naginterfaces.library.blas.dtpsv¶
- naginterfaces.library.blas.dtpsv(uplo, trans, diag, ap, x)[source]¶
dtpsv
solves a real triangular system of equations, stored in packed form, with a single right-hand side.For full information please refer to the NAG Library document for f06pl
https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/f06/f06plf.html
- Parameters
- uplostr, length 1
Specifies whether is upper or lower triangular.
is upper triangular.
is lower triangular.
- transstr, length 1
Specifies the operation to be performed.
.
or
.
- diagstr, length 1
Specifies whether has nonunit or unit diagonal elements.
The diagonal elements are stored explicitly.
The diagonal elements are assumed to be , and are not referenced.
- apfloat, array-like, shape
The triangular matrix , packed by columns.
- xfloat, array-like, shape
The -element vector .
- Returns
- xfloat, ndarray, shape
The updated vector .
- Raises
- NagValueError
- (errno )
On entry, error in parameter .
Constraint: or .
- (errno )
On entry, error in parameter .
Constraint: , or .
- (errno )
On entry, error in parameter .
Constraint: or .
- (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.
dtpsv
performs one of the matrix-vector operationswhere is an real triangular matrix, stored in packed form, and is an -element real vector. denotes or equivalently .
No test for singularity or near-singularity of is included in this function. Such tests must be performed before calling this function.