#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "local_proto.h"


double *cramer_von_mises_exp  (double *x, int n)
{
  static double y[2];
  double *xcopy, mean=0.0, fx, fn2, sum4 = 0.0;
  int i;

  if ((xcopy = (double *) malloc (n * sizeof (double))) == NULL)
  {
      fprintf (stderr, "Memory error in cramer_von_mises_exp\n");
      exit(EXIT_FAILURE);
  }

  for (i = 0; i < n; ++i)
  {
    xcopy[i] = x[i];
    mean += x[i];
  }
  mean /= n;

  qsort (xcopy, n, sizeof (double), dcmp);

  for (i = 0; i < n; ++i)
  {
    /*-
    a = (2 * i + 1) * log (fx);
    b = (2 * i + 1) * (xcopy[n-i-1] * (-1.0 / mean));
    sum3 += a + b;
    */
    fx = 1 - exp (xcopy[i] * (-1.0 / mean));
    fn2 = (double) (2.0 * i + 1) / (2 * n);
    sum4 += (fx - fn2) * (fx - fn2);
  }

  /*-
  cvm = 1.0 / (n * 12) + sum4;
  cvmod = cvm * (0.16 / n + 1.0);
  */
  y[0] = (1.0 / (n * 12) + sum4)*(0.16 / n + 1.0);

#ifdef NOISY
  fprintf (stdout,"  TEST16 CVM(E) =%10.4f\n", y[0]);
#endif				/* NOISY */

  free (xcopy);

  return y;
}
