/* nag_1d_cheb_eval2 (e02akc) Example Program.
 *
 * Copyright 2001 Numerical Algorithms Group.
 *
 * Mark 7, 2001.
 */

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

int main(int argc, char *argv[])
{
  FILE         *fpout;
  /* Initialized data */
  const double xmin = -0.5;
  const double xmax = 2.5;
  const double a[7] = { 2.53213, 1.13032, 0.2715, 0.04434, 0.00547, 5.4e-4,
                        4e-5 };

  /* Scalars */
  double       p, x;
  Integer      exit_status, i, m, n, one;
  NagError     fail;

  INIT_FAIL(fail);

  /* Check for command-line IO options */
  fpout = nag_example_file_io(argc, argv, "-results", NULL);
  exit_status = 0;
  fprintf(fpout, "nag_1d_cheb_eval2 (e02akc) Example Program Results\n");

  n = 6;
  one = 1;

  fprintf(fpout, "\n");
  fprintf(fpout, "   i   Argument  Value of polynomial\n");

  m = 4;
  for (i = 1; i <= m; ++i)
    {
      x = (xmin * (double)(m - i) + xmax * (double)(i - 1)) /
          (double)(m - 1);
      /* nag_1d_cheb_eval2 (e02akc).
       * Evaluation of fitted polynomial in one variable from
       * Chebyshev series form
       */
      nag_1d_cheb_eval2(n, xmin, xmax, a, one, x, &p, &fail);
      if (fail.code != NE_NOERROR)
        {
          fprintf(fpout, "Error from nag_1d_cheb_eval2 (e02akc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }
      fprintf(fpout, "%4ld%10.4f    %9.4f\n", i, x, p);
    }

 END:
  if (fpout != stdout) fclose(fpout);
  return exit_status;
}