DUNE PDELab (2.8)
A parallel SSOR preconditioner. More...
#include <dune/istl/schwarz.hh>
Public Member Functions | |
ParSSOR (const matrix_type &A, int n, field_type w, const communication_type &c) | |
Constructor. More... | |
virtual void | pre (X &x, Y &b) |
Prepare the preconditioner. More... | |
virtual void | apply (X &v, const Y &d) |
Apply the precondtioner. More... | |
virtual void | post (X &x) |
Clean up. More... | |
virtual SolverCategory::Category | category () const |
Category of the preconditioner (see SolverCategory::Category) | |
Detailed Description
class Dune::ParSSOR< M, X, Y, C >
A parallel SSOR preconditioner.
- Template Parameters
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M The type of the sequential matrix to use, e.g. BCRSMatrix or another matrix type fulfilling the matrix interface of ISTL. X The type of the sequential vector to use for the left hand side, e.g. BlockVector or another type fulfilling the ISTL vector interface. Y The type of the sequential vector to use for the right hand side, e..g. BlockVector or another type fulfilling the ISTL vector interface. C The type of the communication object. This must either be OwnerOverlapCopyCommunication or a type implementing the same interface.
Constructor & Destructor Documentation
◆ ParSSOR()
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inline |
Constructor.
constructor gets all parameters to operate the prec.
- Parameters
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A The matrix to operate on. n The number of iterations to perform. w The relaxation factor. c The communication object for syncing overlap and copy data points. (E.~g. OwnerOverlapCopyCommunication )
Member Function Documentation
◆ apply()
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inlinevirtual |
Apply the precondtioner.
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< X, Y >.
References Dune::bsorb(), and Dune::bsorf().
◆ post()
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inlinevirtual |
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
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x The right hand side of the equation.
Implements Dune::Preconditioner< X, Y >.
◆ pre()
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inlinevirtual |
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.
- Note
- if a preconditioner is copied (e.g. for a second thread) again the pre() method has to be called to ensure proper memory mangement.
- Parameters
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x The left hand side of the equation. b The right hand side of the equation.
Implements Dune::Preconditioner< X, Y >.
The documentation for this class was generated from the following file:
- dune/istl/schwarz.hh