dopgtr.f man page
subroutine dopgtr (UPLO, N, AP, TAU, Q, LDQ, WORK, INFO)
subroutine dopgtr (character UPLO, integer N, double precision, dimension( * ) AP, double precision, dimension( * ) TAU, double precision, dimension( ldq, * ) Q, integer LDQ, double precision, dimension( * ) WORK, integer INFO)
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 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 is INTEGER The order of the matrix Q. N >= 0.
AP is DOUBLE PRECISION array, dimension (N*(N+1)/2) The vectors which define the elementary reflectors, as returned by DSPTRD.
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 is DOUBLE PRECISION array, dimension (LDQ,N) The N-by-N orthogonal matrix Q.
LDQ is INTEGER The leading dimension of the array Q. LDQ >= max(1,N).
WORK is DOUBLE PRECISION array, dimension (N-1)
INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
Definition at line 116 of file dopgtr.f.
Generated automatically by Doxygen for LAPACK from the source code.
The man page dopgtr(3) is an alias of dopgtr.f(3).