zunghr (3p)

Name

zunghr - generate a complex unitary matrix Q which is defined as the product of IHI-ILO elementary reflectors of order N, as returned by ZGEHRD

Synopsis

SUBROUTINE ZUNGHR(N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO)

DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER N, ILO, IHI, LDA, LWORK, INFO

SUBROUTINE ZUNGHR_64(N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO)

DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER*8 N, ILO, IHI, LDA, LWORK, INFO




F95 INTERFACE
SUBROUTINE UNGHR(N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO)

COMPLEX(8), DIMENSION(:) :: TAU, WORK
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER :: N, ILO, IHI, LDA, LWORK, INFO

SUBROUTINE UNGHR_64(N, ILO, IHI, A, LDA, TAU, WORK, LWORK,
INFO)

COMPLEX(8), DIMENSION(:) :: TAU, WORK
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER(8) :: N, ILO, IHI, LDA, LWORK, INFO




C INTERFACE
#include <sunperf.h>

void zunghr(int n, int ilo, int ihi, doublecomplex *a, int lda, double-
complex *tau, int *info);

void zunghr_64(long n, long ilo, long ihi, doublecomplex *a, long  lda,
doublecomplex *tau, long *info);

Description

Oracle Solaris Studio Performance Library                           zunghr(3P)



NAME
       zunghr  -  generate  a complex unitary matrix Q which is defined as the
       product of IHI-ILO elementary reflectors of order  N,  as  returned  by
       ZGEHRD


SYNOPSIS
       SUBROUTINE ZUNGHR(N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO)

       DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
       INTEGER N, ILO, IHI, LDA, LWORK, INFO

       SUBROUTINE ZUNGHR_64(N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO)

       DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
       INTEGER*8 N, ILO, IHI, LDA, LWORK, INFO




   F95 INTERFACE
       SUBROUTINE UNGHR(N, ILO, IHI, A, LDA, TAU, WORK, LWORK, INFO)

       COMPLEX(8), DIMENSION(:) :: TAU, WORK
       COMPLEX(8), DIMENSION(:,:) :: A
       INTEGER :: N, ILO, IHI, LDA, LWORK, INFO

       SUBROUTINE UNGHR_64(N, ILO, IHI, A, LDA, TAU, WORK, LWORK,
              INFO)

       COMPLEX(8), DIMENSION(:) :: TAU, WORK
       COMPLEX(8), DIMENSION(:,:) :: A
       INTEGER(8) :: N, ILO, IHI, LDA, LWORK, INFO




   C INTERFACE
       #include <sunperf.h>

       void zunghr(int n, int ilo, int ihi, doublecomplex *a, int lda, double-
                 complex *tau, int *info);

       void zunghr_64(long n, long ilo, long ihi, doublecomplex *a, long  lda,
                 doublecomplex *tau, long *info);



PURPOSE
       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).


ARGUMENTS
       N (input) The order of the matrix Q. N >= 0.


       ILO (input)
                 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 subma-
                 trix Q(ilo+1:ihi,ilo+1:ihi).  1 <= ILO <= IHI <= N, if N > 0;
                 ILO=1 and IHI=0, if N=0.


       IHI (input)
                 See the description of IHI.


       A (input/output)
                 On entry, the vectors which define the elementary reflectors,
                 as returned by ZGEHRD.  On exit, the N-by-N unitary matrix Q.


       LDA (input)
                 The leading dimension of the array A. LDA >= max(1,N).


       TAU (input)
                 TAU(i) must contain  the  scalar  factor  of  the  elementary
                 reflector H(i), as returned by ZGEHRD.


       WORK (workspace)
                 On exit, if INFO = 0, WORK(1) returns the optimal LWORK.


       LWORK (input)
                 The dimension of the array WORK. LWORK >= IHI-ILO.  For opti-
                 mum performance LWORK >= (IHI-ILO)*NB, where NB is the  opti-
                 mal 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 (output)
                 = 0:  successful exit;
                 < 0:  if INFO = -i, the i-th argument had an illegal value.




                                  7 Nov 2015                        zunghr(3P)