/* nag_1d_cheb_eval (e02aec) Example Program.
 *
 * Copyright 1998 Numerical Algorithms Group.
 *
 * Mark 5, 1998.
 * Mark 8 revised, 2004.
 *
 */

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

int main(int argc, char *argv[])
{
  FILE     *fpin, *fpout;
  Integer  exit_status = 0, i, m, n, r;
  NagError fail;
  double   *a = 0, p, xcap;

  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_1d_cheb_eval (e02aec) Example Program Results \n");

  /* Skip heading in data file */
  fscanf(fpin, "%*[^\n]");
  while ((fscanf(fpin, "%ld", &m) != EOF))
    {
      if (m > 0)
        {
          fscanf(fpin, "%ld", &n);
          if (n >= 0)
            {
              if (!(a = NAG_ALLOC(n+1, double)))
                {
                  fprintf(fpout, "Allocation failure\n");
                  exit_status = -1;
                  goto END;
                }
            }
          else
            {
              fprintf(fpout, "Invalid n.\n");
              exit_status = 1;
              return exit_status;
            }
          for (i = 0; i < n+1; ++i)
            fscanf(fpin, "%lf", &a[i]);
          fprintf(fpout, "\n   R       Argument       Value of polynomial \n");
          for (r = 1; r <= m; ++r)
            {
              xcap = (double)(2*r - m - 1) / (double)(m - 1);
              /* nag_1d_cheb_eval (e02aec).
               * Evaluates the coefficients of a Chebyshev series
               * polynomial
               */
              nag_1d_cheb_eval(n+1, a, xcap, &p, &fail);
              if (fail.code != NE_NOERROR)
                {
                  fprintf(fpout, "Error from nag_1d_cheb_eval (e02aec).\n%s\n",
                          fail.message);
                  exit_status = 1;
                  goto END;
                }
              fprintf(fpout, " %3ld%14.4f    %14.4f\n", r, xcap, p);
            }
        }
 END:
      if (fpin != stdin) fclose(fpin);
      if (fpout != stdout) fclose(fpout);
      if (a) NAG_FREE(a);
    }
  return exit_status;
}