LAPACK
3.6.1
LAPACK: Linear Algebra PACKage
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subroutine sopgtr | ( | character | UPLO, |
integer | N, | ||
real, dimension( * ) | AP, | ||
real, dimension( * ) | TAU, | ||
real, dimension( ldq, * ) | Q, | ||
integer | LDQ, | ||
real, dimension( * ) | WORK, | ||
integer | INFO | ||
) |
SOPGTR
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SOPGTR 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 SSPTRD 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).
[in] | UPLO | 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. |
[in] | N | N is INTEGER The order of the matrix Q. N >= 0. |
[in] | AP | AP is REAL array, dimension (N*(N+1)/2) The vectors which define the elementary reflectors, as returned by SSPTRD. |
[in] | TAU | TAU is REAL array, dimension (N-1) TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by SSPTRD. |
[out] | Q | Q is REAL array, dimension (LDQ,N) The N-by-N orthogonal matrix Q. |
[in] | LDQ | LDQ is INTEGER The leading dimension of the array Q. LDQ >= max(1,N). |
[out] | WORK | WORK is REAL array, dimension (N-1) |
[out] | INFO | INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value |
Definition at line 116 of file sopgtr.f.