# naginterfaces.library.blas.zhpr¶

naginterfaces.library.blas.zhpr(uplo, alpha, x, ap)[source]

zhpr computes the rank-1 update of a complex Hermitian matrix stored in packed form.

For full information please refer to the NAG Library document for f06sq

https://www.nag.com/numeric/nl/nagdoc_28.7/flhtml/f06/f06sqf.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 .

xcomplex, array-like, shape

The -element vector .

apcomplex, array-like, shape

The Hermitian matrix , packed by columns.

Returns
apcomplex, ndarray, shape

The updated matrix . The imaginary parts of the diagonal elements are set to zero.

Raises
NagValueError
(errno )

On entry, error in parameter .

Constraint: or .

(errno )

On entry, error in parameter .

Constraint: .

(errno )

On entry, error in parameter .

Constraint: .

Notes

zhpr performs the Hermitian rank-1 update operation

where is an complex Hermitian matrix, stored in packed form, is an -element complex vector, and is a real scalar.