Reference documentation for deal.II version 9.4.0

#include <deal.II/lac/trilinos_precondition.h>

## Public Member Functions

AdditionalData (const unsigned int block_size=1, const std::string &block_creation_type="linear", const double omega=1, const double min_diagonal=0, const unsigned int overlap=0, const unsigned int n_sweeps=1)

## Public Attributes

unsigned int block_size

std::string block_creation_type

double omega

double min_diagonal

unsigned int overlap

unsigned int n_sweeps

## Detailed Description

Standardized data struct to pipe additional flags to the preconditioner. The parameter block_size sets the size of small blocks. It is recommended to choose this parameter not too large (a few hundreds at most) since this implementation uses a dense matrix for the block. The parameter block_creation_type allows to pass the strategy for finding the blocks to Ifpack. The parameter omega specifies the relaxation parameter in the SSOR 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 642 of file trilinos_precondition.h.

The documentation for this struct was generated from the following files: