template<class X, class Y, class C, class T = Preconditioner<X,Y>>
class Dune::BlockPreconditioner< X, Y, C, T >
Block parallel preconditioner.
This is essentially a wrapper that take a sequential preconditoner. In each step the sequential preconditioner is applied and then all owner data points are updates on all other processes.
template<class X, class Y, class C, class T = Preconditioner<X,Y>>
Apply the preconditioner.
Apply one step of the preconditioner to the system A(v)=d. On entry v=0 and d=b-A(x) (although this might not be computed in that way. On exit v contains the update, i.e one step computes
where
is the approximate inverse of the operator
characterizing the preconditioner.
- Parameters
-
[out] | v | The update to be computed |
| d | The current defect. |
Implements Dune::Preconditioner< X, Y >.
template<class X, class Y, class C, class T = Preconditioner<X,Y>>
template<bool forward>
Apply one step of the preconditioner to the system A(v)=d.
On entry v=0 and d=b-A(x) (although this might not be computed in that way. On exit v contains the update, i.e one step computes
where
is the approximate inverse of the operator
characterizing the preconditioner.
- Parameters
-
[out] | v | The update to be computed |
| d | The current defect. |
Implements Dune::Preconditioner< X, Y >.
template<class X, class Y, class C, class T = Preconditioner<X,Y>>
Clean up.
Clean up. This method is called after the last apply call for the linear system to be solved. Memory may be deallocated safely here. x is the solution of the linear equation.
- Parameters
-
x | The right hand side of the equation. |
Implements Dune::Preconditioner< X, Y >.
template<class X, class Y, class C, class T = Preconditioner<X,Y>>
Prepare the preconditioner.
Prepare the preconditioner. A solver solves a linear operator equation A(x)=b by applying one or several steps of the preconditioner. The method pre() is called before the first apply operation. b and x are right hand side and solution vector of the linear system respectively. It may. e.g., scale the system, allocate memory or compute a (I)LU decomposition. Note: The ILU decomposition could also be computed in the constructor or with a separate method of the derived method if several linear systems with the same matrix are to be solved.
- Parameters
-
x | The left hand side of the equation. |
b | The right hand side of the equation. |
Implements Dune::Preconditioner< X, Y >.