naginterfaces.library.blas.dscal

naginterfaces.library.blas.dscal(alpha, x)

dscal multiplies a real vector by a real scalar.

For full information please refer to the NAG Library document for f06ed

https://support.nag.com/numeric/nl/nagdoc_30.2/flhtml/f06/f06edf.html

Parameters

alphafloat

The scalar $\alpha$.

xfloat, ndarray, shape $\left(n\right)$, modified in place

On entry: the $n$-element vector $x$.

On exit: the vector $\alpha x$.

Raises

NagValueError

(errno $4$)

On entry, error in parameter $\text{incx}$.

Constraint: $\text{incx}>0$.

Notes

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

dscal performs the operation

$$x\leftarrow \alpha x$$

where $x$ is an $n$-element real vector, and $\alpha$ is a real scalar.

References

Lawson, C L, Hanson, R J, Kincaid, D R and Krogh, F T, 1979, Basic linear algebra supbrograms for Fortran usage, ACM Trans. Math. Software (5), 308–325