(C|Z)UNGHR¶

Single complex and double complex UNGHR.

Description¶

Generates a unitary matrix given a set of elementary reflectors and scale factors.

$Q = H_{ILO} \mult H_{ILO+1} \mult \dots \mult H_{IHI-1}$

The elementary reflectors and scale factors are expected in the same form as generated by GEHRD.

LAPACK Interface¶

void cunghr(const qml_long *N, const qml_long *ILO, const qml_long *IHI,
    qml_single_complex *A, const qml_long *LDA, qml_single_complex *TAU,
    qml_single_complex *WORK, const qml_long *LWORK, qml_long *INFO);

void zunghr(const qml_long *N, const qml_long *ILO, const qml_long *IHI,
    qml_double_complex *A, const qml_long *LDA, qml_double_complex *TAU,
    qml_double_complex *WORK, const qml_long *LWORK, qml_long *INFO);

Arguments¶

N	Number of rows and columns of A
ILO	Lower index
IHI	Upper index, 1 <= ILO <= IHI <= N
A	Elementary reflector vectors, overwritten with Q on exit
LDA	Leading dimension of A
TAU	Array of scale factors for reflectors
WORK	Work space of size at least LWORK
LWORK	Size of work space (-1 to query)
INFO	0 on success