/* nag_cubic_roots (c02akc) Example Program.
 *
 * Copyright 2000 Numerical Algorithms Group.
 *
 * NAG C Library
 *
 * Mark 6, 2000.
 */

#include <stdio.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <nagc02.h>


int main(void)
{
  double *errest=0, *zeroi=0, *zeror=0;
  double r, s, t, u;
  Integer i;
  Integer exit_status=0;
  NagError fail;

  INIT_FAIL(fail);
  Vprintf("c02akc Example Program Results\n\n");

  if
  (
    ! (errest = NAG_ALLOC(3, double)) ||
    ! (zeroi  = NAG_ALLOC(3, double)) ||
    ! (zeror  = NAG_ALLOC(3, double))
  )
    {
      Vprintf ("Allocation failure\n");
      exit_status=-1;
      goto END;
    }

  /* Skip heading in data file */
  Vscanf("%*[^\n] ");
  Vscanf("%lf %lf %lf %lf ", &u, &r, &s, &t);

  c02akc  (u, r, s, t, zeror, zeroi, errest, &fail);
  if (fail.code == NE_NOERROR)
    {
      Vprintf("\n Roots of cubic equation             Error estimates\n");
      Vprintf("                                   (machine-dependent)\n\n");
      for (i = 0; i <= 2; ++i)
        {
          Vprintf(" z = %10.5f %10.5f%s         %g\n",
                    zeror[i], zeroi[i], "*i", errest[i]);
        }
    }
  else
    {
      Vprintf("Error from c02akc.\n%s\n", fail.message);
      exit_status = 1;
      goto END;
    }

 END:
  if (errest) NAG_FREE (errest);
  if (zeroi)  NAG_FREE (zeroi);
  if (zeror)  NAG_FREE (zeror);
  return exit_status;
}