?syr
?syr
Performs the symmetric rank-1 update of a complex symmetric matrix.
Syntax
lapack_int
LAPACKE_csyr
(
int
matrix_layout
,
char
uplo
,
lapack_int
n
,
lapack_complex_float
alpha
,
const
lapack_complex_float
*
x
,
lapack_int
incx
,
lapack_complex_float
*
a
,
lapack_int
lda
);
lapack_int
LAPACKE_zsyr
(
int
matrix_layout
,
char
uplo
,
lapack_int
n
,
lapack_complex_double
alpha
,
const
lapack_complex_double
*
x
,
lapack_int
incx
,
lapack_complex_double
*
a
,
lapack_int
lda
);
Include Files
- mkl.h
Description
The routine performs the symmetric rank 1 operation defined as
a
:= alpha
*x
*x
H
a
where:
- alphais a complex scalar.
- xis ann-element complex vector.
- ais ann-by-ncomplex symmetric matrix.
These routines have their real equivalents in BLAS (see
?syr
in Chapter "BLAS and Sparse BLAS Routines"
).Input Parameters
- matrix_layout
- Specifies whether matrix storage layout is row major (LAPACK_ROW_MAJOR) or column major (LAPACK_COL_MAJOR).
- uplo
- Specifies whether the upper or lower triangular part of the arrayais used:Iforuplo='U''u', then the upper triangular part of the arrayais used.Iforuplo='L''l', then the lower triangular part of the arrayais used.
- n
- Specifies the order of the matrixa. The value ofnmust be at least zero.
- alpha
- Specifies the scalaralpha.
- x
- Array, size at least(1 + (. Before entry, the incremented arrayn- 1)*abs(incx))xmust contain then-element vectorx.
- incx
- Specifies the increment for the elements ofx. The value ofincxmust not be zero.
- a
- Array, sizemax(1,. Before entry withlda*n)oruplo='U''u', the leadingn-by-nupper triangular part of the arrayamust contain the upper triangular part of the symmetric matrix and the strictly lower triangular part ofais not referenced.Before entry withoruplo='L''l', the leadingn-by-nlower triangular part of the arrayamust contain the lower triangular part of the symmetric matrix and the strictly upper triangular part ofais not referenced.
- lda
- Specifies the leading dimension ofaas declared in the calling (sub)program. The value ofldamust be at least.max(1,n)
Output Parameters
- a
- Withoruplo='U''u', the upper triangular part of the arrayais overwritten by the upper triangular part of the updated matrix.Withoruplo='L''l', the lower triangular part of the arrayais overwritten by the lower triangular part of the updated matrix.
Return Values
This function returns a value
info
.If , the execution is successful.
info
= 0If
, the info
< 0i
-th parameter had an illegal value.If
, memory allocation error occurred.info
= -1011