# naginterfaces.library.blas.zlantb¶

naginterfaces.library.blas.zlantb(norm, uplo, diag, k, ab)[source]

zlantb returns the value of the -norm, the -norm, the Frobenius norm, or the maximum absolute value of the elements of a complex triangular band matrix.

For full information please refer to the NAG Library document for f06ul

https://www.nag.com/numeric/nl/nagdoc_28.7/flhtml/f06/f06ulf.html

Parameters
normstr, length 1

Specifies the value to be returned.

or

The -norm.

The -norm.

or

The Frobenius (or Euclidean) norm.

The value (not a norm).

uplostr, length 1

Specifies whether is upper or lower triangular.

is upper triangular.

is lower triangular.

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.

kint

, the number of subdiagonals or superdiagonals of the matrix .

abcomplex, array-like, shape

The triangular band matrix

Returns
nrmfloat

The value of the -norm, the -norm, the Frobenius norm, or the maximum absolute value of the elements of the complex triangular band matrix.

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

No equivalent traditional C interface for this routine exists in the NAG Library.