CUNML2(3F)CUNML2(3F)NAMECUNML2 - overwrite the general complex m-by-n matrix C with Q * C if
SIDE = 'L' and TRANS = 'N', or Q'* C if SIDE = 'L' and TRANS = 'C', or
C * Q if SIDE = 'R' and TRANS = 'N', or C * Q' if SIDE = 'R' and TRANS
= 'C',
SYNOPSIS
SUBROUTINE CUNML2( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO
)
CHARACTER SIDE, TRANS
INTEGER INFO, K, LDA, LDC, M, N
COMPLEX A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )
PURPOSECUNML2 overwrites the general complex m-by-n matrix C with
where Q is a complex unitary matrix defined as the product of k
elementary reflectors
Q = H(k)' . . . H(2)' H(1)'
as returned by CGELQF. Q is of order m if SIDE = 'L' and of order n if
SIDE = 'R'.
ARGUMENTS
SIDE (input) CHARACTER*1
= 'L': apply Q or Q' from the Left
= 'R': apply Q or Q' from the Right
TRANS (input) CHARACTER*1
= 'N': apply Q (No transpose)
= 'C': apply Q' (Conjugate transpose)
M (input) INTEGER
The number of rows of the matrix C. M >= 0.
N (input) INTEGER
The number of columns of the matrix C. N >= 0.
K (input) INTEGER
The number of elementary reflectors whose product defines the
matrix Q. If SIDE = 'L', M >= K >= 0; if SIDE = 'R', N >= K >=
0.
A (input) COMPLEX array, dimension
(LDA,M) if SIDE = 'L', (LDA,N) if SIDE = 'R' The i-th row must
contain the vector which defines the elementary reflector H(i),
for i = 1,2,...,k, as returned by CGELQF in the first k rows of
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CUNML2(3F)CUNML2(3F)
its array argument A. A is modified by the routine but restored
on exit.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,K).
TAU (input) COMPLEX array, dimension (K)
TAU(i) must contain the scalar factor of the elementary reflector
H(i), as returned by CGELQF.
C (input/output) COMPLEX array, dimension (LDC,N)
On entry, the m-by-n matrix C. On exit, C is overwritten by Q*C
or Q'*C or C*Q' or C*Q.
LDC (input) INTEGER
The leading dimension of the array C. LDC >= max(1,M).
WORK (workspace) COMPLEX array, dimension
(N) if SIDE = 'L', (M) if SIDE = 'R'
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
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