text: 
  /* Driver for routine medfit */
  
  #include <stdio.h>
  #define NRANSI
  #include "nr.h"
  #include "nrutil.h"
  
  #define NPT 100
  #define SPREAD 0.1
  #define NDATA NPT
  
  int main(void)
  {
  	long idum=(-1984);
  	int i,mwt=1;
  	float a,abdev,b,chi2,q,siga,sigb;
  	float *x,*y,*sig;
  
  	x=vector(1,NDATA);
  	y=vector(1,NDATA);
  	sig=vector(1,NDATA);
  	for (i=1;i<=NPT;i++) {
  		x[i]=0.1*i;
  		y[i] = -2.0*x[i]+1.0+SPREAD*gasdev(&idum);
  		sig[i]=SPREAD;
  	}
  	fit(x,y,NPT,sig,mwt,&a,&b,&siga,&sigb,&chi2,&q);
  	printf("\nAccording to routine FIT the result is:\n");
  	printf("   a =  %8.4f   uncertainty:  %8.4f\n",a,siga);
  	printf("   b =  %8.4f   uncertainty:  %8.4f\n",b,sigb);
  	printf("   chi-squared:  %8.4f  for  %4d  points\n",chi2,NPT);
  	printf("   goodness-of-fit:  %8.4f\n",q);
  	printf("\nAccording to routine MEDFIT the result is:\n");
  	medfit(x,y,NPT,&a,&b,&abdev);
  	printf("   a =  %8.4f\n",a);
  	printf("   b =  %8.4f\n",b);
  	printf("   absolute deviation (per data point): %8.4f\n",abdev);
  	printf("   (note: gaussian SPREAD is %8.4f)\n",SPREAD);
  	free_vector(sig,1,NDATA);
  	free_vector(y,1,NDATA);
  	free_vector(x,1,NDATA);
  	return 0;
  }
  #undef NRANSI
  