SORG2R(1) LAPACK routine (version 3.2) SORG2R(1)NAMESORG2R - generates an m by n real matrix Q with orthonormal columns,
SYNOPSIS
SUBROUTINE SORG2R( M, N, K, A, LDA, TAU, WORK, INFO )
INTEGER INFO, K, LDA, M, N
REAL A( LDA, * ), TAU( * ), WORK( * )
PURPOSESORG2R generates an m by n real 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 SGEQRF.
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) REAL 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 SGEQRF 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) REAL array, dimension (K)
TAU(i) must contain the scalar factor of the elementary reflecā
tor H(i), as returned by SGEQRF.
WORK (workspace) REAL array, dimension (N)
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an illegal value
LAPACK routine (version 3.2) November 2008 SORG2R(1)