# 3.5.1.3.14 Bessel_k_nu_scaled

## Definition:

$k\_nu\_scaled = bessel\_k\_nu\_scaled(x,nu)$ evaluates an approximation to the modified Bessel function of the second kind $e^{-x}K_{\upsilon /4}(x)$, where the order $\nu$ = -3, -2, -1, 1, 2 or 3 and x is real and positive. For negative orders the formula

     $K_{-\upsilon /4}(x)=K_{\upsilon /4}(x)$


is used.

For more information please review the s18edc function in the NAG document.

## Parameters:

x (input, double)
The argument x of the function.
Constraints:
     x>0.0.

$nu$ (input, int)
The argument $\nu$ of the function.
Constraints:
     $1\leq abs(nu)\leq 3$

$k\_nu\_scaled$ (output, double)
Approximation of the modified Bessel function of the second kind.