Contents
zung2r - generate an m by n complex matrix Q with orthonor-
mal columns,
SUBROUTINE ZUNG2R(M, N, K, A, LDA, TAU, WORK, INFO)
DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER M, N, K, LDA, INFO
SUBROUTINE ZUNG2R_64(M, N, K, A, LDA, TAU, WORK, INFO)
DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*)
INTEGER*8 M, N, K, LDA, INFO
F95 INTERFACE
SUBROUTINE UNG2R(M, [N], [K], A, [LDA], TAU, [WORK], [INFO])
COMPLEX(8), DIMENSION(:) :: TAU, WORK
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER :: M, N, K, LDA, INFO
SUBROUTINE UNG2R_64(M, [N], [K], A, [LDA], TAU, [WORK], [INFO])
COMPLEX(8), DIMENSION(:) :: TAU, WORK
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER(8) :: M, N, K, LDA, INFO
C INTERFACE
#include <sunperf.h>
void zung2r(int m, int n, int k, doublecomplex *a, int lda,
doublecomplex *tau, int *info);
void zung2r_64(long m, long n, long k, doublecomplex *a,
long lda, doublecomplex *tau, long *info);
zung2r R generates an m by n complex matrix Q with orthonor-
mal columns, which is defined as the first n columns of a
product of k elementary reflectors of order m
Q = H(1) H(2) . . . H(k)
as returned by CGEQRF.
M (input) The number of rows of the matrix Q. M >= 0.
N (input) The number of columns of the matrix Q. M >= N >=
0.
K (input) The number of elementary reflectors whose product
defines the matrix Q. N >= K >= 0.
A (input/output)
On entry, the i-th column must contain the vector
which defines the elementary reflector H(i), for i
= 1,2,...,k, as returned by CGEQRF in the first k
columns of its array argument A. On exit, the m
by n matrix Q.
LDA (input)
The first dimension of the array A. LDA >=
max(1,M).
TAU (input)
TAU(i) must contain the scalar factor of the ele-
mentary reflector H(i), as returned by CGEQRF.
WORK (workspace)
dimension(N)
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an ille-
gal value