.

Parameters

x	solution vector
b	right-hand-side vector

Conditions on Parameters:

vectors x and b must have same patch hierarchy
vectors x and b must have same structure, depth, etc.

Note: The vector arguments for solveSystem() need not match those for initializeSolverState(). However, there must be a certain degree of similarity, including:

hierarchy configuration (hierarchy pointer and range of levels)
number, type and alignment of vector component data
ghost cell widths of data in the solution x and right-hand-side b vectors

Note: The solver need not be initialized prior to calling solveSystem(); however, see initializeSolverState() and deallocateSolverState() for opportunities to save overhead when performing multiple consecutive solves.

See also: initializeSolverState; deallocateSolverState

Returns: true if the solver converged to the specified tolerances, false otherwise

Implements IBTK::GeneralSolver.

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

/home/runner/work/IBAMR/IBAMR/ibtk/include/ibtk/PETScLevelSolver.h
/home/runner/work/IBAMR/IBAMR/ibtk/src/solvers/impls/PETScLevelSolver.cpp

Public Member Functions

Protected Attributes

Linear solver functionality.

Field split preconditioner.

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ deallocateSolverState()

◆ initializeSolverState()

◆ solveSystem()