SORG2L - generate an m by n real matrix Q with orthonormal
columns,
SYNOPSIS
SUBROUTINE SORG2L( M, N, K, A, LDA, TAU, WORK, INFO )
INTEGER INFO, K, LDA, M, N
REAL A( LDA, * ), TAU( * ), WORK( * )
PURPOSE
SORG2L generates an m by n real matrix Q with orthonormal
columns, which is defined as the last n columns of a prod
uct of k elementary reflectors of order m
Q = H(k) . . . H(2) H(1)
as returned by SGEQLF.
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 (n-k+i)-th column must contain the
vector which defines the elementary reflector
H(i), for i = 1,2,...,k, as returned by SGEQLF in
the last 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 ele
mentary reflector H(i), as returned by SGEQLF.
WORK (workspace) REAL array, dimension (N)
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an ille
gal value
Man(1) output converted with
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