cungql - generate an M-by-N complex matrix Q with orthonormal columns,
SUBROUTINE CUNGQL( M, N, K, A, LDA, TAU, WORK, LWORK, INFO) COMPLEX A(LDA,*), TAU(*), WORK(*) INTEGER M, N, K, LDA, LWORK, INFO
SUBROUTINE CUNGQL_64( M, N, K, A, LDA, TAU, WORK, LWORK, INFO) COMPLEX A(LDA,*), TAU(*), WORK(*) INTEGER*8 M, N, K, LDA, LWORK, INFO
SUBROUTINE UNGQL( M, [N], [K], A, [LDA], TAU, [WORK], [LWORK], [INFO]) COMPLEX, DIMENSION(:) :: TAU, WORK COMPLEX, DIMENSION(:,:) :: A INTEGER :: M, N, K, LDA, LWORK, INFO
SUBROUTINE UNGQL_64( M, [N], [K], A, [LDA], TAU, [WORK], [LWORK], * [INFO]) COMPLEX, DIMENSION(:) :: TAU, WORK COMPLEX, DIMENSION(:,:) :: A INTEGER(8) :: M, N, K, LDA, LWORK, INFO
#include <sunperf.h>
void cungql(int m, int n, int k, complex *a, int lda, complex *tau, int *info);
void cungql_64(long m, long n, long k, complex *a, long lda, complex *tau, long *info);
cungql generates an M-by-N complex matrix Q with orthonormal columns, which is defined as the last N columns of a product of K elementary reflectors of order M
Q = H(k) . . . H(2) H(1)
as returned by CGEQLF.
TAU(i)
must contain the scalar factor of the elementary
reflector H(i), as returned by CGEQLF.
WORK(1)
returns the optimal LWORK.
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.
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an illegal value