dorgql
dorgql - generate an M-by-N real matrix Q with orthonormal columns,
SUBROUTINE DORGQL( M, N, K, A, LDA, TAU, WORK, LDWORK, INFO)
INTEGER M, N, K, LDA, LDWORK, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), WORK(*)
SUBROUTINE DORGQL_64( M, N, K, A, LDA, TAU, WORK, LDWORK, INFO)
INTEGER*8 M, N, K, LDA, LDWORK, INFO
DOUBLE PRECISION A(LDA,*), TAU(*), WORK(*)
SUBROUTINE ORGQL( M, [N], [K], A, [LDA], TAU, [WORK], [LDWORK],
* [INFO])
INTEGER :: M, N, K, LDA, LDWORK, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A
SUBROUTINE ORGQL_64( M, [N], [K], A, [LDA], TAU, [WORK], [LDWORK],
* [INFO])
INTEGER(8) :: M, N, K, LDA, LDWORK, INFO
REAL(8), DIMENSION(:) :: TAU, WORK
REAL(8), DIMENSION(:,:) :: A
#include <sunperf.h>
void dorgql(int m, int n, int k, double *a, int lda, double *tau, int *info);
void dorgql_64(long m, long n, long k, double *a, long lda, double *tau, long *info);
dorgql generates an M-by-N real matrix Q with orthonormal columns,
which is defined as the last N columns of a product of K elementary
reflectors of order M
Q = H(k) . . . H(2) H(1)
as returned by SGEQLF.
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* M (input)
-
The number of rows of the matrix Q. M >= 0.
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* N (input)
-
The number of columns of the matrix Q. M >= N >= 0.
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* K (input)
-
The number of elementary reflectors whose product defines the
matrix Q. N >= K >= 0.
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* A (input/output)
-
On entry, the (n-k+i)-th column must contain the vector which
defines the elementary reflector H(i), for i = 1,2,...,k, as
returned by SGEQLF in the last k columns of its array
argument A.
On exit, the M-by-N matrix Q.
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* LDA (input)
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The first dimension of the array A. LDA >= max(1,M).
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* TAU (input)
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TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by SGEQLF.
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* WORK (workspace)
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On exit, if INFO = 0, WORK(1) returns the optimal LDWORK.
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* LDWORK (input)
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The dimension of the array WORK. LDWORK >= max(1,N).
For optimum performance LDWORK >= N*NB, where NB is the
optimal blocksize.
If LDWORK = -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 LDWORK is issued by XERBLA.
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* INFO (output)
-