naginterfaces.library.blas.dlhous

naginterfaces.library.blas.dlhous(z, z1, alpha, x)[source]

dlhous applies a LINPACK (as opposed to NAG) style real elementary reflection to a real vector.

For full information please refer to the NAG Library document for f06fu

https://www.nag.com/numeric/nl/nagdoc_28.5/flhtml/f06/f06fuf.html

Parameters
zfloat, array-like, shape

The vector , as returned by dlhousg().

z1float

The scalar , as returned by dlhousg().

If , is assumed to be the unit matrix and the transformation is skipped.

alphafloat

The original scalar .

xfloat, array-like, shape

The original vector .

Returns
alphafloat

The transformed scalar .

xfloat, ndarray, shape

The transformed vector .

Notes

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

dlhous applies a real elementary reflection (Householder matrix) , as generated by dlhousg(), to a given real vector:

where is an -element real vector and a real scalar.