Public Member Functions | Public Attributes

TrilinosWrappers::PreconditionSOR::AdditionalData Struct Reference

List of all members.

Public Member Functions

 AdditionalData (const double omega=1, const double min_diagonal=0, const unsigned int overlap=0)

Public Attributes

double omega
double min_diagonal
unsigned int overlap

Detailed Description

Standardized data struct to pipe additional flags to the preconditioner. The parameter omega specifies the relaxation parameter in the SOR preconditioner. The parameter min_diagonal can be used to make the application of the preconditioner also possible when some diagonal elements are zero. In a default application this would mean that we divide by zero, so by setting the parameter min_diagonal to a small nonzero value the SOR will work on a matrix that is not too far away from the one we want to treat. Finally, overlap governs the overlap of the partitions when the preconditioner runs in parallel, forming a so-called additive Schwarz preconditioner.

Definition at line 464 of file trilinos_precondition.h.


Constructor & Destructor Documentation

TrilinosWrappers::PreconditionSOR::AdditionalData::AdditionalData ( const double  omega = 1,
const double  min_diagonal = 0,
const unsigned int  overlap = 0 
)

Constructor. By default, set the damping parameter to one, we do not modify the diagonal, and there is no overlap (i.e. in parallel, we run a BlockJacobi preconditioner, where each block is inverted approximately by an SOR.


Member Data Documentation

This specifies the (over-) relaxation parameter in the SOR preconditioner.

Definition at line 486 of file trilinos_precondition.h.

This specifies the minimum value the diagonal elements should have. This might be necessary when the SOR preconditioner is used on matrices with zero diagonal elements. In that case, a straight-forward application would not be possible since we divide by the diagonal element.

Definition at line 501 of file trilinos_precondition.h.

This determines how large the overlap of the local matrix portions on each processor in a parallel application should be.

Definition at line 510 of file trilinos_precondition.h.


The documentation for this struct was generated from the following file:
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Defines

deal.II documentation generated on Fri Feb 3 2012 06:04:17 by doxygen 1.7.2