This class implements Newton-Raphson Method, derived from abstract NumericalMethod class for solving non-linear problems. More...

#include <nrsolver.h>

Inheritance diagram for oofem::NRSolver:

Collaboration diagram for oofem::NRSolver:

Public Member Functions
	NRSolver (Domain d, EngngModel m)

virtual	~NRSolver ()

virtual NM_Status	solve (SparseMtrx &k, FloatArray &R, FloatArray R0, FloatArray &X, FloatArray &dX, FloatArray &F, const FloatArray &internalForcesEBENorm, double &l, referenceLoadInputModeType rlm, int &nite, TimeStep )
	Solves the given sparse linear system of equations . More...

virtual void	printState (FILE *outputStream)
	Prints status message of receiver to output stream. More...

virtual IRResultType	initializeFrom (InputRecord *ir)

virtual const char *	giveClassName () const

virtual const char *	giveInputRecordName () const

virtual void	setDomain (Domain *d)

virtual void	reinitialize ()
	Reinitializes the receiver. More...

virtual SparseLinearSystemNM *	giveLinearSolver ()
	Constructs (if necessary) and returns a linear solver. More...

Public Member Functions inherited from oofem::SparseNonLinearSystemNM
	SparseNonLinearSystemNM (Domain d, EngngModel m)
	Constructor. More...

virtual	~SparseNonLinearSystemNM ()
	Destructor. More...

virtual double	giveCurrentStepLength ()
	Returns step length. More...

virtual void	setStepLength (double s)
	Sets the step length. More...

virtual bool	referenceLoad () const
	Returns true if reference loads are used (i.e. More...

IRResultType	initializeFrom (InputRecord *ir)

virtual void	convertPertMap ()

virtual void	applyPerturbation (FloatArray *displacement)

std::string	errorInfo (const char *func) const
	Error printing helper. More...

Public Member Functions inherited from oofem::NumericalMethod
	NumericalMethod (Domain d, EngngModel m)
	Constructor. More...

virtual	~NumericalMethod ()
	Destructor. More...

EngngModel *	giveEngngModel ()

virtual contextIOResultType	saveContext (DataStream &stream, ContextMode mode, void *obj=NULL)

virtual contextIOResultType	restoreContext (DataStream &stream, ContextMode mode, void *obj=NULL)

Protected Types
enum	nrsolver_ModeType { nrsolverModifiedNRM, nrsolverFullNRM, nrsolverAccelNRM }

Protected Member Functions
LineSearchNM *	giveLineSearchSolver ()
	Constructs and returns a line search solver. More...

void	initPrescribedEqs ()
	Initiates prescribed equations. More...

void	applyConstraintsToStiffness (SparseMtrx &k)

void	applyConstraintsToLoadIncrement (int nite, const SparseMtrx &k, FloatArray &R, referenceLoadInputModeType rlm, TimeStep *tStep)

bool	checkConvergence (FloatArray &RT, FloatArray &F, FloatArray &rhs, FloatArray &ddX, FloatArray &X, double RRT, const FloatArray &internalForcesEBENorm, int nite, bool &errorOutOfRange)
	Determines whether or not the solution has reached convergence. More...

Protected Attributes
int	nsmax

int	minIterations

double	minStepLength

nrsolver_ModeType	NR_Mode

nrsolver_ModeType	NR_OldMode

int	NR_ModeTick

int	MANRMSteps

std::unique_ptr< SparseLinearSystemNM >	linSolver
	linear system solver More...

LinSystSolverType	solverType
	linear system solver ID More...

SparseMtrx::SparseMtrxVersionType	smConstraintVersion
	sparse matrix version, used to control constrains application to stiffness More...

int	numberOfPrescribedDofs
	number of prescribed displacement More...

bool	prescribedDofsFlag
	Flag indicating that some dofs are controlled under displacement control. More...

IntArray	prescribedDofs
	Array of pairs identifying prescribed dofs (node, dof) More...

FloatArray	prescribedDofsValues
	Array of prescribed values. More...

int	prescribedDisplacementTF
	Load Time Function of prescribed values. More...

IntArray	prescribedEqs
	Array of prescribed equations. More...

bool	prescribedEqsInitFlag
	Flag indicating that prescribedEqs were initialized. More...

FloatArray	lastReactions
	Computed reactions. They are stored in order to print them in printState method. More...

bool	lsFlag
	Flag indicating whether to use line-search. More...

std::unique_ptr< LineSearchNM >	linesearchSolver
	Line search solver. More...

bool	mCalcStiffBeforeRes
	Flag indicating if the stiffness should be evaluated before the residual in the first iteration. More...

bool	constrainedNRFlag
	Flag indicating whether to use constrained Newton. More...

double	constrainedNRalpha
	Scale factor for dX, dX_new = alpha * dX. More...

int	constrainedNRminiter
	Minimum number of iterations before constraint is activated. More...

FloatArray	rtolf
	Relative unbalanced force tolerance for each group. More...

FloatArray	rtold
	Relative iterative displacement change tolerance for each group. More...

FloatArray	forceErrVec

FloatArray	forceErrVecOld

std::map< int, double >	dg_forceScale
	Optional user supplied scale of forces used in convergence check. More...

double	maxIncAllowed

Protected Attributes inherited from oofem::SparseNonLinearSystemNM
double	deltaL
	Load level. More...

double	randPertAmplitude
	Amplitude of a random perturbation applied on the solution before the iteration process. More...

int	randSeed

bool	pert_init_needed

IntArray	igp_PertDmanDofSrcArray

FloatArray	igp_PertWeightArray

IntArray	igp_Map

FloatArray	igp_Weight

Protected Attributes inherited from oofem::NumericalMethod
Domain *	domain
	Pointer to domain. More...

EngngModel *	engngModel
	Pointer to engineering model. More...

Additional Inherited Members
Public Types inherited from oofem::SparseNonLinearSystemNM
enum	referenceLoadInputModeType { rlm_total =0, rlm_incremental =1 }
	The following parameter allows to specify how the reference load vector is obtained from given totalLoadVector and initialLoadVector. More...

Detailed Description

This class implements Newton-Raphson Method, derived from abstract NumericalMethod class for solving non-linear problems.

Except the traditional load control, it also provides direct displacement control without requiring BC applied, so that the equation renumbering is not required when combining arc-length and Newton-Raphson solvers within a simulation.

The direct displacement control is achieved by adding a large number alpha to the corresponding diagonal member of K and replacing the right-hand side by alpha*prescribed_value. If alpha is very much larger than other stiffness coefficients then this alteration effectively replaces the corresponding equation by alpha*unknown_value = alpha*prescribed_value that is, the required condition, but the whole system remains symmetric and minimal changes are necessary in the computational sequence. The above artifice has been introduced by Payne and Irons.

Definition at line 95 of file nrsolver.h.

Member Enumeration Documentation

enum oofem::NRSolver::nrsolver_ModeType

protected

Enumerator
nrsolverModifiedNRM
nrsolverFullNRM
nrsolverAccelNRM

Definition at line 98 of file nrsolver.h.

Constructor & Destructor Documentation

oofem::NRSolver::NRSolver	(	Domain *	d,
		EngngModel *	m
	)

oofem::NRSolver::~NRSolver ( )

virtual

Definition at line 97 of file nrsolver.C.

Member Function Documentation

void oofem::NRSolver::applyConstraintsToLoadIncrement	(	int	nite,
		const SparseMtrx &	k,
		FloatArray &	R,
		referenceLoadInputModeType	rlm,
		TimeStep *	tStep
	)

protected

void oofem::NRSolver::applyConstraintsToStiffness ( SparseMtrx & k )

protected

Definition at line 454 of file nrsolver.C.

References oofem::IntArray::at(), oofem::SparseMtrx::at(), oofem::PetscSparseMtrx::createVecGlobal(), oofem::PetscSparseMtrx::giveMtrx(), oofem::SparseMtrx::giveVersion(), numberOfPrescribedDofs, prescribedEqs, and smConstraintVersion.

Referenced by solve().

bool oofem::NRSolver::checkConvergence	(	FloatArray &	RT,
		FloatArray &	F,
		FloatArray &	rhs,
		FloatArray &	ddX,
		FloatArray &	X,
		double	RRT,
		const FloatArray &	internalForcesEBENorm,
		int	nite,
		bool &	errorOutOfRange
	)

protected

Determines whether or not the solution has reached convergence.

Returns: True if solution has converged, otherwise false.

Todo:: This is almost always the case for displacement error. nrsolveR_ERROR_NORM_SMALL_NUM is no good.

Definition at line 580 of file nrsolver.C.

References oofem::__DofIDItemToString(), oofem::ParallelContext::accumulate(), oofem::IntArray::at(), oofem::FloatArray::at(), constrainedNRFlag, dg_forceScale, oofem::NumericalMethod::domain, oofem::Element_local, oofem::NumericalMethod::engngModel, forceErrVec, forceErrVecOld, oofem::Domain::giveBcs(), oofem::Domain::giveDofManagers(), oofem::Domain::giveElements(), oofem::Domain::giveMaxDofID(), oofem::Domain::giveNumber(), oofem::EngngModel::giveParallelContext(), oofem::EngngModel::giveProblemScale(), oofem::FloatArray::giveSize(), oofem::ParallelContext::isLocal(), oofem::ParallelContext::localNorm(), oofem::macroScale, nrsolver_ERROR_NORM_SMALL_NUM, NRSOLVER_MAX_REL_ERROR_BOUND, OOFEM_LOG_INFO, oofem::FloatArray::resize(), rtold, rtolf, oofem::FloatArray::zero(), and oofem::IntArray::zero().

Referenced by oofem::DynamicRelaxationSolver::solve(), and solve().

virtual const char* oofem::NRSolver::giveClassName ( ) const

inlinevirtual

Reimplemented from oofem::SparseNonLinearSystemNM.

Reimplemented in oofem::StaggeredSolver, and oofem::DynamicRelaxationSolver.

Definition at line 172 of file nrsolver.h.

virtual const char* oofem::NRSolver::giveInputRecordName ( ) const

inlinevirtual

Reimplemented in oofem::StaggeredSolver, and oofem::DynamicRelaxationSolver.

Definition at line 173 of file nrsolver.h.

References _IFT_NRSolver_Name.

SparseLinearSystemNM * oofem::NRSolver::giveLinearSolver ( )

virtual

Constructs (if necessary) and returns a linear solver.

Public method because some problems require it for sensitivity analysis, etc. even for nonlinear problems (e.g. tangent relations in multiscale simulations).

Reimplemented from oofem::SparseNonLinearSystemNM.

Definition at line 390 of file nrsolver.C.

References oofem::classFactory, oofem::ClassFactory::createSparseLinSolver(), oofem::NumericalMethod::domain, oofem::NumericalMethod::engngModel, linSolver, OOFEM_ERROR, and solverType.

Referenced by initializeFrom(), and solve().

LineSearchNM * oofem::NRSolver::giveLineSearchSolver ( )

protected

Constructs and returns a line search solver.

Definition at line 410 of file nrsolver.C.

References oofem::NumericalMethod::domain, oofem::NumericalMethod::engngModel, and linesearchSolver.

Referenced by initializeFrom(), and solve().

IRResultType oofem::NRSolver::initializeFrom ( InputRecord * ir )

virtual

Reimplemented from oofem::NumericalMethod.

Reimplemented in oofem::StaggeredSolver, and oofem::DynamicRelaxationSolver.

Definition at line 103 of file nrsolver.C.

References _IFT_NRSolver_calcstiffbeforeres, _IFT_NRSolver_constrainedNRminiter, _IFT_NRSolver_ddfunc, _IFT_NRSolver_ddm, _IFT_NRSolver_ddv, _IFT_NRSolver_forceScale, _IFT_NRSolver_forceScaleDofs, _IFT_NRSolver_linesearch, _IFT_NRSolver_lstype, _IFT_NRSolver_manrmsteps, _IFT_NRSolver_maxinc, _IFT_NRSolver_maxiter, _IFT_NRSolver_miniterations, _IFT_NRSolver_minsteplength, _IFT_NRSolver_rtold, _IFT_NRSolver_rtolf, _IFT_NRSolver_rtolv, oofem::FloatArray::at(), oofem::IntArray::clear(), oofem::FloatArray::clear(), constrainedNRFlag, constrainedNRminiter, dg_forceScale, giveLinearSolver(), giveLineSearchSolver(), oofem::IntArray::giveSize(), oofem::FloatArray::giveSize(), oofem::InputRecord::hasField(), oofem::LineSearchNM::initializeFrom(), oofem::NumericalMethod::initializeFrom(), oofem::SparseNonLinearSystemNM::initializeFrom(), IR_GIVE_FIELD, IR_GIVE_OPTIONAL_FIELD, lsFlag, MANRMSteps, maxIncAllowed, mCalcStiffBeforeRes, minIterations, minStepLength, NR_Mode, NR_OldMode, nrsolverAccelNRM, nrsolverModifiedNRM, nsmax, numberOfPrescribedDofs, OOFEM_ERROR, prescribedDisplacementTF, prescribedDofs, prescribedDofsFlag, prescribedDofsValues, oofem::FloatArray::resize(), rtold, rtolf, and solverType.

Referenced by oofem::DynamicRelaxationSolver::initializeFrom(), and oofem::StaggeredSolver::initializeFrom().

void oofem::NRSolver::initPrescribedEqs ( )

protected

Initiates prescribed equations.

Definition at line 420 of file nrsolver.C.

References oofem::IntArray::at(), oofem::NumericalMethod::domain, oofem::NumericalMethod::engngModel, oofem::DofManager::giveDofWithID(), oofem::Dof::giveEquationNumber(), oofem::DofManager::giveGlobalNumber(), oofem::Domain::giveNode(), oofem::Domain::giveNumber(), oofem::Domain::giveNumberOfDofManagers(), oofem::EngngModel::giveParallelContext(), oofem::ParallelContext::isLocal(), numberOfPrescribedDofs, prescribedDofs, prescribedEqs, prescribedEqsInitFlag, and oofem::IntArray::resize().

Referenced by solve().

void oofem::NRSolver::printState ( FILE * outputStream )

virtual

Prints status message of receiver to output stream.

Prints the message corresponding to last solve.

Parameters

outputStream Stream to print state to.

Reimplemented from oofem::SparseNonLinearSystemNM.

Definition at line 558 of file nrsolver.C.

References oofem::IntArray::at(), oofem::FloatArray::at(), oofem::FloatArray::giveSize(), lastReactions, numberOfPrescribedDofs, and prescribedDofs.

virtual void oofem::NRSolver::reinitialize ( )

inlinevirtual

Reinitializes the receiver.

This is used, when topology of problem has changed (for example after adaptive refinement or load transfer in parallel applications). This is necessary for numerical methods, that cache some data between solution steps and that may depend on domain or problem topology. The caching of data by receiver is intended only for speeding up the calculation, but numerical method must be always able to generate this data again. This method clears receiver cached data dependent on topology, when it changes.

Reimplemented from oofem::NumericalMethod.

Definition at line 184 of file nrsolver.h.

virtual void oofem::NRSolver::setDomain ( Domain * d )

inlinevirtual

Reimplemented from oofem::NumericalMethod.

Definition at line 175 of file nrsolver.h.

NM_Status oofem::NRSolver::solve	(	SparseMtrx &	K,
		FloatArray &	R,
		FloatArray *	R0,
		FloatArray &	X,
		FloatArray &	dX,
		FloatArray &	F,
		const FloatArray &	internalForcesEBENorm,
		double &	s,
		referenceLoadInputModeType	rlm,
		int &	nite,
		TimeStep *	tStep
	)

virtual

Solves the given sparse linear system of equations $ s R + R_0 - F(X) = 0 $ .

Total load vector is not passed, it is defined as $ s R + R_0 $ , where s is scale factor.

See also: EngngModel::updateComponent Used to update the stiffness matrix and load vector.

Parameters

K	Coefficient matrix ( $\displaystyle K = \frac{\partial F}{\partial X}$ ; stiffness matrix).
R	Reference incremental RHS (incremental load).
R0	Initial RHS (initial load).
X	Total solution (total displacement).
dX	Increment of solution (incremental displacements).
F	InternalRhs (real internal forces).
internalForcesEBENorm	Norm of internal nodal forces (evaluated on element by element basis) (split into each DOF id).
s	RHS scale factor (load level).
rlm	Reference load mode.
nite	Number of iterations needed.
tStep	Time step to solve for.

Returns: NM_Status value.

Todo:: This doesn't check units, it is nonsense and must be corrected / Mikael

Implements oofem::SparseNonLinearSystemNM.

Reimplemented in oofem::StaggeredSolver, and oofem::DynamicRelaxationSolver.

Definition at line 202 of file nrsolver.C.

Member Data Documentation

double oofem::NRSolver::constrainedNRalpha

protected

Scale factor for dX, dX_new = alpha * dX.

Definition at line 143 of file nrsolver.h.

Referenced by solve().

bool oofem::NRSolver::constrainedNRFlag

protected

Flag indicating whether to use constrained Newton.

Definition at line 141 of file nrsolver.h.

Referenced by checkConvergence(), initializeFrom(), and solve().

int oofem::NRSolver::constrainedNRminiter

protected

Minimum number of iterations before constraint is activated.

Definition at line 145 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

std :: map<int, double> oofem::NRSolver::dg_forceScale

protected

Optional user supplied scale of forces used in convergence check.

Definition at line 157 of file nrsolver.h.

Referenced by checkConvergence(), and initializeFrom().

FloatArray oofem::NRSolver::forceErrVec

protected

Todo:: This doesn't check units, it is nonsense and must be corrected / Mikael

Definition at line 153 of file nrsolver.h.

Referenced by checkConvergence(), and solve().

FloatArray oofem::NRSolver::forceErrVecOld

protected

Definition at line 154 of file nrsolver.h.

Referenced by checkConvergence(), and solve().

FloatArray oofem::NRSolver::lastReactions

protected

Computed reactions. They are stored in order to print them in printState method.

Definition at line 133 of file nrsolver.h.

Referenced by printState(), and solve().

std :: unique_ptr< LineSearchNM > oofem::NRSolver::linesearchSolver

protected

Line search solver.

Definition at line 137 of file nrsolver.h.

Referenced by giveLineSearchSolver().

std :: unique_ptr< SparseLinearSystemNM > oofem::NRSolver::linSolver

protected

linear system solver

Definition at line 107 of file nrsolver.h.

Referenced by giveLinearSolver(), and solve().

bool oofem::NRSolver::lsFlag

protected

Flag indicating whether to use line-search.

Definition at line 135 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

int oofem::NRSolver::MANRMSteps

protected

Definition at line 104 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

double oofem::NRSolver::maxIncAllowed

protected

Definition at line 159 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

bool oofem::NRSolver::mCalcStiffBeforeRes

protected

Flag indicating if the stiffness should be evaluated before the residual in the first iteration.

Definition at line 139 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

int oofem::NRSolver::minIterations

protected

Definition at line 100 of file nrsolver.h.

Referenced by initializeFrom(), oofem::DynamicRelaxationSolver::solve(), and solve().

double oofem::NRSolver::minStepLength

protected

Definition at line 101 of file nrsolver.h.

Referenced by initializeFrom().

nrsolver_ModeType oofem::NRSolver::NR_Mode

protected

Definition at line 102 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

int oofem::NRSolver::NR_ModeTick

protected

Definition at line 103 of file nrsolver.h.

nrsolver_ModeType oofem::NRSolver::NR_OldMode

protected

Definition at line 102 of file nrsolver.h.

Referenced by initializeFrom().

int oofem::NRSolver::nsmax

protected

Definition at line 100 of file nrsolver.h.

Referenced by initializeFrom(), oofem::DynamicRelaxationSolver::solve(), and solve().

int oofem::NRSolver::numberOfPrescribedDofs

protected

number of prescribed displacement

Definition at line 113 of file nrsolver.h.

Referenced by applyConstraintsToLoadIncrement(), applyConstraintsToStiffness(), initializeFrom(), initPrescribedEqs(), printState(), and solve().

int oofem::NRSolver::prescribedDisplacementTF

protected

Load Time Function of prescribed values.

Definition at line 127 of file nrsolver.h.

Referenced by applyConstraintsToLoadIncrement(), and initializeFrom().

IntArray oofem::NRSolver::prescribedDofs

protected

Array of pairs identifying prescribed dofs (node, dof)

Definition at line 123 of file nrsolver.h.

Referenced by initializeFrom(), initPrescribedEqs(), printState(), and solve().

bool oofem::NRSolver::prescribedDofsFlag

protected

Flag indicating that some dofs are controlled under displacement control.

In parallel mode, numberOfPrescribedDofs is local (related to specific partition) so its nonzero value does not mean that there are no prescribed dofs on other partitions.

Definition at line 120 of file nrsolver.h.

Referenced by initializeFrom(), and solve().

FloatArray oofem::NRSolver::prescribedDofsValues

protected

Array of prescribed values.

Definition at line 125 of file nrsolver.h.

Referenced by applyConstraintsToLoadIncrement(), and initializeFrom().

IntArray oofem::NRSolver::prescribedEqs

protected

Array of prescribed equations.

Definition at line 129 of file nrsolver.h.

Referenced by applyConstraintsToLoadIncrement(), applyConstraintsToStiffness(), initPrescribedEqs(), and solve().