naginterfaces.library.blas.dsymv¶
- naginterfaces.library.blas.dsymv(uplo, alpha, a, x, beta, y=None)[source]¶
dsymv
the matrix-vector product for a real symmetric matrix.For full information please refer to the NAG Library document for f06pc
https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/f06/f06pcf.html
- Parameters
- uplostr, length 1
Specifies whether the upper or lower triangular part of is stored.
The upper triangular part of is stored.
The lower triangular part of is stored.
- alphafloat
The scalar .
- afloat, array-like, shape
The symmetric matrix .
- xfloat, array-like, shape
The -element vector .
- betafloat
The scalar .
- yNone or float, array-like, shape , optional
The -element vector , if need not be set.
- Returns
- yfloat, ndarray, shape
The updated vector .
- Raises
- NagValueError
- (errno )
On entry, error in parameter .
Constraint: or .
- (errno )
On entry, error in parameter .
Constraint: .
- (errno )
On entry, error in parameter .
Constraint: .
- (errno )
On entry, error in parameter .
Constraint: .
- Notes
In the NAG Library the traditional C interface for this routine uses a different algorithmic base. Please contact NAG if you have any questions about compatibility.
dsymv
performs the matrix-vector operationwhere is an real symmetric matrix, and are -element real vectors, and and are real scalars.