dopmtr()

subroutine dopmtr	(	character	side,
		character	uplo,
		character	trans,
		integer	m,
		integer	n,
		double precision, dimension( * )	ap,
		double precision, dimension( * )	tau,
		double precision, dimension( ldc, * )	c,
		integer	ldc,
		double precision, dimension( * )	work,
		integer	info )

DOPMTR

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Purpose:

!>
!> DOPMTR 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 DSPTRD 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

[in]	SIDE	!> SIDE is CHARACTER*1 !> = 'L': apply Q or Q**T from the Left; !> = 'R': apply Q or Q**T from the Right. !>
[in]	UPLO	!> UPLO is CHARACTER*1 !> = 'U': Upper triangular packed storage used in previous !> call to DSPTRD; !> = 'L': Lower triangular packed storage used in previous !> call to DSPTRD. !>
[in]	TRANS	!> TRANS is CHARACTER*1 !> = 'N': No transpose, apply Q; !> = 'T': Transpose, apply Q**T. !>
[in]	M	!> M is INTEGER !> The number of rows of the matrix C. M >= 0. !>
[in]	N	!> N is INTEGER !> The number of columns of the matrix C. N >= 0. !>
[in]	AP	!> AP is DOUBLE PRECISION 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 DSPTRD. AP is modified by the routine but !> restored on exit. !>
[in]	TAU	!> TAU is DOUBLE PRECISION 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 DSPTRD. !>
[in,out]	C	!> C is DOUBLE PRECISION 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. !>
[in]	LDC	!> LDC is INTEGER !> The leading dimension of the array C. LDC >= max(1,M). !>
[out]	WORK	!> WORK is DOUBLE PRECISION array, dimension !> (N) if SIDE = 'L' !> (M) if SIDE = 'R' !>
[out]	INFO	!> INFO is INTEGER !> = 0: successful exit !> < 0: if INFO = -i, the i-th argument had an illegal value !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.