zupgtr - generate a complex unitary matrix Q which is defined as the product of n-1 elementary reflectors H(i)
of order n, as returned by CHPTRD using packed storage
SUBROUTINE ZUPGTR( UPLO, N, AP, TAU, Q, LDQ, WORK, INFO) CHARACTER * 1 UPLO DOUBLE COMPLEX AP(*), TAU(*), Q(LDQ,*), WORK(*) INTEGER N, LDQ, INFO
SUBROUTINE ZUPGTR_64( UPLO, N, AP, TAU, Q, LDQ, WORK, INFO) CHARACTER * 1 UPLO DOUBLE COMPLEX AP(*), TAU(*), Q(LDQ,*), WORK(*) INTEGER*8 N, LDQ, INFO
SUBROUTINE UPGTR( UPLO, [N], AP, TAU, Q, [LDQ], [WORK], [INFO]) CHARACTER(LEN=1) :: UPLO COMPLEX(8), DIMENSION(:) :: AP, TAU, WORK COMPLEX(8), DIMENSION(:,:) :: Q INTEGER :: N, LDQ, INFO
SUBROUTINE UPGTR_64( UPLO, [N], AP, TAU, Q, [LDQ], [WORK], [INFO]) CHARACTER(LEN=1) :: UPLO COMPLEX(8), DIMENSION(:) :: AP, TAU, WORK COMPLEX(8), DIMENSION(:,:) :: Q INTEGER(8) :: N, LDQ, INFO
#include <sunperf.h>
void zupgtr(char uplo, int n, doublecomplex *ap, doublecomplex *tau, doublecomplex *q, int ldq, int *info);
void zupgtr_64(char uplo, long n, doublecomplex *ap, doublecomplex *tau, doublecomplex *q, long ldq, long *info);
zupgtr generates a complex unitary matrix Q which is defined as the
product of n-1 elementary reflectors H(i)
of order n, as returned by
CHPTRD using packed storage:
if UPLO = 'U', Q = H(n-1)
. . . H(2)
H(1),
if UPLO = 'L', Q = H(1)
H(2)
. . . H(n-1).
= 'U': Upper triangular packed storage used in previous call to CHPTRD; = 'L': Lower triangular packed storage used in previous call to CHPTRD.
TAU(i)
must contain the scalar factor of the elementary
reflector H(i), as returned by CHPTRD.
dimension(N-1)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value