?ormql
?ormql
Multiplies a real matrix by the orthogonal matrix Q of the QL factorization formed by
?geqlf
.Syntax
lapack_int
LAPACKE_sormql
(
int
matrix_layout
,
char
side
,
char
trans
,
lapack_int
m
,
lapack_int
n
,
lapack_int
k
,
const
float
*
a
,
lapack_int
lda
,
const
float
*
tau
,
float
*
c
,
lapack_int
ldc
);
lapack_int
LAPACKE_dormql
(
int
matrix_layout
,
char
side
,
char
trans
,
lapack_int
m
,
lapack_int
n
,
lapack_int
k
,
const
double
*
a
,
lapack_int
lda
,
const
double
*
tau
,
double
*
c
,
lapack_int
ldc
);
Include Files
- mkl.h
Description
The routine multiplies a real , where
m
-by-n
matrix C
by Q
or Q
T
Q
is the orthogonal matrix Q
of the QL
factorization formed by the routine geqlf. Depending on the parameters , *, , or (overwriting the result over
side
and trans
, the routine ormql can form one of the matrix products Q
*C
Q
T
C
C
*Q
C
*Q
T
C
).Input Parameters
- matrix_layout
- Specifies whether matrix storage layout is row major (LAPACK_ROW_MAJOR) or column major (LAPACK_COL_MAJOR).
- side
- Must be either'L'or'R'.If,side='L'QorQis applied toTCfrom the left.If,side='R'QorQis applied toTCfrom the right.
- trans
- Must be either'N'or'T'.If, the routine multipliestrans='N'CbyQ.If, the routine multipliestrans='T'CbyQ.T
- m
- The number of rows in the matrixC().m≥0
- n
- The number of columns inC().n≥0
- k
- The number of elementary reflectors whose product defines the matrixQ. Constraints:0if≤k≤m;side='L'0if≤k≤n.side='R'
- a,tau,c
- Arrays:a,tau,c.The size ofamust be:For column major layout regardless ofside, max(1,lda*k).Forside= 'L' and row major layout, max(1,lda*m).Forside= 'R' and row major layout, max(1,lda*n).On entry, theith column ofamust contain the vector which defines the elementary reflectorH, for i = 1,2,...,ik, as returned bysgeqlf/dgeqlfin the lastkcolumns of its array argumenta.must contain the scalar factor of the elementary reflectortau[i- 1]H, as returned byisgeqlf/dgeqlf.The size oftaumust be at least max(1,k).c(size max(1,contains theldc*n) for column major layout and max(1,ldc*m) for row major layout)m-by-nmatrixC.
- lda
- The leading dimension ofa;if,side='L'lda≥max(1,m)for column major layout and max(1,;k) for row major layoutif,side='R'lda≥max(1,n)for column major layout and max(1,.k) for row major layout
- ldc
- The leading dimension ofc;ldc≥max(1,m)for column major layout and max(1,.n) for row major layout
Output Parameters
- c
- Overwritten by the product,Q*C,Q*TC, orC*Q(as specified byC*QTsideandtrans).
Return Values
This function returns a value
info
.If , the execution is successful.
info
=0If , the
info
= -i
i
-th parameter had an illegal value.Application Notes
The complex counterpart of this routine is unmql.