sormrq(3P) Sun Performance Library sormrq(3P)NAMEsormrq - overwrite the general real M-by-N matrix C with Q*C or Q**T*C
or C*Q**T or C*Q.
SYNOPSIS
SUBROUTINE SORMRQ(SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
LWORK, INFO)
CHARACTER * 1 SIDE, TRANS
INTEGER M, N, K, LDA, LDC, LWORK, INFO
REAL A(LDA,*), TAU(*), C(LDC,*), WORK(*)
SUBROUTINE SORMRQ_64(SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK,
LWORK, INFO)
CHARACTER * 1 SIDE, TRANS
INTEGER*8 M, N, K, LDA, LDC, LWORK, INFO
REAL A(LDA,*), TAU(*), C(LDC,*), WORK(*)
F95 INTERFACE
SUBROUTINE ORMRQ(SIDE, [TRANS], [M], [N], [K], A, [LDA], TAU, C, [LDC],
[WORK], [LWORK], [INFO])
CHARACTER(LEN=1) :: SIDE, TRANS
INTEGER :: M, N, K, LDA, LDC, LWORK, INFO
REAL, DIMENSION(:) :: TAU, WORK
REAL, DIMENSION(:,:) :: A, C
SUBROUTINE ORMRQ_64(SIDE, [TRANS], [M], [N], [K], A, [LDA], TAU, C,
[LDC], [WORK], [LWORK], [INFO])
CHARACTER(LEN=1) :: SIDE, TRANS
INTEGER(8) :: M, N, K, LDA, LDC, LWORK, INFO
REAL, DIMENSION(:) :: TAU, WORK
REAL, DIMENSION(:,:) :: A, C
C INTERFACE
#include <sunperf.h>
void sormrq(char side, char trans, int m, int n, int k, float *a, int
lda, float *tau, float *c, int ldc, int *info);
void sormrq_64(char side, char trans, long m, long n, long k, float *a,
long lda, float *tau, float *c, long ldc, long *info);
PURPOSEsormrq overwrites the general real M-by-N matrix C with
SIDE = 'L' SIDE = 'R'
TRANS = 'N': Q * C C * Q
TRANS = 'T': Q**T * C C * Q**T
where Q is a real orthogonal matrix defined as the product of k elemen‐
tary reflectors
Q = H(1)H(2) . . . H(k)
as returned by SGERQF. Q is of order M if SIDE = 'L' and of order N if
SIDE = 'R'.
ARGUMENTS
SIDE (input)
= 'L': apply Q or Q**T from the Left;
= 'R': apply Q or Q**T from the Right.
TRANS (input)
= 'N': No transpose, apply Q;
= 'T': Transpose, apply Q**T.
TRANS is defaulted to 'N' for F95 INTERFACE.
M (input) The number of rows of the matrix C. M >= 0.
N (input) The number of columns of the matrix C. N >= 0.
K (input) 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) (LDA,M) if SIDE = 'L', (LDA,N) if SIDE = 'R' The i-th row
must contain the vector which defines the elementary reflec‐
tor H(i), for i = 1,2,...,k, as returned by SGERQF in the
last k rows of its array argument A. A is modified by the
routine but restored on exit.
LDA (input)
The leading dimension of the array A. LDA >= max(1,K).
TAU (input)
TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by SGERQF.
C (input/output)
On entry, the M-by-N matrix C. On exit, C is overwritten by
Q*C or Q**T*C or C*Q**T or C*Q.
LDC (input)
The leading dimension of the array C. LDC >= max(1,M).
WORK (workspace)
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
LWORK (input)
The dimension of the array WORK. If SIDE = 'L', LWORK >=
max(1,N); if SIDE = 'R', LWORK >= max(1,M). For optimum per‐
formance LWORK >= N*NB if SIDE = 'L', and LWORK >= M*NB if
SIDE = 'R', where NB is the optimal blocksize.
If LWORK = -1, then a workspace query is assumed; the routine
only calculates the optimal size of the WORK array, returns
this value as the first entry of the WORK array, and no error
message related to LWORK is issued by XERBLA.
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
6 Mar 2009 sormrq(3P)