Flashnux

GNU/Linux man pages

• CentOS
• Debian
• Red Hat
• Ubuntu
• Unix

Livre :
Expressions régulières,
Syntaxe et mise en oeuvre :

ISBN : 978-2-7460-9712-4
EAN : 9782746097124
(Editions ENI)

GNU/Linux	CentOS 4.8	i386
	cung2r(l)

---

CUNG2R

NAME
SYNOPSIS
PURPOSE
ARGUMENTS

---

NAME

CUNG2R - generate an m by n complex matrix Q with orthonormal columns,

SYNOPSIS

	SUBROUTINE CUNG2R(		M, N, K, A, LDA, TAU, WORK, INFO )
	INTEGER		INFO, K, LDA, M, N
	COMPLEX		A( LDA, * ), TAU( * ), WORK( * )

PURPOSE

CUNG2R generates an m by n complex matrix Q with orthonormal columns, which is defined as the first n columns of a product of k elementary reflectors of order m

Q = H(1) H(2) . . . H(k)

as returned by CGEQRF.

ARGUMENTS

M (input) INTEGER

The number of rows of the matrix Q. M >= 0.

N (input) INTEGER

The number of columns of the matrix Q. M >= N >= 0.

K (input) INTEGER

The number of elementary reflectors whose product defines the matrix Q. N >= K >= 0.

A (input/output) COMPLEX array, dimension (LDA,N)

On entry, the i-th column must contain the vector which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by CGEQRF in the first k columns of its array argument A. On exit, the m by n matrix Q.

LDA (input) INTEGER

The first dimension of the array A. LDA >= max(1,M).

TAU (input) COMPLEX array, dimension (K)

TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by CGEQRF.

WORK (workspace) COMPLEX array, dimension (N)
INFO (output) INTEGER

= 0: successful exit
< 0: if INFO = -i, the i-th argument has an illegal value

---

---

cung2r(l)