#include <math.h>

#include "nr.h"

void usrfun(double *x,int n,double *fvec,double **fjac)
{

	int i;

	fjac[0][0] = -2.0*x[0];
	fjac[0][1] = -2.0*x[1];
	fjac[0][2] = -2.0*x[2];
	fjac[0][3]=1.0;
	for (i=0;i<n;i++) fjac[1][i]=2.0*x[i];
	fjac[2][0]=1.0;
	fjac[2][1] = -1.0;
	fjac[2][2]=0.0;
	fjac[2][3]=0.0;
	fjac[3][0]=0.0;
	fjac[3][1]=1.0;
	fjac[3][2] = -1.0;
	fjac[3][3]=0.0;
	fvec[0] = -SQR(x[0])-SQR(x[1])-SQR(x[2])+x[3];
	fvec[1]=SQR(x[0])+SQR(x[1])+SQR(x[2])+SQR(x[3])-1.0;
	fvec[2]=x[0]-x[1];
	fvec[3]=x[1]-x[2];

}