#include <math.h>

#include <stdio.h>

#include <stdlib.h>

#include "globals.h"

#include "struct.h"

#define pi 3.141592653589793238

#define PI 3.1415926

#define C 0.569504e-12

#define LIM 3.0e-11

double EllipticF(double x, double K, double NP)

{

double _ellipticf_(),GaussLegendreInt(),af;

void w_f_ptr(),clear_struct();

Function X;

clear_struct(&X,2);

w_f_ptr(&X,_ellipticf_);

X.par[0].low_v = 0.0;

X.par[0].high_v = x;

X.par[1].val = K;

af = GaussLegendreInt(&X,0,(int) NP);

// printf("%lf\n",af);

return af;

}

double _ellipticf_(Function *X)

{

double r_pval(),p1,p2,af;

p1 = r_pval(X,0);

p2 = r_pval(X,1);

{

/**** Your code starts here ****/

double k,theta;

k=p2;

theta=p1;

af= 1.0/(sqrt(1-pow(k*sin(theta),2.0)));

// printf("k=%lf theta=%lg af=%lg\n",k,theta,af);

return af;

/**** Your code ends here****/

}

}