naginterfaces.library.blas.drotj

naginterfaces.library.blas.drotj(job, x, y, z)[source]

drotj generates a real Jacobi plane rotation.

For full information please refer to the NAG Library document for f06be

https://www.nag.com/numeric/nl/nagdoc_28.7/flhtml/f06/f06bef.html

Parameters
jobstr, length 1

Specifies the property which determines the precise form of the rotation.

.

.

.

xfloat

The value , the element of the input matrix.

yfloat

The value , the or element of the input matrix.

zfloat

The value . the element of the input matrix.

Returns
xfloat

The value .

yfloat

The value , the tangent of the rotation.

zfloat

The value .

cfloat

The value , the cosine of the rotation.

sfloat

The value , the sine of the rotation.

Raises
NagValueError
(errno )

On entry, error in parameter .

Constraint: , or .

Notes

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

drotj generates a real Jacobi plane rotation with parameters and , which diagonalizes a given real symmetric matrix: