gsCompositePrecOp< T > Class Template Reference

Detailed Description

template<class T>
class gismo::gsCompositePrecOp< T >

This class represents the composition of preconditioners of type gsPreconditionerOp.

If the preconditioners have the iteration matrices \( I-P_iA \), the overall preconditioner has the iteration matrix \( (I-P_nA)\cdots (I-P_1A) \)

This should not be confused with gsProductOp, which would yield

\( I - P_n \cdots P_1 A \).

Inheritance diagram for gsCompositePrecOp< T >:

Collaboration diagram for gsCompositePrecOp< T >:

Public Types
typedef gsLinearOperator< T >	Base
	Base class.
typedef memory::shared_ptr < gsCompositePrecOp >	Ptr
	Shared pointer for gsCompositePrecOp.
typedef memory::unique_ptr < gsCompositePrecOp >	uPtr
	Unique pointer for gsCompositePrecOp.

Public Member Functions
void	addOperator (BasePtr op)
	Add another operator at the end.
void	apply (const gsMatrix< T > &input, gsMatrix< T > &x) const
	apply the operator on the input vector and store the result in x More...
index_t	cols () const
	Returns the number of columns of the operator.
T	estimateLargestEigenvalueOfPreconditionedSystem (index_t steps=10) const
	Estimates the largest eigenvalue of \( PA \). More...
	gsCompositePrecOp ()
	Empty constructor. To be filled with addOperator()
	gsCompositePrecOp (std::vector< BasePtr > ops)
	Constructor taking a vector of preconditioners.
	gsCompositePrecOp (BasePtr op0, BasePtr op1)
	Convenience constructor taking two preconditioners.
	gsCompositePrecOp (BasePtr op0, BasePtr op1, BasePtr op2)
	Convenience constructor taking three preconditioners.
index_t	numOfSweeps ()
	Get the number of sweeps to be applied in the member function apply.
index_t	rows () const
	Returns the number of rows of the operator.
void	setNumOfSweeps (index_t n)
	Set the number of sweeps to be applied in the member function apply.
virtual void	setOptions (const gsOptionList &opt)
	Set options based on a gsOptionList object.
virtual void	step (const gsMatrix< T > &rhs, gsMatrix< T > &x) const
	Apply the smoother for the equation Ax=rhs and update the current iterate x.
virtual void	stepT (const gsMatrix< T > &rhs, gsMatrix< T > &x) const
	Apply the transposed smoother for the equation Ax=rhs and update the current iterate x.
gsLinearOperator< T >::Ptr	underlyingOp () const
	Return the underlying operator \( A \).

Static Public Member Functions
static gsOptionList	defaultOptions ()
	Get the default options as gsOptionList object.
static gsIdentityOp< T >	Identity (const index_t dim)
	Identity operator.
static uPtr	make (std::vector< BasePtr > ops)
	Make command returning a smart pointer.
static uPtr	make (BasePtr op0, BasePtr op1)
	Make command returning a smart pointer.
static uPtr	make (BasePtr op0, BasePtr op1, BasePtr op2)
	Make command returning a smart pointer.

Member Function Documentation

void apply ( const gsMatrix< T > &  input, gsMatrix< T > &  x  ) const

inlinevirtualinherited

apply the operator on the input vector and store the result in x

Parameters

input	Input vector
x	result vector

Implements gsLinearOperator< T >.

Reimplemented in gsPreconditionerFromOp< T >.

T estimateLargestEigenvalueOfPreconditionedSystem ( index_t  steps = 10 ) const

inlineinherited

Estimates the largest eigenvalue of \( PA \).

Parameters

steps

Number of steps to be performed.