sopmtr(3P) Sun Performance Library sopmtr(3P)NAMEsopmtr - overwrite the general real M-by-N matrix C with SIDE = 'L'
SIDE = 'R' TRANS = 'N'
SYNOPSIS
SUBROUTINE SOPMTR(SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC, WORK,
INFO)
CHARACTER * 1 SIDE, UPLO, TRANS
INTEGER M, N, LDC, INFO
REAL AP(*), TAU(*), C(LDC,*), WORK(*)
SUBROUTINE SOPMTR_64(SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC, WORK,
INFO)
CHARACTER * 1 SIDE, UPLO, TRANS
INTEGER*8 M, N, LDC, INFO
REAL AP(*), TAU(*), C(LDC,*), WORK(*)
F95 INTERFACE
SUBROUTINE OPMTR(SIDE, UPLO, [TRANS], [M], [N], AP, TAU, C, [LDC],
[WORK], [INFO])
CHARACTER(LEN=1) :: SIDE, UPLO, TRANS
INTEGER :: M, N, LDC, INFO
REAL, DIMENSION(:) :: AP, TAU, WORK
REAL, DIMENSION(:,:) :: C
SUBROUTINE OPMTR_64(SIDE, UPLO, [TRANS], [M], [N], AP, TAU, C, [LDC],
[WORK], [INFO])
CHARACTER(LEN=1) :: SIDE, UPLO, TRANS
INTEGER(8) :: M, N, LDC, INFO
REAL, DIMENSION(:) :: AP, TAU, WORK
REAL, DIMENSION(:,:) :: C
C INTERFACE
#include <sunperf.h>
void sopmtr(char side, char uplo, char trans, int m, int n, float *ap,
float *tau, float *c, int ldc, int *info);
void sopmtr_64(char side, char uplo, char trans, long m, long n, float
*ap, float *tau, float *c, long ldc, long *info);
PURPOSEsopmtr 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 of order nq, with nq = m if SIDE =
'L' and nq = n if SIDE = 'R'. Q is defined as the product of nq-1 ele‐
mentary reflectors, as returned by SSPTRD using packed storage:
if UPLO = 'U', Q = H(nq-1) . . . H(2)H(1);
if UPLO = 'L', Q = H(1)H(2) . . . H(nq-1).
ARGUMENTS
SIDE (input)
= 'L': apply Q or Q**T from the Left;
= 'R': apply Q or Q**T from the Right.
UPLO (input)
= 'U': Upper triangular packed storage used in previous call
to SSPTRD;
= 'L': Lower triangular packed storage used in previous call
to SSPTRD.
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.
AP (input)
dimension
(M*(M+1)/2) if SIDE = 'L'
(N*(N+1)/2) if SIDE = 'R'
The vectors which define the elementary reflectors, as
returned by SSPTRD. AP is modified by the routine but
restored on exit.
TAU (input)
dimension
(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 SSPTRD.
C (input/output)
dimension (LDC,N)
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)
dimension
(N) if SIDE = 'L'
(M) if SIDE = 'R'
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value
6 Mar 2009 sopmtr(3P)
