dopgtr.f3

!>
!> DOPGTR generates a real orthogonal matrix Q which is defined as the
!> product of n-1 elementary reflectors H(i) of order n, as returned by
!> DSPTRD using packed storage:
!>
!> if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),
!>
!> if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).
!> 

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.
!> 

N

!>          N is INTEGER
!>          The order of the matrix Q. N >= 0.
!> 

AP

!>          AP is DOUBLE PRECISION array, dimension (N*(N+1)/2)
!>          The vectors which define the elementary reflectors, as
!>          returned by DSPTRD.
!> 

TAU

!>          TAU is DOUBLE PRECISION array, dimension (N-1)
!>          TAU(i) must contain the scalar factor of the elementary
!>          reflector H(i), as returned by DSPTRD.
!> 

Q

!>          Q is DOUBLE PRECISION array, dimension (LDQ,N)
!>          The N-by-N orthogonal matrix Q.
!> 

LDQ

!>          LDQ is INTEGER
!>          The leading dimension of the array Q. LDQ >= max(1,N).
!> 

WORK

!>          WORK is DOUBLE PRECISION array, dimension (N-1)
!> 

INFO

!>          INFO is INTEGER
!>          = 0:  successful exit
!>          < 0:  if INFO = -i, the i-th argument had an illegal value
!> 

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