LinearAlgebra Namespace Reference

Namespaces
namespace	distributed
namespace	EpetraWrappers
namespace	TpetraWrappers

Classes
class	ReadWriteVector

Enumerations
enum class	OrthogonalizationStrategy { modified_gram_schmidt , classical_gram_schmidt , delayed_classical_gram_schmidt }

Functions
template<typename VectorType >
void	set_zero_mean_value (VectorType &vector)

Enumeration Type Documentation

OrthogonalizationStrategy

enum class LinearAlgebra::OrthogonalizationStrategy

strong

Supported orthogonalization strategies within SolverGMRES and SolverFGMRES.

Enumerator
modified_gram_schmidt	Use modified Gram-Schmidt algorithm.
classical_gram_schmidt	Use classical Gram-Schmidt algorithm. Since this approach works on multi-vectors with a single global reduction (of multiple elements), it is more efficient than the modified Gram-Schmidt algorithm. However, it is less stable in terms of roundoff error propagation, requiring additional re-orthogonalization steps more frequently.
delayed_classical_gram_schmidt	Use classical Gram-Schmidt algorithm with two orthogonalization iterations and delayed orthogonalization using the algorithm described in [35]. This approach works on multi-vectors with a single global reduction (of multiple elements) and is more efficient than the modified Gram-Schmidt algorithm. At the same time, it unconditionally performs the second orthogonalization step, making it more stable than the classical Gram-Schmidt variant. For deal.II's own vectors, there is no additional cost compared to the classical Gram-Schmidt algorithm, because the second orthogonalization step is done on cached data. For these beneficial reasons, this is the default algorithm in the SolverGMRES class.

Definition at line 27 of file orthogonalization.h.

Function Documentation

set_zero_mean_value()

template<typename VectorType >

void LinearAlgebra::set_zero_mean_value

(

VectorType &

vector

)

Shift all entries of the vector by a constant factor so that the mean value of the vector becomes zero.

Definition at line 33 of file vector_space_vector.h.