# naginterfaces.library.specfun.bessel_​k1_​scaled_​vector¶

naginterfaces.library.specfun.bessel_k1_scaled_vector(x)[source]

bessel_k1_scaled_vector returns an array of values of the scaled modified Bessel function .

For full information please refer to the NAG Library document for s18cr

https://www.nag.com/numeric/nl/nagdoc_28.5/flhtml/s/s18crf.html

Parameters
xfloat, array-like, shape

The argument of the function, for .

Returns
ffloat, ndarray, shape

, the function values.

ivalidint, ndarray, shape

contains the error code for , for .

No error.

On entry, , is undefined. contains .

is too close to zero, as determined by the value of the safe-range parameter machine.real_safe: there is a danger of causing overflow. contains the reciprocal of the safe-range parameter.

Raises
NagValueError
(errno )

On entry, .

Constraint: .

Warns
NagAlgorithmicWarning
(errno )

On entry, at least one value of was invalid.

bessel_k1_scaled_vector evaluates an approximation to , where is a modified Bessel function of the second kind for an array of arguments , for . The scaling factor removes most of the variation in .
The function uses the same Chebyshev expansions as bessel_k1_real_vector(), which returns an array of the unscaled values of .