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template<typename T>
void opmtr(char *side, char *uplo, char *trans, integer *m, integer *n, T *ap, T *tau, T *c, integer *ldc, T *work, integer *info)# OPMTR overwrites the general real M-by-N matrix.
Purpose:
OPMTR 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 elementary 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).
- Parameters:
SIDE – [in]
SIDE is CHARACTER*1
= ‘L’: apply Q or Q**T from the Left;
= ‘R’: apply Q or Q**T from the Right.UPLO – [in]
UPLO is CHARACTER*1
= ‘U’: Upper triangular packed storage used in previous call to SSPTRD;
= ‘L’: Lower triangular packed storage used in previous call to SSPTRD.TRANS – [in]
TRANS is CHARACTER*1
= ‘N’: No transpose, apply Q;
= ‘T’: Transpose, apply Q**T.M – [in]
M is INTEGER
The number of rows of the matrix C. M >= 0.
N – [in]
N is INTEGER
The number of columns of the matrix C. N >= 0.
AP – [in]
AP is REAL array, 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 – [in]
TAU is REAL array, dimension (M-1) if SIDE = ‘L’ or (N-1) if SIDE = ‘R’
TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by SSPTRD.
C – [inout]
C is REAL array, 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 – [in]
LDC is INTEGER
The leading dimension of the array C. LDC >= fla_max(1,M).
WORK – [out]
WORK is REAL array, dimension
(N) if SIDE = ‘L’
(M) if SIDE = ‘R’INFO – [out]
INFO is INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value