Contents
sormhr - overwrite the general real M-by-N matrix C with
SIDE = 'L' SIDE = 'R' TRANS = 'N'
SUBROUTINE SORMHR(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C, LDC,
WORK, LWORK, INFO)
CHARACTER * 1 SIDE, TRANS
INTEGER M, N, ILO, IHI, LDA, LDC, LWORK, INFO
REAL A(LDA,*), TAU(*), C(LDC,*), WORK(*)
SUBROUTINE SORMHR_64(SIDE, TRANS, M, N, ILO, IHI, A, LDA, TAU, C,
LDC, WORK, LWORK, INFO)
CHARACTER * 1 SIDE, TRANS
INTEGER*8 M, N, ILO, IHI, LDA, LDC, LWORK, INFO
REAL A(LDA,*), TAU(*), C(LDC,*), WORK(*)
F95 INTERFACE
SUBROUTINE ORMHR(SIDE, [TRANS], [M], [N], ILO, IHI, A, [LDA], TAU, C,
[LDC], [WORK], [LWORK], [INFO])
CHARACTER(LEN=1) :: SIDE, TRANS
INTEGER :: M, N, ILO, IHI, LDA, LDC, LWORK, INFO
REAL, DIMENSION(:) :: TAU, WORK
REAL, DIMENSION(:,:) :: A, C
SUBROUTINE ORMHR_64(SIDE, [TRANS], [M], [N], ILO, IHI, A, [LDA], TAU,
C, [LDC], [WORK], [LWORK], [INFO])
CHARACTER(LEN=1) :: SIDE, TRANS
INTEGER(8) :: M, N, ILO, IHI, LDA, LDC, LWORK, INFO
REAL, DIMENSION(:) :: TAU, WORK
REAL, DIMENSION(:,:) :: A, C
C INTERFACE
#include <sunperf.h>
void sormhr(char side, char trans, int m, int n, int ilo,
int ihi, float *a, int lda, float *tau, float *c,
int ldc, int *info);
void sormhr_64(char side, char trans, long m, long n, long
ilo, long ihi, float *a, long lda, float *tau,
float *c, long ldc, long *info);
sormhr overwrites the general real M-by-N matrix C with
TRANS = 'T': Q**T * C C * Q**T
where Q is a real orthogonal matrix of order nq, with nq = m
if SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the
product of IHI-ILO elementary reflectors, as returned by
SGEHRD:
Q = H(ilo) H(ilo+1) . . . H(ihi-1).
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.
ILO (input)
ILO and IHI must have the same values as in the
previous call of SGEHRD. Q is equal to the unit
matrix except in the submatrix
Q(ilo+1:ihi,ilo+1:ihi). If SIDE = 'L', then 1 <=
ILO <= IHI <= M, if M > 0, and ILO = 1 and IHI =
0, if M = 0; if SIDE = 'R', then 1 <= ILO <= IHI
<= N, if N > 0, and ILO = 1 and IHI = 0, if N = 0.
IHI (input)
See the description of ILO.
A (input) (LDA,M) if SIDE = 'L' (LDA,N) if SIDE = 'R' The
vectors which define the elementary reflectors, as
returned by SGEHRD.
LDA (input)
The leading dimension of the array A. LDA >=
max(1,M) if SIDE = 'L'; LDA >= max(1,N) if SIDE =
'R'.
TAU (input)
(M-1) if SIDE = 'L' (N-1) if SIDE = 'R' TAU(i)
must contain the scalar factor of the elementary
reflector H(i), as returned by SGEHRD.
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 performance 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 ille-
gal value