3.5.2.5.14 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.