/******************************************
 *
 *   Cedric Pradalier   2001
 *   mail : http://cedric.pradalier.free.fr/mail.html  
 *
 *****************************************/

#include <stdlib.h>
#include <stdio.h>
#include "linreg.h"

#define N 100
int main()
{
    int i;
    double x[N];
    double y[N];
    double a,b,r2,p;
    FILE * fp;
    fp = fopen("data","w");

    for (i=0;i<N;i++)
    {
        p = 2*drand48() - 1;
        x[i]=drand48();
        
        y[i]=x[i] + 1 + 0.1*p;
        if (fp!=NULL) fprintf(fp,"%e\t%e\n",x[i],y[i]);
    }
    if (fp!=NULL) fclose(fp);
    
    linreg(N,x,y,&b,&a,&r2);

    printf("y = %f * x + %f with a precision of %f\n",a,b,r2);
    return 0;

}