unghr#

cunghr

Functions

void cunghr(
    const INT  n,
    const INT  ilo,
    const INT  ihi,
          c64* A,
    const INT  lda,
    const c64* tau,
          c64* work,
    const INT  lwork,
          INT* info
);

void cunghr(const INT n, const INT ilo, const INT ihi, c64 *A, const INT lda, const c64 *tau, c64 *work, const INT lwork, INT *info)#

CUNGHR generates a complex unitary matrix Q which is defined as the product of ihi-ilo elementary reflectors of order N, as returned by CGEHRD:

Q = H(ilo) H(ilo+1) … H(ihi-1).

Parameters

in

n

The order of the matrix Q. n >= 0.

in

ilo

ilo and ihi must have the same values as in the previous call of CGEHRD. Q is equal to the unit matrix except in the submatrix Q(ilo+1:ihi, ilo+1:ihi). 0 <= ilo <= ihi <= n-1, if n > 0; ilo=0 and ihi=-1, if n=0. (0-based indexing)

in

ihi

See ilo. (0-based)

inout

A

On entry, the vectors which define the elementary reflectors, as returned by CGEHRD. On exit, the n-by-n unitary matrix Q. Dimension (lda, n).

in

lda

The leading dimension of A. lda >= max(1, n).

in

tau

tau(i) must contain the scalar factor of the elementary reflector H(i), as returned by CGEHRD. Dimension (n-1).

out

work

Workspace array, dimension (max(1, lwork)). On exit, if info = 0, work[0] returns the optimal lwork.

in

lwork

The dimension of work. lwork >= ihi-ilo. For optimum performance lwork >= (ihi-ilo)*NB. If lwork = -1, a workspace query is assumed.

out

info

= 0: successful exit
< 0: if info = -i, the i-th argument had an illegal value.

zunghr

Functions

void zunghr(
    const INT   n,
    const INT   ilo,
    const INT   ihi,
          c128* A,
    const INT   lda,
    const c128* tau,
          c128* work,
    const INT   lwork,
          INT*  info
);

void zunghr(const INT n, const INT ilo, const INT ihi, c128 *A, const INT lda, const c128 *tau, c128 *work, const INT lwork, INT *info)#

ZUNGHR generates a complex unitary matrix Q which is defined as the product of ihi-ilo elementary reflectors of order N, as returned by ZGEHRD:

Q = H(ilo) H(ilo+1) … H(ihi-1).

Parameters

in

n

The order of the matrix Q. n >= 0.

in

ilo

ilo and ihi must have the same values as in the previous call of ZGEHRD. Q is equal to the unit matrix except in the submatrix Q(ilo+1:ihi, ilo+1:ihi). 0 <= ilo <= ihi <= n-1, if n > 0; ilo=0 and ihi=-1, if n=0. (0-based indexing)

in

ihi

See ilo. (0-based)

inout

A

On entry, the vectors which define the elementary reflectors, as returned by ZGEHRD. On exit, the n-by-n unitary matrix Q. Dimension (lda, n).

in

lda

The leading dimension of A. lda >= max(1, n).

in

tau

tau(i) must contain the scalar factor of the elementary reflector H(i), as returned by ZGEHRD. Dimension (n-1).

out

work

Workspace array, dimension (max(1, lwork)). On exit, if info = 0, work[0] returns the optimal lwork.

in

lwork

The dimension of work. lwork >= ihi-ilo. For optimum performance lwork >= (ihi-ilo)*NB. If lwork = -1, a workspace query is assumed.

out

info

= 0: successful exit
< 0: if info = -i, the i-th argument had an illegal value.

unghr#

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