/* nag_wilcoxon_test (g08agc) Example Program.
 *
 * Copyright 2000 Numerical Algorithms Group.
 *
 * Mark 6, 2000.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagg08.h>

int main (void)
{
  Integer exit_status=0, i, n, non_zero;
  NagError fail;
  double *data=0, median, p, w, *x=0, *y=0, z;

  INIT_FAIL(fail);
  Vprintf("nag_wilcoxon_test (g08agc) Example Program Results");

  /* Skip heading in data file */
  Vscanf("%*[^\n]");

  Vscanf("%ld", &n);
  if (!(x = NAG_ALLOC(n, double))
      || !(y = NAG_ALLOC(n, double))
      || !(data = NAG_ALLOC(n, double)))
    {
      Vprintf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

  for (i = 1; i <= n; ++i)
    Vscanf("%lf", &x[i - 1]);

  for (i = 1; i <= n; ++i)
    Vscanf("%lf", &y[i - 1]);

  Vprintf("\n\n");
  Vprintf("%s\n", "Wilcoxon one sample signed ranks test");
  Vprintf("\n");
  Vprintf("%s", "Data values\n");
  for (i = 1; i <= n; ++i)
    Vprintf("%5.1f%s", x[i - 1], i%8?"":"\n");
  for (i = 1; i <= n; ++i)
    Vprintf("%5.1f%s", y[i - 1], i%8?"":"\n");

  for (i = 1; i <= n; ++i)
    data[i - 1] = x[i - 1] - y[i - 1];
  median = 0.0;
  /* nag_wilcoxon_test (g08agc).
   * Performs the Wilcoxon one-sample (matched pairs) signed
   * rank test
   */
  nag_wilcoxon_test(n, data, median, Nag_TwoTail, Nag_IncSignZerosN, &w, &z, &p,
                    &non_zero, &fail);
  if (fail.code != NE_NOERROR)
    {
      Vprintf("Error from nag_wilcoxon_test (g08agc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

  Vprintf("\n\n");
  Vprintf("%s%8.4f\n", "Test statistic            = ", w);
  Vprintf("%s%8.4f\n", "Normalized test statistic = ", z);
  Vprintf("%s%8ld\n","Degrees of freedom        = ", non_zero);
  Vprintf("%s%8.4f\n", "Two tail probability      = ", p);

 END:
  if (x) NAG_FREE(x);
  if (y) NAG_FREE(y);
  if (data) NAG_FREE(data);
  return exit_status;

}