/* nag_bessel_k_alpha (s18egc) Example Program.
 *
 * Copyright 2014 Numerical Algorithms Group.
 *
 * NAG C Library
 *
 * Mark 6, 2000.
 * Mark 8 revised, 2004.
 */

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

int main(void)
{
  Integer  exit_status = 0, i, ia, ja, nl;
  NagError fail;
  double   alpha, *b = 0, x;

  INIT_FAIL(fail);

  /* Skip heading in data file */
  scanf("%*[^\n]");
  printf("nag_bessel_k_alpha (s18egc) Example Program Results\n");
  if (!(b = NAG_ALLOC(101, double)))
    {
      printf("Allocation failure\n");
      exit_status = -1;
      goto END;
    }
  while (scanf("%lf %ld %ld %ld%*[^\n]", &x, &ia, &ja,
                &nl) != EOF)
    {
      printf("  x      ia     ja     nl\n");
      printf("%4.1f %6ld %6ld %6ld\n\n", x, ia, ja,
              nl);
      /* nag_bessel_k_alpha (s18egc).
       * Modified Bessel functions K_(alpha+n)(x) for real
       * x > 0, selected values of alpha >= 0 and
       * n = 0,1,...,N
       */
      nag_bessel_k_alpha(x, ia, ja, nl, b, &fail);
      if (fail.code != NE_NOERROR)
        {
          printf("Error from nag_bessel_k_alpha (s18egc).\n%s\n",
                  fail.message);
          exit_status = 1;
          goto END;
        }
      printf(" Requested values of K_alpha(x)\n\n");
      alpha = (double) ia / (double) ja;
      printf("     alpha        K_alpha(x)\n");
      for (i = 0; i <= nl; ++i)
        {
          printf(" %13.4e %13.4e\n", alpha, b[i]);
          alpha += 1.0;
        }
    }

 END:
  NAG_FREE(b);
  return exit_status;
}