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

#include <stdio.h>
#include <nag.h>
#include <nagx04.h>
#include <nag_stdlib.h>
#include <nagg08.h>

int main(int argc, char *argv[])
{
  FILE     *fpin, *fpout;
  Integer  exit_status = 0, i, n, non_zero;
  NagError fail;
  double   *data = 0, median, p, w, *x = 0, *y = 0, z;

  INIT_FAIL(fail);

  /* Check for command-line IO options */
  fpin = nag_example_file_io(argc, argv, "-data", NULL);
  fpout = nag_example_file_io(argc, argv, "-results", NULL);
  fprintf(fpout, "nag_wilcoxon_test (g08agc) Example Program Results");

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

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

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

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

  fprintf(fpout, "\n\n");
  fprintf(fpout, "%s\n", "Wilcoxon one sample signed ranks test");
  fprintf(fpout, "\n");
  fprintf(fpout, "%s", "Data values\n");
  for (i = 1; i <= n; ++i)
    fprintf(fpout, "%5.1f%s", x[i - 1], i%8?"":"\n");
  for (i = 1; i <= n; ++i)
    fprintf(fpout, "%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)
    {
      fprintf(fpout, "Error from nag_wilcoxon_test (g08agc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }

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

 END:
  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);
  if (x) NAG_FREE(x);
  if (y) NAG_FREE(y);
  if (data) NAG_FREE(data);
  return exit_status;
}