naginterfaces.library.blas.dlantr¶
- naginterfaces.library.blas.dlantr(norm, uplo, diag, m, a)[source]¶
dlantr
returns the value of the -norm, the -norm, the Frobenius norm, or the maximum absolute value of the elements of a real trapezoidal matrix (triangular if ).For full information please refer to the NAG Library document for f06rj
https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/f06/f06rjf.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 trapezoidal.
is upper trapezoidal.
is lower trapezoidal.
- 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.
- mint
, the number of rows of the matrix .
When ,
dlantr
is set to zero.- afloat, array-like, shape
The trapezoidal matrix .
- Returns
- nrmfloat
The value of the -norm, the -norm, the Frobenius norm, or the maximum absolute value of the elements of the real trapezoidal matrix (triangular if ).
- 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.