/* nag_regsn_mult_linear_upd_model(g02ddc) Example Program
 *
 * Copyright 1991 Numerical Algorithms Group.
 *
 * Mark 2, 1991.
 */

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

#define NMAX 12
#define MMAX 5
#define TDX MMAX
#define TDQ MMAX+1

int main(void)
{
  double   rss, tol;
  Integer  i, ip, rank, j, m, n;
  double df;
  Boolean  svd;
  char     weight;
  double   b[MMAX], cov[MMAX*(MMAX+1)/2], p[MMAX*(MMAX+2)],
  q[NMAX][MMAX+1], se[MMAX], wt[NMAX], x[NMAX][MMAX], xe[NMAX];
  double   *wtptr;
  static   NagError fail;

  Vprintf("g02ddc Example Program Results\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n]");
  Vscanf("%ld %ld %c", &n, &m, &weight);
  if (weight=='w')
    wtptr = wt;
  else
    wtptr = (double *)0;

  if (n<=NMAX && m<MMAX)
    {
      if (wtptr)
        {
          for (i=0; i<n; i++)
            {
              for (j=0; j<m; j++)
                Vscanf("%lf", &x[i][j]);
              Vscanf("%lf%lf", &q[i][0], &wt[i]);
            }
        }
      else
        {
          for (i=0; i<n; i++)
            {
              for (j=0; j<m; j++)
                Vscanf("%lf", &x[i][j]);
              Vscanf("%lf", &q[i][0]);
            }
        }
      /* Set tolerance */
      tol = 0.000001e0;
      ip = 0;
      for (j=0; j<m; ++j)
        {
          /*
           *        Fit model using g02dec
           */
          for (i=0; i<n; i++)
            xe[i] = x[i][j];
          g02dec(n, ip, &q[0][0], (Integer)(TDQ), p, wtptr, xe, &rss,
                 tol, &fail);
          if (fail.code==NE_NOERROR)
            ip += 1;
          else if (fail.code==NE_NVAR_NOT_IND)
            Vprintf(" * New variable not added * \n");
          else
            {
              Vprintf("%s\n", fail.message);
              return EXIT_FAILURE;
            }
        }
      rss = 0.0;
      g02ddc(n, ip, &q[0][0], (Integer)(TDQ), &rss, &df, b, se, cov, &svd,
             &rank, p, tol, NAGERR_DEFAULT);

      Vprintf("\n");
      if (svd)
        Vprintf("Model not of full rank\n\n");
      Vprintf("Residual sum of squares = %12.4e\n", rss);
      Vprintf("Degrees of freedom = %3.1f\n\n", df);
      Vprintf("Variable    Parameter estimate   Standard error\n\n");
      for (j=0; j<ip; j++)
        Vprintf("%6ld%20.4e%20.4e\n", j+1, b[j], se[j]);
      Vprintf("\n");
    }
  else
    {
      Vfprintf(stderr, "One or both of m and n are out of range:"
               " m = %-3ld while  n = %-3ld\n", m, n);

      return EXIT_FAILURE;
    }
  return EXIT_SUCCESS;
}