/* nag_complex_eigensystem_sel(f02gcc) Example Program.
 *
 * Copyright 1998 Numerical Algorithms Group.
 *
 * Mark 5, 1998.
 *
 */

#include <nag.h>
#include <nag_stdlib.h>
#include <stdio.h>
#include <nagf02.h>

#define NMAX 8
#define MMAX 3
#define TDA NMAX
#define TDV MMAX

int main(void)
{

  double wl, wu;

  Integer i, j, m, n;
  Integer mest = MMAX;
  Integer  tda, tdv;

  Complex a[NMAX][NMAX], v[NMAX][MMAX], w[NMAX];

  tda = NMAX;
  tdv = MMAX;

  Vprintf("f02gcc Example Program Results\n");

  /* Skip heading in data file */
  Vscanf("%*[^\n]");

  Vscanf("%ld%lf%lf%*[^\n] ",&n, &wl, &wu);
  if (n <= NMAX)
    {

      /* Read a from data file */
      for (i = 0; i < n; ++i)
        for (j = 0; j < n; ++j)
          Vscanf(" ( %lf ,%lf ) ",&a[i][j].re,&a[i][j].im);

      /* Compute selected eigenvalues and eigenvectors of A */

      f02gcc(Nag_Select_Modulus, n, &a[0][0], tda, wl, wu, mest, &m, w,
             &v[0][0], tdv,
             NAGERR_DEFAULT);

      Vprintf("\n\nEigenvalues\n\n");
      for (i = 0; i < m; ++i)
        Vprintf("(%7.4f, %7.4f)%s",w[i].re,  w[i].im, (i+1)%2 == 0 ? "\n" : " ");

      Vprintf("\nEigenvectors\n");
      for (i=1; i<=m; i++)
        Vprintf("%15ld%s", i, i%m == 0 ?"\n" : "");

      for (i = 0; i < n; i++)
        {
          Vprintf("%ld  ", i + 1);
          for (j = 0; j < m; j++)
            Vprintf("(%8.4f, %8.4f)%s", v[i][j].re,
                    v[i][j].im, (j + 1)%m == 0 ? "\n":"  ");
        }
      return EXIT_SUCCESS;
    }
  else
    {
      Vprintf( "Incorrect input value of n.\n");
      return EXIT_FAILURE;
    }
}