Apache Commons Math 3.6.1 · org.apache.commons.math3.linear.JacobiPreconditioner

Modifier and Type	Field and Description
private final ArrayRealVector	diag The diagonal coefficients of the preconditioner.

Access	Constructor and Description
public	JacobiPreconditioner(final double[] the diagonal coefficients of the linear operator to be preconditioned diag, final boolean `true` if a deep copy of the above array should be performed deep) Creates a new instance of this class.

Method Summary

Modifier and Type	Method and Description
public static JacobiPreconditioner	Returns: the diagonal preconditioner made of the inverse of the diagonal coefficients of the specified linear operator create(final RealLinearOperator the linear operator for which the preconditioner should be built a) Creates a new instance of this class.
public int	getColumnDimension() Implements abstract org.apache.commons.math3.linear.RealLinearOperator.getColumnDimension. Returns the dimension of the domain of this operator.
public int	getRowDimension() Implements abstract org.apache.commons.math3.linear.RealLinearOperator.getRowDimension. Returns the dimension of the codomain of this operator.
public RealVector	operate(final RealVector the vector to operate on x) Implements abstract org.apache.commons.math3.linear.RealLinearOperator.operate. Returns the result of multiplying `this` by the vector `x`.
public RealLinearOperator	Returns: the square root of `this` preconditioner sqrt() Returns the square root of `this` diagonal operator.

Inherited from org.apache.commons.math3.linear.RealLinearOperator:: isTransposable operateTranspose

diag	back to summary
private final ArrayRealVector diag The diagonal coefficients of the preconditioner.

JacobiPreconditioner	back to summary
public JacobiPreconditioner(final double[] diag, final boolean deep) Creates a new instance of this class. Parameters diag:double[] the diagonal coefficients of the linear operator to be preconditioned deep:boolean `true` if a deep copy of the above array should be performed

Method Detail

create back to summary

create	back to summary
public static JacobiPreconditioner create(final RealLinearOperator a) throws NonSquareOperatorException Creates a new instance of this class. This method extracts the diagonal coefficients of the specified linear operator. If `a` does not extend `AbstractRealMatrix`, then the coefficients of the underlying matrix are not accessible, coefficient extraction is made by matrix-vector products with the basis vectors (and might therefore take some time). With matrices, direct entry access is carried out. Parameters a:RealLinearOperator the linear operator for which the preconditioner should be built Returns:JacobiPreconditioner the diagonal preconditioner made of the inverse of the diagonal coefficients of the specified linear operator Exceptions NonSquareOperatorException: if `a` is not square

public static JacobiPreconditioner create(final RealLinearOperator a) throws NonSquareOperatorException

Creates a new instance of this class. This method extracts the diagonal coefficients of the specified linear operator. If a does not extend AbstractRealMatrix, then the coefficients of the underlying matrix are not accessible, coefficient extraction is made by matrix-vector products with the basis vectors (and might therefore take some time). With matrices, direct entry access is carried out.

Parameters

a:RealLinearOperator: the linear operator for which the preconditioner should be built

Returns:JacobiPreconditioner

the diagonal preconditioner made of the inverse of the diagonal coefficients of the specified linear operator

Exceptions

NonSquareOperatorException:: if a is not square

getColumnDimension	back to summary
public int getColumnDimension() Implements abstract org.apache.commons.math3.linear.RealLinearOperator.getColumnDimension. Doc from org.apache.commons.math3.linear.RealLinearOperator.getColumnDimension. Returns the dimension of the domain of this operator. Returns:int the number of columns of the underlying matrix Annotations @Override

getColumnDimension

back to summary

public int getColumnDimension()

Implements abstract org.apache.commons.math3.linear.RealLinearOperator.getColumnDimension.

Doc from org.apache.commons.math3.linear.RealLinearOperator.getColumnDimension.

Returns the dimension of the domain of this operator.

Returns:int

the number of columns of the underlying matrix

Annotations

@Override

getRowDimension	back to summary
public int getRowDimension() Implements abstract org.apache.commons.math3.linear.RealLinearOperator.getRowDimension. Doc from org.apache.commons.math3.linear.RealLinearOperator.getRowDimension. Returns the dimension of the codomain of this operator. Returns:int the number of rows of the underlying matrix Annotations @Override

getRowDimension

back to summary

public int getRowDimension()

Implements abstract org.apache.commons.math3.linear.RealLinearOperator.getRowDimension.

Doc from org.apache.commons.math3.linear.RealLinearOperator.getRowDimension.

Returns the dimension of the codomain of this operator.

Returns:int

the number of rows of the underlying matrix

Annotations

@Override

operate back to summary

operate	back to summary
public RealVector operate(final RealVector x) Implements abstract org.apache.commons.math3.linear.RealLinearOperator.operate. Doc from org.apache.commons.math3.linear.RealLinearOperator.operate. Returns the result of multiplying `this` by the vector `x`. Parameters x:RealVector the vector to operate on Returns:RealVector the product of `this` instance with `x` Annotations @Override

public RealVector operate(final RealVector x)

Implements abstract org.apache.commons.math3.linear.RealLinearOperator.operate.

Doc from org.apache.commons.math3.linear.RealLinearOperator.operate.

Returns the result of multiplying this by the vector x.

Parameters

x:RealVector: the vector to operate on

Returns:RealVector

the product of this instance with x

Annotations

@Override

sqrt back to summary

sqrt	back to summary
public RealLinearOperator sqrt() Returns the square root of `this` diagonal operator. More precisely, this method returns P = diag(1 / √A₁₁, 1 / √A₂₂, …). Returns:RealLinearOperator the square root of `this` preconditioner Since 3.1

public RealLinearOperator sqrt()

Returns the square root of this diagonal operator. More precisely, this method returns P = diag(1 / √A₁₁, 1 / √A₂₂, …).

Returns:RealLinearOperator: the square root of this preconditioner
Since: 3.1

public Class JacobiPreconditioner

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail