/* nag_stat_summary_onevar (g01atc) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.2, 2024.
 */

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

int main(void) {
  /* Integer scalar and array declarations */
  Integer b, i, ierr, iwt, nb, pn;
  Integer exit_status = 0;

  /* NAG structures and types */
  NagError fail;

  /* Double scalar and array declarations */
  double xkurt, xmax, xmean, xmin, xsd, xskew;
  double rcomm[20];
  double *wt = 0, *x = 0;

  /* Initialize the error structure */
  INIT_FAIL(fail);

  printf("nag_stat_summary_onevar (g01atc) Example Program Results\n\n");

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

  /* Initialize the number of valid observations processed so far */
  pn = 0;

  /* Loop over each block of data */
  for (b = 0;;) {
    /* Read in the number of observations in this block and a flag indicating
       whether weights have been supplied (iwt = 1) or not (iwt = 0) */
    ierr = scanf("%" NAG_IFMT "%" NAG_IFMT "", &nb, &iwt);
    if (ierr == EOF || ierr < 2)
      break;
    scanf("%*[^\n] ");

    /* Keep a running total of the number of blocks of data */
    b++;

    /* Reallocate X to the required size */
    NAG_FREE(x);
    if (!(x = NAG_ALLOC(nb, double))) {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }

    /* Read in the data for this block */
    if (iwt) {
      /* Weights supplied, so reallocate WT to the required size */
      NAG_FREE(wt);
      if (!(wt = NAG_ALLOC(nb, double))) {
        printf("Allocation failure\n");
        exit_status = -2;
        goto END;
      }
      for (i = 0; i < nb; i++)
        scanf("%lf%lf", &x[i], &wt[i]);
    } else {
      /* No weights */
      NAG_FREE(wt);
      wt = 0;

      for (i = 0; i < nb; i++)
        scanf("%lf", &x[i]);
    }
    scanf("%*[^\n] ");

    /* Call nag_stat_summary_onevar (g01atc) to update the summaries for
       this block of data */
    nag_stat_summary_onevar(nb, x, wt, &pn, &xmean, &xsd, &xskew, &xkurt, &xmin,
                            &xmax, rcomm, &fail);
    if (fail.code != NE_NOERROR && fail.code != NE_CASES_ONE &&
        fail.code != NE_ZERO_VARIANCE && fail.code != NE_CASES_ZERO) {
      printf("Error from nag_stat_summary_onevar (g01atc).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }
  }

  /* Display the results */
  printf(" Data supplied in %" NAG_IFMT " blocks\n", b);
  if (fail.code == NE_CASES_ZERO)
    printf(" No valid observations supplied. All weights are zero.\n");
  else {
    printf(" %" NAG_IFMT " valid observations\n", pn);
    printf(" Mean          %13.2f\n", xmean);
    if (fail.code == NE_CASES_ONE) {
      printf("   Unable to calculate the standard deviation,");
      printf(" skewness or kurtosis\n");
    } else {
      printf(" Std devn      %13.2f\n", xsd);
      if (fail.code == NE_ZERO_VARIANCE)
        printf("   Unable to calculate the skewness and kurtosis\n");
      else {
        printf(" Skewness      %13.2f\n", xskew);
        printf(" Kurtosis      %13.2f\n", xkurt);
      }
    }
    printf(" Minimum       %13.2f\n", xmin);
    printf(" Maximum       %13.2f\n", xmax);
  }

END:
  NAG_FREE(x);
  NAG_FREE(wt);

  return (exit_status);
}