/* nag_correg_linregm_estfunc (g02dnc) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.3, 2024.
 */

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

#define X(I, J) x[(I)*tdx + J]
int main(void) {
  Integer exit_status = 0, i, ip, j, m, n, nestern, rank, *sx = 0, tdq, tdx;
  double *b = 0, *com_ar = 0, *cov = 0, df, *f = 0, *h = 0, *p = 0;
  double *q = 0, *res = 0, rss, *se = 0, sestat, stat, t, tol;
  double *wt = 0, *wtptr, *x = 0, *y = 0;
  char nag_enum_arg[40];
  Nag_Boolean est, svd, weight;
  Nag_IncludeMean mean;
  NagError fail;

  INIT_FAIL(fail);

  printf("nag_correg_linregm_estfunc (g02dnc) Example Program Results\n");
  /* Skip heading in data file */
  scanf("%*[^\n]");
  scanf("%" NAG_IFMT " %" NAG_IFMT "", &n, &m);
  scanf(" %39s", nag_enum_arg);
  /* nag_enum_name_to_value (x04nac).
   * Converts NAG enum member name to value
   */
  weight = (Nag_Boolean)nag_enum_name_to_value(nag_enum_arg);
  scanf(" %39s", nag_enum_arg);
  mean = (Nag_IncludeMean)nag_enum_name_to_value(nag_enum_arg);

  if (n >= 2 && m >= 1) {
    if (!(h = NAG_ALLOC(n, double)) || !(res = NAG_ALLOC(n, double)) ||
        !(wt = NAG_ALLOC(n, double)) || !(x = NAG_ALLOC(n * m, double)) ||
        !(y = NAG_ALLOC(n, double)) || !(sx = NAG_ALLOC(m, Integer))) {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }
    tdx = m;
  } else {
    printf("Invalid n or m.\n");
    exit_status = 1;
    return exit_status;
  }
  if (weight) {
    wtptr = wt;
    for (i = 0; i < n; i++) {
      for (j = 0; j < m; j++)
        scanf("%lf", &X(i, j));
      scanf("%lf%lf", &y[i], &wt[i]);
    }
  } else {
    wtptr = (double *)0;
    for (i = 0; i < n; i++) {
      for (j = 0; j < m; j++)
        scanf("%lf", &X(i, j));
      scanf("%lf", &y[i]);
    }
  }
  for (j = 0; j < m; j++)
    scanf("%" NAG_IFMT "", &sx[j]);
  scanf("%" NAG_IFMT "", &ip);

  if (!(b = NAG_ALLOC(ip, double)) ||
      !(cov = NAG_ALLOC(ip * (ip + 1) / 2, double)) ||
      !(f = NAG_ALLOC(ip, double)) || !(p = NAG_ALLOC(ip * (ip + 2), double)) ||
      !(q = NAG_ALLOC(n * (ip + 1), double)) || !(se = NAG_ALLOC(ip, double)) ||
      !(com_ar = NAG_ALLOC(ip * ip + ip, double))) {
    printf("Allocation failure\n");
    exit_status = -1;
    goto END;
  }
  tdq = ip + 1;

  /* Set tolerance */
  tol = 0.00001e0;

  /*
   *    Find initial estimates using g02dac
   */
  /* nag_correg_linregm_fit (g02dac).
   * Fits a general (multiple) linear regression model
   */
  nag_correg_linregm_fit(mean, n, x, tdx, m, sx, ip, y, wtptr, &rss, &df, b, se,
                         cov, res, h, q, tdq, &svd, &rank, p, tol, com_ar,
                         &fail);
  if (fail.code != NE_NOERROR) {
    printf("Error from nag_correg_linregm_fit (g02dac).\n%s\n", fail.message);
    exit_status = 1;
    goto END;
  }

  printf("\n");
  printf("Estimates from g02dac\n\n");
  printf("Residual sum of squares = %13.4e\n", rss);
  printf("Degrees of freedom = %3.1f\n\n", df);
  printf("Variable   Parameter estimate   Standard error\n\n");
  for (j = 0; j < ip; j++)
    printf("%6" NAG_IFMT "%20.4e%20.4e\n", j + 1, b[j], se[j]);
  printf("\n");
  scanf("%" NAG_IFMT "", &nestern);
  for (i = 1; i <= nestern; ++i) {
    for (j = 0; j < ip; ++j)
      scanf("%lf", &f[j]);

    /* nag_correg_linregm_estfunc (g02dnc).
     * Estimate of an estimable function for a general linear
     * regression model
     */
    nag_correg_linregm_estfunc(ip, rank, b, cov, p, f, &est, &stat, &sestat, &t,
                               tol, &fail);

    if (fail.code == NE_NOERROR || fail.code == NE_RANK_EQ_IP) {
      printf("\n");
      printf("Function %" NAG_IFMT "\n\n", i);
      for (j = 0; j < ip; ++j)
        printf("%8.2f%c", f[j], (j % 5 == 4 || j == ip - 1) ? '\n' : ' ');
      printf("\n");
      if (est)
        printf(" stat = %10.4f  se = %10.4f   t = %10.4f\n", stat, sestat, t);
      else
        printf("Function not estimable\n");
    } else {
      printf("Error from nag_correg_linregm_estfunc (g02dnc).\n%s\n",
             fail.message);
      exit_status = 1;
      goto END;
    }
  }
END:
  NAG_FREE(h);
  NAG_FREE(res);
  NAG_FREE(wt);
  NAG_FREE(x);
  NAG_FREE(y);
  NAG_FREE(sx);
  NAG_FREE(b);
  NAG_FREE(cov);
  NAG_FREE(f);
  NAG_FREE(p);
  NAG_FREE(q);
  NAG_FREE(se);
  NAG_FREE(com_ar);
  return exit_status;
}