org.apache.commons.math.linear
Class QRDecompositionImpl

java.lang.Object
  org.apache.commons.math.linear.QRDecompositionImpl

All Implemented Interfaces:

QRDecomposition

public class QRDecompositionImpl
extends java.lang.Object
implements QRDecomposition

Calculates the QR-decomposition of a matrix. In the QR-decomposition of a matrix A consists of two matrices Q and R that satisfy: A = QR, Q is orthogonal (Q^TQ = I), and R is upper triangular. If A is m×n, Q is m×m and R m×n.

Implemented using Householder reflectors.

Since:

1.2

Version:

$Revision: 620312 $ $Date: 2008-02-10 12:28:59 -0700 (Sun, 10 Feb 2008) $

See Also:

MathWorld, Wikipedia

Constructor Summary

QRDecompositionImpl(RealMatrix matrix)
Calculates the QR decomposition of the given matrix.

Method Summary

RealMatrix	getQ() Returns the matrix Q of the QR-decomposition.
RealMatrix	getR() Returns the matrix R of the QR-decomposition.

Methods inherited from class java.lang.Object

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

Constructor Detail

QRDecompositionImpl

public QRDecompositionImpl(RealMatrix matrix)

Calculates the QR decomposition of the given matrix.

Parameters:

matrix - The matrix to decompose.

Method Detail

getR

public RealMatrix getR()

Returns the matrix R of the QR-decomposition.

Specified by:

getR in interface QRDecomposition

Returns:

the R matrix

getQ

public RealMatrix getQ()

Returns the matrix Q of the QR-decomposition.

Specified by:

getQ in interface QRDecomposition

Returns:

the Q matrix