/* nag_zeros_real_poly(c02agc) Example Program
 *
 * Copyright 1991 Numerical Algorithms Group.
 *
 * Mark 2, 1991.
 */

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

#define MAXDEG 100

int main(void)
{

  Complex  z[MAXDEG];
  double   a[MAXDEG+1];
  Integer  i, n, nroot;
  Boolean  scale;

  Vprintf("c02agc Example Program Results\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n]");
  Vscanf("%ld", &n);
  scale  = TRUE;
  if (n>0 && n<=MAXDEG)
    {
      for (i=0; i<=n; i++)
        Vscanf("%lf", &a[i]);
      Vprintf("\nDegree of polynomial = %4ld\n\n", n);

      c02agc(n, a, scale, z, NAGERR_DEFAULT);

      Vprintf("Roots of polynomial\n\n");
      nroot = 1;
      while(nroot<=n)
        {
          if (z[nroot-1].im==0.0)
            {
              Vprintf("z = %12.4e\n", z[nroot-1].re);
              nroot += 1;
            }
          else
            {
              Vprintf("z = %12.4e   +/- %14.4e\n", z[nroot-1].re,
                      FABS(z[nroot-1].im));
              nroot += 2;
            }
        }
    }
  else
    {
      Vfprintf(stderr, "Error: n is out of range: n = %3ld\n", n);
      return EXIT_FAILURE;
    }
  return EXIT_SUCCESS;
}