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java.lang.Objectno.uib.cipr.matrix.sparse.AMG
public class AMG
Algebraic multigrid preconditioner. Uses the smoothed aggregation method described by Vanek, Mandel, and Brezina (1996).
Constructor Summary | |
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AMG()
Sets up the algebraic multigrid preconditioner using some default parameters. |
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AMG(double omegaPreF,
double omegaPreR,
double omegaPostF,
double omegaPostR,
int nu1,
int nu2,
int gamma,
int min,
double omega)
Sets up the algebraic multigrid preconditioner |
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AMG(double omegaPre,
double omegaPost,
int nu1,
int nu2,
int gamma,
int min,
double omega)
Sets up the algebraic multigrid preconditioner. |
Method Summary | |
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Vector |
apply(Vector b,
Vector x)
Solves the approximate problem with the given right hand side. |
void |
setMatrix(Matrix A)
Sets the operator matrix for the preconditioner. |
Vector |
transApply(Vector b,
Vector x)
Solves the approximate transpose problem with the given right hand side. |
Methods inherited from class java.lang.Object |
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clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Constructor Detail |
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public AMG(double omegaPreF, double omegaPreR, double omegaPostF, double omegaPostR, int nu1, int nu2, int gamma, int min, double omega)
omegaPreF
- Overrelaxation parameter in the forward sweep of the
pre-smoothingomegaPreR
- Overrelaxation parameter in the backwards sweep of the
pre-smoothingomegaPostF
- Overrelaxation parameter in the forward sweep of the
post-smoothingomegaPostR
- Overrelaxation parameter in the backwards sweep of the
post-smoothingnu1
- Number of pre-relaxations to performnu2
- Number of post-relaxations to performgamma
- Number of times to go to a coarser levelmin
- Smallest matrix size before using a direct solveromega
- Jacobi damping parameter, between zero and one. If it equals
zero, the method reduces to the standard aggregate multigrid
methodpublic AMG(double omegaPre, double omegaPost, int nu1, int nu2, int gamma, int min, double omega)
omegaPre
- Overrelaxation parameter in the pre-smoothingomegaPost
- Overrelaxation parameter in the post-smoothingnu1
- Number of pre-relaxations to performnu2
- Number of post-relaxations to performgamma
- Number of times to go to a coarser levelmin
- Smallest matrix size before using a direct solveromega
- Jacobi damping parameter, between zero and one. If it equals
zero, the method reduces to the standard aggregate multigrid
methodpublic AMG()
omegaF=1
and
omegaR=1.85
, while in the postsmoothing,
omegaF=1.85
and omegaR=1
. Sets
nu1=nu2=gamma=1
, has a smallest matrix size of 40, and
sets omega=2/3
.
Method Detail |
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public Vector apply(Vector b, Vector x)
Preconditioner
apply
in interface Preconditioner
b
- Right hand side of problemx
- Result is stored here
public Vector transApply(Vector b, Vector x)
Preconditioner
transApply
in interface Preconditioner
b
- Right hand side of problemx
- Result is stored here
public void setMatrix(Matrix A)
Preconditioner
setMatrix
in interface Preconditioner
A
- Matrix to setup the preconditioner for. Not modified
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