kelvin_kei0
Evaluates the Kelvin function of the second kind, kei, of order zero.
Synopsis
#include <imsl.h>
float imsl_f_kelvin_kei0 (float x)
The type double function is imsl_d_kelvin_kei0.
Required Arguments
float x (Input)
Argument for which the function value is desired.
Return Value
The Kelvin function of the second kind, kei, of order zero evaluated at x.
Description
The modified Kelvin function kei0(x) is defined to be ℑK0(xeπ/4). The Bessel function K0(x) is defined
The function imsl_f_kelvin_kei0 is based on the work of Burgoyne (1963). If x < 0, NaN (Not a Number) is returned. If x ≥ 119, zero is returned.
Example
In this example, kei0(0.4) is evaluated.
#include <imsl.h>
#include <stdio.h>
int main()
{
float x = 0.4;
float ans;
x = imsl_f_kelvin_kei0 (x);
printf ("kei0(0.4) = %f\n", x);
}
Output
kei0(0.4) = -0.703800
