DUNE-FEM (unstable)
Turns an InverseOperator into a Preconditioner. More...
#include <dune/istl/preconditioners.hh>
Public Types | |
typedef O::domain_type | domain_type |
The domain type of the preconditioner. | |
typedef O::range_type | range_type |
The range type of the preconditioner. | |
typedef range_type::field_type | field_type |
The field type of the preconditioner. | |
typedef Simd::Scalar< field_type > | scalar_field_type |
scalar type underlying the field_type | |
typedef FieldTraits< scalar_field_type >::real_type | real_field_type |
real scalar type underlying the field_type | |
typedef O | InverseOperator |
type of the wrapped inverse operator | |
Public Member Functions | |
InverseOperator2Preconditioner (InverseOperator &inverse_operator) | |
Construct the preconditioner from the solver. More... | |
void | pre (domain_type &, range_type &) override |
Prepare the preconditioner. More... | |
void | apply (domain_type &v, const range_type &d) override |
Apply one step of the preconditioner to the system A(v)=d. More... | |
void | post (domain_type &) override |
Clean up. More... | |
SolverCategory::Category | category () const override |
Category of the preconditioner (see SolverCategory::Category) | |
Detailed Description
class Dune::InverseOperator2Preconditioner< O, c >
Turns an InverseOperator into a Preconditioner.
- Template Parameters
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O The type of the inverse operator to wrap.
Constructor & Destructor Documentation
◆ InverseOperator2Preconditioner()
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inline |
Construct the preconditioner from the solver.
- Parameters
-
inverse_operator The inverse operator to wrap.
References Dune::SolverCategory::category(), and DUNE_THROW.
Member Function Documentation
◆ apply()
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inlineoverridevirtual |
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 \( v = M^{-1} d \) where \( M \) is the approximate inverse of the operator \( A \) characterizing the preconditioner.
- Parameters
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[out] v The update to be computed d The current defect.
Implements Dune::Preconditioner< O::domain_type, O::range_type >.
◆ post()
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inlineoverridevirtual |
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< O::domain_type, O::range_type >.
◆ pre()
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inlineoverridevirtual |
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.
- Note
- if a preconditioner is copied (e.g. for a second thread) again the pre() method has to be called to ensure proper memory management.
- Parameters
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x The left hand side of the equation. b The right hand side of the equation.
Implements Dune::Preconditioner< O::domain_type, O::range_type >.
The documentation for this class was generated from the following file:
- dune/istl/preconditioners.hh