/* nag_glm_gamma (g02gdc) Example Program.
 *
 * Copyright 1996 Numerical Algorithms Group.
 *
 * Mark 4, 1996.
 * Mark 8 revised, 2004.
 *
 */

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <ctype.h>
#include <nagg02.h>

#define X(I, J) x[(I) *tdx + J]
#define V(I, J) v[(I) *tdv + J]

int main(void)
{
  Integer         exit_status = 0, i, ip, j, m, max_iter, n, print_iter, rank;
  Integer         *sx = 0;
  Integer         tdv, tdx;
  double          dev, df, eps, ex_power, scale, tol;
  double          *b = 0, *cov = 0, *offsetptr = (double *) 0;
  double          *se = 0, *v = 0, *wt = 0, *wtptr, *x = 0, *y = 0;
  char            nag_enum_arg[40];
  Nag_IncludeMean mean;
  Nag_Link        link;
  Nag_Boolean     weight;
  NagError        fail;

  INIT_FAIL(fail);

  printf("nag_glm_gamma (g02gdc) Example Program Results\n");
  /* Skip heading in data file */
  scanf("%*[^\n]");
  scanf(" %s", nag_enum_arg);
  /* nag_enum_name_to_value(x04nac).
   * Converts NAG enum member name to value
   */
  link = (Nag_Link) nag_enum_name_to_value(nag_enum_arg);
  scanf(" %s", nag_enum_arg);
  mean = (Nag_IncludeMean) nag_enum_name_to_value(nag_enum_arg);
  scanf(" %s", nag_enum_arg);
  weight = (Nag_Boolean) nag_enum_name_to_value(nag_enum_arg);
  scanf("%ld %ld %ld %lf", &n, &m, &print_iter,
         &scale);

  if (n >= 2 && m >= 1)
    {
      if (!(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("%ld", &sx[j]);

  /* Calculate ip */
  ip = 0;
  for (j = 0; j < m; j++)
    if (sx[j] > 0) ip += 1;
  if (mean == Nag_MeanInclude)
    ip += 1;
  if (link == Nag_Expo)
    scanf("%lf", &ex_power);
  else
    ex_power = 0.0;

  if (!(b = NAG_ALLOC(ip, double)) ||
      !(v = NAG_ALLOC(n*(ip+6), double)) ||
      !(se = NAG_ALLOC(ip, double)) ||
      !(cov = NAG_ALLOC(ip*(ip+1)/2, double)))
    {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }
  tdv = ip+6;


  /* Set other control parameters */
  max_iter = 10;
  tol = 5e-5;
  eps = 1e-6;

  /* nag_glm_gamma (g02gdc).
   * Fits a generalized linear model with gamma errors
   */
  nag_glm_gamma(link, mean, n, x, tdx, m, sx, ip, y,
                wtptr, offsetptr, &scale, ex_power, &dev, &df, b, &rank,
                se, cov, v, tdv, tol, max_iter,
                print_iter, "", eps, &fail);

  if (fail.code == NE_NOERROR || fail.code == NE_LSQ_ITER_NOT_CONV ||
      fail.code == NE_RANK_CHANGED || fail.code == NE_ZERO_DOF_ERROR)
    {
      if (fail.code != NE_NOERROR) {
        printf("Error from nag_glm_gamma (g02gdc).\n%s\n",
                fail.message);
      }
      printf("\nDeviance = %13.4e\n", dev);
      printf("Degrees of freedom = %3.1f\n\n", df);
      printf("       Estimate     Standard error\n\n");
      for (i = 0; i < ip; i++)
        printf("%14.4f%14.4f\n", b[i], se[i]);
      printf("\n");
      printf("     y   fitted value  Residual  Leverage\n\n");
      for (i = 0; i < n; ++i)
        {
          printf("%7.1f%10.2f%12.4f%10.3f\n", y[i], V(i, 1), V(i, 4),
                  V(i, 5));
        }
    }
  else
    {
      printf("Error from nag_glm_gamma (g02gdc).\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

 END:
  if (wt) NAG_FREE(wt);
  if (x) NAG_FREE(x);
  if (y) NAG_FREE(y);
  if (sx) NAG_FREE(sx);
  if (b) NAG_FREE(b);
  if (v) NAG_FREE(v);
  if (se) NAG_FREE(se);
  if (cov) NAG_FREE(cov);

  return exit_status;
}