/* Driver for routine ftest */

#include <stdio.h>
#include <math.h>
#include "nr.h"
#include "nrutil.h"

#define NPTS 1000
#define MPTS 500
#define EPS 0.01
#define NVAL 11

main()
{
	long idum=(-13);
	int i,j;
	float f,factor,prob,vrnce,*data1,*data2,*data3;

	data1=vector(1,NPTS);
	data2=vector(1,MPTS);
	data3=vector(1,MPTS);
	/* Generate two gaussian distributions with different variances */
	printf("\n%16s %5.2f\n","Variance 1 = ",1.0);
	printf("%13s %11s %16s\n","Variance 2","Ratio","Probability");
	for (j=1;j<=NPTS;j++) data1[j]=gasdev(&idum);
	for (j=1;j<=MPTS;j++) data2[j]=gasdev(&idum);
	for (i=1;i<=NVAL;i++) {
		vrnce=1.0+(i-1)*EPS;
		factor=sqrt(vrnce);
		for (j=1;j<=MPTS;j++) data3[j]=factor*data2[j];
		ftest(data1,NPTS,data3,MPTS,&f,&prob);
		printf("%11.4f %13.4f %13.4f\n",vrnce,f,prob);
	}
	free_vector(data3,1,MPTS);
	free_vector(data2,1,MPTS);
	free_vector(data1,1,NPTS);
	return 0;
}