/* nag_glm_est_func (g02gnc) Example Program.
 *
 * Copyright 1996 Numerical Algorithms Group.
 *
 * Mark 4, 1996.
 *
 * Mark 6 revised, 2000.
 * Mark 8 revised, 2004.
 */

#include <nag.h>
#include <nagx04.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nagg02.h>

#define X(I, J) x[(I) *tdx + J]
#define V(I, J) v[(I) *tdv + J]
int main(int argc, char *argv[])
{
  FILE        *fpin, *fpout;
  Nag_Boolean est;
  Integer     exit_status = 0, i, ip, j, m, max_iter, n, nestfn, print_iter,
              rank;
  Integer     *sx = 0, tdv, tdx;
  NagError    fail;
  double      dev, df, eps, ex_power, sestat, stat, tol, z;
  double      *b = 0, *cov = 0, *f = 0, *se = 0, *v = 0, *wtptr, *x = 0;
  double      *y = 0;

  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_glm_est_func (g02gnc) Example Program Results\n");
  /* Skip heading in data file */
  fscanf(fpin, "%*[^\n]");
  fscanf(fpin, "%ld %ld %ld", &n, &m, &print_iter);

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

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

  /* Set control parameters */
  max_iter = 10;
  tol = 5e-5;
  eps = 1e-6;
  ex_power = 0.0;

  /* Fit Log-linear model using nag_glm_poisson (g02gcc) */

  /* nag_glm_poisson (g02gcc).
   * Fits a generalized linear model with Poisson errors
   */
  nag_glm_poisson(Nag_Log, Nag_MeanInclude, n, x, tdx,
                  m, sx, ip, y, wtptr, (double *) 0, 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)
    {
      fprintf(fpout, "\nDeviance = %13.4e\n", dev);
      fprintf(fpout, "Degrees of freedom = %3.1f\n\n", df);
      fprintf(fpout, "       Estimate     Standard error\n\n");
      for (i = 0; i < ip; i++)
        fprintf(fpout, "%14.4f%14.4f\n", b[i], se[i]);
      fprintf(fpout, "\n");
      fscanf(fpin, "%ld", &nestfn);
      for (i = 1; i <= nestfn; ++i)
        {
          for (j = 0; j < ip; ++j)
            fscanf(fpin, "%lf", &f[j]);

          /* nag_glm_est_func (g02gnc).
           * Estimable function and the standard error of a
           * generalized linear model
           */
          nag_glm_est_func(ip, rank, b, cov, v,
                           tdv, f, &est, &stat, &sestat, &z, tol,
                           &fail);

          if (fail.code == NE_NOERROR || fail.code == NE_RANK_EQ_IP)
            {
              fprintf(fpout, "\n");
              fprintf(fpout, "Function %ld\n\n", i);
              for (j = 0; j < ip; ++j)
                fprintf(fpout, "%8.2f%c", f[j],
                        (j%5 == 4 || j == ip-1)?'\n':' ');
              fprintf(fpout, "\n");
              if (est)
                fprintf(fpout, "stat = %10.4f  sestat = %10.4f   z = %10.4f\n",
                        stat, sestat, z);
              else
                fprintf(fpout, "Function not estimable\n");
            }
          else
            {
              fprintf(fpout, "Error from nag_glm_est_func (g02gnc).\n%s\n",
                      fail.message);
              exit_status = 1;
              goto END;
            }
        }
    }
  else
    {
      fprintf(fpout, "Error from nag_glm_poisson (g02gcc).\n%s\n",
              fail.message);
      exit_status = 1;
      goto END;
    }
 END:
  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);
  if (x) NAG_FREE(x);
  if (y) NAG_FREE(y);
  if (sx) NAG_FREE(sx);
  if (b) NAG_FREE(b);
  if (f) NAG_FREE(f);
  if (v) NAG_FREE(v);
  if (cov) NAG_FREE(cov);
  if (se) NAG_FREE(se);
  return exit_status;
}