org.ejml.alg.dense.linsol.qr

Class LinearSolverQrHouseCol_D64

java.lang.Object

org.ejml.alg.dense.linsol.LinearSolverAbstract_D64

org.ejml.alg.dense.linsol.qr.LinearSolverQrHouseCol_D64

All Implemented Interfaces:

org.ejml.interfaces.linsol.LinearSolver<org.ejml.data.DenseMatrix64F>

public class LinearSolverQrHouseCol_D64
extends LinearSolverAbstract_D64

QR decomposition can be used to solve for systems. However, this is not as computationally efficient as LU decomposition and costs about 3n² flops.

It solve for x by first multiplying b by the transpose of Q then solving for the result.
QRx=b
Rx=Q^T b

A column major decomposition is used in this solver.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	maxCols
protected int	maxRows

Fields inherited from class org.ejml.alg.dense.linsol.LinearSolverAbstract_D64

A, numCols, numRows

Constructor Summary

Constructors

Constructor and Description
LinearSolverQrHouseCol_D64() Creates a linear solver that uses QR decomposition.

Method Summary

Modifier and Type	Method and Description
org.ejml.interfaces.decomposition.QRDecomposition<org.ejml.data.DenseMatrix64F>	getDecomposition()
boolean	modifiesA()
boolean	modifiesB()
double	quality()
boolean	setA(org.ejml.data.DenseMatrix64F A) Performs QR decomposition on A
void	setMaxSize(int maxRows, int maxCols)
void	solve(org.ejml.data.DenseMatrix64F B, org.ejml.data.DenseMatrix64F X) Solves for X using the QR decomposition.

Methods inherited from class org.ejml.alg.dense.linsol.LinearSolverAbstract_D64

_setA, getA, invert

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

maxRows

protected int maxRows

maxCols

protected int maxCols

Constructor Detail

LinearSolverQrHouseCol_D64

public LinearSolverQrHouseCol_D64()

Creates a linear solver that uses QR decomposition.

Method Detail

setMaxSize

public void setMaxSize(int maxRows,
                       int maxCols)

setA

public boolean setA(org.ejml.data.DenseMatrix64F A)

Performs QR decomposition on A

Parameters:

A - not modified.

quality

public double quality()

solve

public void solve(org.ejml.data.DenseMatrix64F B,
                  org.ejml.data.DenseMatrix64F X)

Solves for X using the QR decomposition.

Parameters:

B - A matrix that is n by m. Not modified.

X - An n by m matrix where the solution is written to. Modified.

modifiesA

public boolean modifiesA()

modifiesB

public boolean modifiesB()

getDecomposition

public org.ejml.interfaces.decomposition.QRDecomposition<org.ejml.data.DenseMatrix64F> getDecomposition()