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Belos::CGIter< ScalarType, MV, OP > Class Template Reference

This class implements the preconditioned Conjugate Gradient (CG) iteration. More...

#include <BelosCGIter.hpp>

Inheritance diagram for Belos::CGIter< ScalarType, MV, OP >:
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Public Types

using MVT = MultiVecTraits< ScalarType, MV >
 
using OPT = OperatorTraits< ScalarType, MV, OP >
 
using SCT = Teuchos::ScalarTraits< ScalarType >
 
using MagnitudeType = typename SCT::magnitudeType
 

Public Member Functions

Constructors/Destructor
 CGIter (const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &problem, const Teuchos::RCP< OutputManager< ScalarType > > &printer, const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > &tester, const Teuchos::RCP< StatusTestGenResNorm< ScalarType, MV, OP > > &convTester, Teuchos::ParameterList &params)
 CGIter constructor with linear problem, solver utilities, and parameter list of solver options. More...
 
virtual ~CGIter ()=default
 Destructor. More...
 
Solver methods
void iterate ()
 This method performs CG iterations until the status test indicates the need to stop or an error occurs (in which case, an std::exception is thrown). More...
 
void initializeCG (Teuchos::RCP< CGIterationStateBase< ScalarType, MV > > newstate, Teuchos::RCP< MV > R_0)
 Initialize the solver to an iterate, providing a complete state. More...
 
void initialize ()
 Initialize the solver with the initial vectors from the linear problem or random data. More...
 
Teuchos::RCP
< CGIterationStateBase
< ScalarType, MV > > 		getState () const
 Get the current state of the linear solver. More...
 
void setState (Teuchos::RCP< CGIterationStateBase< ScalarType, MV > > state)
 
Status methods
int getNumIters () const
 Get the current iteration count. More...
 
void resetNumIters (int iter=0)
 Reset the iteration count. More...
 
Teuchos::RCP< const MV > getNativeResiduals (std::vector< MagnitudeType > *norms) const
 Get the norms of the residuals native to the solver. More...
 
Teuchos::RCP< MV > getCurrentUpdate () const
 Get the current update to the linear system. More...
 
Accessor methods
const LinearProblem
< ScalarType, MV, OP > & 		getProblem () const
 Get a constant reference to the linear problem. More...
 
int getBlockSize () const
 Get the blocksize to be used by the iterative solver in solving this linear problem. More...
 
void setBlockSize (int blockSize)
 Set the blocksize to be used by the iterative solver in solving this linear problem. More...
 
bool isInitialized ()
 States whether the solver has been initialized or not. More...
 
void setDoCondEst (bool val)
 Sets whether or not to store the diagonal for condition estimation. More...
 
Teuchos::ArrayView< MagnitudeType > getDiag ()
 Gets the diagonal for condition estimation. More...
 
Teuchos::ArrayView< MagnitudeType > getOffDiag ()
 Gets the off-diagonal for condition estimation. More...
 
State methods
- Public Member Functions inherited from Belos::Iteration< ScalarType, MV, OP >
 Iteration ()
 Default Constructor. More...
 
virtual ~Iteration ()
 Destructor. More...
 
virtual Teuchos::RCP< const MV > getNativeResiduals (std::vector< typename Teuchos::ScalarTraits< ScalarType >::magnitudeType > *norms) const =0
 Get the residuals native to the solver. More...
 

Detailed Description

template<class ScalarType, class MV, class OP>
class Belos::CGIter< ScalarType, MV, OP >

This class implements the preconditioned Conjugate Gradient (CG) iteration.

Author
Teri Barth and Heidi Thornquist

Definition at line 94 of file BelosCGIter.hpp.

Member Typedef Documentation

template<class ScalarType , class MV , class OP >
using Belos::CGIter< ScalarType, MV, OP >::MVT = MultiVecTraits<ScalarType, MV>

Definition at line 101 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
using Belos::CGIter< ScalarType, MV, OP >::OPT = OperatorTraits<ScalarType, MV, OP>

Definition at line 102 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
using Belos::CGIter< ScalarType, MV, OP >::SCT = Teuchos::ScalarTraits<ScalarType>

Definition at line 103 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
using Belos::CGIter< ScalarType, MV, OP >::MagnitudeType = typename SCT::magnitudeType

Definition at line 104 of file BelosCGIter.hpp.

Constructor & Destructor Documentation

template<class ScalarType , class MV , class OP >
Belos::CGIter< ScalarType, MV, OP >::CGIter ( const Teuchos::RCP< LinearProblem< ScalarType, MV, OP > > &  problem,
const Teuchos::RCP< OutputManager< ScalarType > > &  printer,
const Teuchos::RCP< StatusTest< ScalarType, MV, OP > > &  tester,
const Teuchos::RCP< StatusTestGenResNorm< ScalarType, MV, OP > > &  convTester,
Teuchos::ParameterList &  params 
)

CGIter constructor with linear problem, solver utilities, and parameter list of solver options.

This constructor takes pointers required by the linear solver iteration, in addition to a parameter list of options for the linear solver.

Definition at line 335 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
virtual Belos::CGIter< ScalarType, MV, OP >::~CGIter ( )
virtualdefault

Destructor.

Member Function Documentation

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::iterate ( )
virtual

This method performs CG iterations until the status test indicates the need to stop or an error occurs (in which case, an std::exception is thrown).

iterate() will first determine whether the solver is initialized; if not, it will call initialize() using default arguments. After initialization, the solver performs CG iterations until the status test evaluates as Passed, at which point the method returns to the caller.

The status test is queried at the beginning of the iteration.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 415 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::initializeCG ( Teuchos::RCP< CGIterationStateBase< ScalarType, MV > >  newstate,
Teuchos::RCP< MV >  R_0 
)
virtual

Initialize the solver to an iterate, providing a complete state.

The CGIter contains a certain amount of state, consisting of the current residual, preconditioned residual, and decent direction.

initialize() gives the user the opportunity to manually set these, although only the current unpreconditioned residual is required.

Postcondition
isInitialized() == true (see post-conditions of isInitialize())
Note
For any pointer in newstate which directly points to the multivectors in the solver, the data is not copied.

Implements Belos::CGIteration< ScalarType, MV, OP >.

Definition at line 357 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::initialize ( )
inlinevirtual

Initialize the solver with the initial vectors from the linear problem or random data.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 161 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP<CGIterationStateBase<ScalarType,MV> > Belos::CGIter< ScalarType, MV, OP >::getState ( ) const
inlinevirtual

Get the current state of the linear solver.

The data is only valid if isInitialized() == true.

Returns
A CGIterationState object containing const pointers to the current solver state.

Implements Belos::CGIteration< ScalarType, MV, OP >.

Definition at line 172 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::setState ( Teuchos::RCP< CGIterationStateBase< ScalarType, MV > >  state)
inlinevirtual

Implements Belos::CGIteration< ScalarType, MV, OP >.

Definition at line 182 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
int Belos::CGIter< ScalarType, MV, OP >::getNumIters ( ) const
inlinevirtual

Get the current iteration count.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 198 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::resetNumIters ( int  iter = 0)
inlinevirtual

Reset the iteration count.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 201 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP<const MV> Belos::CGIter< ScalarType, MV, OP >::getNativeResiduals ( std::vector< MagnitudeType > *  norms) const
inline

Get the norms of the residuals native to the solver.

Returns
A std::vector of length blockSize containing the native residuals.

Definition at line 205 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::RCP<MV> Belos::CGIter< ScalarType, MV, OP >::getCurrentUpdate ( ) const
inlinevirtual

Get the current update to the linear system.

Note
This method returns a null pointer because the linear problem is current.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 216 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
const LinearProblem<ScalarType,MV,OP>& Belos::CGIter< ScalarType, MV, OP >::getProblem ( ) const
inlinevirtual

Get a constant reference to the linear problem.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 224 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
int Belos::CGIter< ScalarType, MV, OP >::getBlockSize ( ) const
inlinevirtual

Get the blocksize to be used by the iterative solver in solving this linear problem.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 227 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::setBlockSize ( int  blockSize)
inlinevirtual

Set the blocksize to be used by the iterative solver in solving this linear problem.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 230 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
bool Belos::CGIter< ScalarType, MV, OP >::isInitialized ( )
inlinevirtual

States whether the solver has been initialized or not.

Implements Belos::Iteration< ScalarType, MV, OP >.

Definition at line 236 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
void Belos::CGIter< ScalarType, MV, OP >::setDoCondEst ( bool  val)
inlinevirtual

Sets whether or not to store the diagonal for condition estimation.

Implements Belos::CGIteration< ScalarType, MV, OP >.

Definition at line 240 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::ArrayView<MagnitudeType> Belos::CGIter< ScalarType, MV, OP >::getDiag ( )
inlinevirtual

Gets the diagonal for condition estimation.

Implements Belos::CGIteration< ScalarType, MV, OP >.

Definition at line 245 of file BelosCGIter.hpp.

template<class ScalarType , class MV , class OP >
Teuchos::ArrayView<MagnitudeType> Belos::CGIter< ScalarType, MV, OP >::getOffDiag ( )
inlinevirtual

Gets the off-diagonal for condition estimation.

Implements Belos::CGIteration< ScalarType, MV, OP >.

Definition at line 258 of file BelosCGIter.hpp.

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