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Member of the linalgebra class.

Syntax

r = qr(a)

[q, r] = qr(a)

[q, r] = qr(a, 0)

[q, r, pm] = qr(a)

[q, r, pv] = qr(a, 0)

Description

Performs the QR decomposition of an input matrix with or without column pivoting.

Details

Examples

Inputs

Name	Description
a	Specifies a matrix.
0	Specifies that LabVIEW computes the economy size QR decomposition such that the size of q is m-by-min(m, n) and the size of r is min(m, n)-by-n, where a is an m-by-n matrix.

Outputs

Name	Description
q	Returns the orthogonal or unitary matrix of the QR decomposition of a.
r	Returns the upper triangular matrix of the QR decomposition of a.
pm	Returns the pivot matrix of the QR decomposition of a. pm is a matrix of 32-bit signed integers.
pv	Returns the pivot vector of the QR decomposition of a. pv is a row vector of 32-bit signed integers.

Details

The QR decomposition of a matrix a without column pivoting computes matrices q and r such that q*r = a, where q is an orthogonal or unitary matrix and r is an upper triangular matrix.

The QR decomposition of a matrix a with column pivoting computes matrices q and r and the pivot matrix pm or the pivot vector pv such that q*r = a*pm or q*r = a(pv). LabVIEW performs column pivoting on a such that the diagonal elements of r are in decreasing order.

Examples

A = rand(2)
[Q, R, P] = qr(A)