Contents
dorg2r - generate an m by n real matrix Q with orthonormal
columns,
SUBROUTINE DORG2R(M, N, K, A, LDA, TAU, WORK, INFO)
INTEGER M, N, K, LDA, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), WORK(*)
SUBROUTINE DORG2R_64(M, N, K, A, LDA, TAU, WORK, INFO)
INTEGER*8 M, N, K, LDA, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), WORK(*)
F95 INTERFACE
SUBROUTINE ORG2R([M], [N], [K], A, [LDA], TAU, [WORK], [INFO])
INTEGER :: M, N, K, LDA, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A
SUBROUTINE ORG2R_64([M], [N], [K], A, [LDA], TAU, [WORK], [INFO])
INTEGER(8) :: M, N, K, LDA, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A
C INTERFACE
#include <sunperf.h>
void dorg2r(int m, int n, int k, double *a, int lda, double
*tau, int *info);
void dorg2r_64(long m, long n, long k, double *a, long lda,
double *tau, long *info);
dorg2r R generates an m by n real matrix Q with orthonormal
columns, which is defined as the first n columns of a pro-
duct of k elementary reflectors of order m
Q = H(1) H(2) . . . H(k)
as returned by SGEQRF.
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 SGEQRF 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 SGEQRF.
WORK (workspace)
dimension(N)
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument has an ille-
gal value