Reference documentation for deal.II version Git 3df9da0 20160827 08:29:30 0400

#include <deal.II/lac/trilinos_precondition.h>
Classes  
struct  AdditionalData 
Public Member Functions  
void  initialize (const SparseMatrix &matrix, const AdditionalData &additional_data=AdditionalData()) 
Public Member Functions inherited from TrilinosWrappers::PreconditionBase  
PreconditionBase ()  
PreconditionBase (const PreconditionBase &)  
~PreconditionBase ()  
void  clear () 
virtual void  vmult (VectorBase &dst, const VectorBase &src) const 
virtual void  Tvmult (VectorBase &dst, const VectorBase &src) const 
virtual void  vmult (::Vector< double > &dst, const ::Vector< double > &src) const 
virtual void  Tvmult (::Vector< double > &dst, const ::Vector< double > &src) const 
virtual void  vmult (::LinearAlgebra::distributed::Vector< double > &dst, const ::LinearAlgebra::distributed::Vector< double > &src) const 
virtual void  Tvmult (::LinearAlgebra::distributed::Vector< double > &dst, const ::LinearAlgebra::distributed::Vector< double > &src) const 
Epetra_Operator &  trilinos_operator () const 
Public Member Functions inherited from Subscriptor  
Subscriptor ()  
Subscriptor (const Subscriptor &)  
Subscriptor (Subscriptor &&)  
virtual  ~Subscriptor () 
Subscriptor &  operator= (const Subscriptor &) 
Subscriptor &  operator= (Subscriptor &&) 
void  subscribe (const char *identifier=0) const 
void  unsubscribe (const char *identifier=0) const 
unsigned int  n_subscriptions () const 
void  list_subscribers () const 
template<class Archive >  
void  serialize (Archive &ar, const unsigned int version) 
Additional Inherited Members  
Public Types inherited from TrilinosWrappers::PreconditionBase  
typedef ::types::global_dof_index  size_type 
Static Public Member Functions inherited from TrilinosWrappers::PreconditionBase  
static::ExceptionBase &  ExcNonMatchingMaps (std::string arg1) 
Static Public Member Functions inherited from Subscriptor  
static::ExceptionBase &  ExcInUse (int arg1, char *arg2, std::string &arg3) 
static::ExceptionBase &  ExcNoSubscriber (char *arg1, char *arg2) 
Protected Attributes inherited from TrilinosWrappers::PreconditionBase  
std_cxx11::shared_ptr< Epetra_Operator >  preconditioner 
Epetra_MpiComm  communicator 
std_cxx11::shared_ptr< Epetra_Map >  vector_distributor 
A wrapper class for a thresholded incomplete LU factorization (ILUT) preconditioner for Trilinos matrices. This preconditioner works both in serial and in parallel, depending on the matrix it is based on. In general, an incomplete factorization does not take all fillin elements that would appear in a full factorization (that is the basis for a direct solve). For the ILUT preconditioner, the parameter ilut_drop
lets the user specify which elements should be dropped (i.e., should not be part of the incomplete decomposition). Trilinos calculates first the complete factorization for one row, and then skips those elements that are lower than the threshold. This is the main difference to the non thresholded ILU preconditioner, where the parameter ilut_fill
governs the incomplete factorization structure. This parameter is available here as well, but provides only some extra information here.
The AdditionalData data structure allows to set preconditioner options. Besides the fillin arguments, these options are some options for perturbations (see the documentation of the AdditionalData structure for details), and a parameter overlap
that determines if and how much overlap there should be between the matrix partitions on the various MPI processes. The default settings are 0 for the additional fillin, 0 for the absolute augmentation tolerance, 1 for the relative augmentation tolerance, 0 for the overlap.
Note that a parallel application of the ILUT preconditioner is actually a blockJacobi preconditioner with block size equal to the local matrix size. Spoken more technically, this parallel operation is an additive Schwarz method with an ILU approximate solve as inner solver, based on the (outer) parallel partitioning.
Definition at line 1048 of file trilinos_precondition.h.
void TrilinosWrappers::PreconditionILUT::initialize  (  const SparseMatrix &  matrix, 
const AdditionalData &  additional_data = AdditionalData() 

) 
Initialize function. Takes the matrix which is used to form the preconditioner, and additional flags if there are any.
Definition at line 533 of file trilinos_precondition.cc.