naginterfaces.library.blas.dspr2¶
- naginterfaces.library.blas.dspr2(uplo, alpha, x, y, ap)[source]¶
dspr2
computes the rank-2 update of a real symmetric matrix stored in packed form.For full information please refer to the NAG Library document for f06ps
https://support.nag.com/numeric/nl/nagdoc_30.1/flhtml/f06/f06psf.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 .
- xfloat, array-like, shape
The -element vector .
- yfloat, array-like, shape
The -element vector .
- apfloat, array-like, shape
The symmetric matrix , packed by columns.
- Returns
- apfloat, ndarray, shape
The updated matrix .
- 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.
dspr2
performs the symmetric rank-2 update operationwhere is an real symmetric matrix, stored in packed form, and are -element real vectors, and is a real scalar.