Evaluates the complete elliptic integral of the kind K(x).

Synopsis

#include <imsl.h>

float imsl_f_elliptic_integral_K (float x)

The type double function is imsl_d_elliptic_integral_K.

Required Arguments

float x   (Input)
Argument for which the function value is desired.

Return Value

The complete elliptic integral K(x).

Description

The complete elliptic integral of the first kind is defined to be

The argument x must satisfy 0 £ x < 1; otherwise, imsl_f_elliptic_integral_K re­turns imsl_f_machine(2), the largest representable floating-point number.

The function K(x) is computed using the routine imsl_f_elliptic_integral_RF and the relation K(x) = RF(0, 1 - x, 1).

Example

The integral K(0) is evaluated.

#include <imsl.h>

main()

{

        float   x = 0.0;

        float   ans;

        x = imsl_f_elliptic_integral_K (x);

        printf ("K(0.0) = %f\n", x);

}

Output

K(0.0) = 1.570796

Visual Numerics, Inc. Visual Numerics - Developers of IMSL and PV-WAVE http://www.vni.com/ PHONE: 713.784.3131 FAX:713.781.9260