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template<typename T>
void orglq(integer *m, integer *n, integer *k, T *a, integer *lda, T *tau, T *work, integer *lwork, integer *info)# Form Q from LQ factorization.
Purpose:
Generate an m-by-n real matrix Q with orthonormal rows, which is defined as the first M rows of a product of K elementary reflectors of order N Q = H(k) . . . H(2) H(1) as returned by SGELQF.
- Parameters:
m – [in]
m is integer*
The number of rows of the matrix Q. m >= 0.
n – [in]
n is integer*
The number of columns of the matrix Q. n >= m.
k – [in]
k is integer*
The number of elementary reflectors whose product defines the matrix Q. m >= k >= 0.
a – [inout]
a is float/doublearray, dimension (lda,n)
On entry, the i-th row must contain the vector which defines the elementary reflector H(i), for i = 1,2,…,k, as returned by SGELQF in the first k rows of its array argument a. On exit, the m-by-n matrix Q.
lda – [in]
lda is integer*
The first dimension of the array a. lda >= fla_max(1,m).
tau – [in]
tau is float/double array, dimension (k)
tau(i) must contain the scalar factor of the elementary reflector H(i), as returned by SGELQF.
WORK – [out]
WORK is REAL array, dimension (MAX(1,LWORK))
On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
LWORK – [in]
LWORK is INTEGER
The dimension of the array WORK. LWORK >= fla_max(1,M). For optimum performance LWORK >= M*NB, where NB is the optimal blocksize.
If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.INFO – [out]
INFO is INTEGER
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an illegal value