/* nag_2d_cheb_eval (e02cbc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 * Mark 7b revised, 2004.
 */

#include <stdio.h>
#include <nag.h>
#include <nagx04.h>
#include <nag_stdlib.h>
#include <nage02.h>

int main(int argc, char *argv[])
{
  FILE     *fpin, *fpout;
  /* Scalars */
  double   x1, xm, xmax, xmin, y, ymax, ymin;
  Integer  exit_status, i, j, k, l, m, n, ncoef, one;
  NagError fail;

  /* Arrays */
  double   *a = 0, *ff = 0, *x = 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);
  exit_status = 0;
  fprintf(fpout, "nag_2d_cheb_eval (e02cbc) Example Program Results\n");

  /* Skip heading in data file */
  fscanf(fpin, "%*[^\n] ");
  while (fscanf(fpin, "%ld%ld%ld%*[^\n] ", &n, &k, &l) != EOF)
    {
      /* Allocate array a */
      ncoef = (k + 1) * (l + 1);
      if (!(a = NAG_ALLOC(ncoef, double)))
        {
          fprintf(fpout, "Allocation failure\n");
          exit_status = -1;
          goto END;
        }

      for (i = 0; i < ncoef; ++i)
        fscanf(fpin, "%lf", &a[i]);
      fscanf(fpin, "%*[^\n] ");

      fscanf(fpin, "%lf%lf%*[^\n] ", &ymin, &ymax);

      for (i = 0; i < n; ++i)
        {
          fscanf(fpin, "%lf%ld%lf%lf%lf%lf%*[^\n] ",
                 &y, &m, &xmin, &xmax, &x1, &xm);

          /* Allocate arrays x and ff */
          if (!(x = NAG_ALLOC(m, double)) ||
              !(ff = NAG_ALLOC(m, double)))
            {
              fprintf(fpout, "Allocation failure\n");
              exit_status = -1;
              goto END;
            }

          for (j = 0; j < m; ++j)
            x[j] = x1 + (xm - x1) * (double) j / (double)(m - 1);

          one = 1;
          /* nag_2d_cheb_eval (e02cbc).
           * Evaluation of fitted polynomial in two variables
           */
          nag_2d_cheb_eval(one, m, k, l, x, xmin, xmax, y, ymin, ymax,
                           ff, a, &fail);
          if (fail.code != NE_NOERROR)
            {
              fprintf(fpout, "Error from nag_2d_cheb_eval (e02cbc).\n%s\n",
                      fail.message);
              exit_status = 1;
              goto END;
            }

          fprintf(fpout, "\n");
          fprintf(fpout, "y = %13.4e\n", y);
          fprintf(fpout, "\n");
          fprintf(fpout, "  i     x(i)      Poly(x(i),y)\n");
          for (j = 0; j < m; ++j)
            fprintf(fpout, "%3ld%13.4e%13.4e\n", j, x[j], ff[j]);

          if (ff) NAG_FREE(ff);
          if (x) NAG_FREE(x);
        }

      if (a) NAG_FREE(a);
    }

 END:
  if (fpin != stdin) fclose(fpin);
  if (fpout != stdout) fclose(fpout);
  if (a) NAG_FREE(a);
  if (ff) NAG_FREE(ff);
  if (x) NAG_FREE(x);

  return exit_status;
}