using System;
using System.Runtime.InteropServices; 
using System.Text;
using NagCFunctionsAPI;

public class NagF08Functions
{

  public static void nag_zheevd ( Nag_OrderType order, Nag_JobType job,
                                  Nag_UploType uplo, int n, 
                                  Complex [,] a, double [] w, 
                                  ref string error_message, ref int fail_code)
    {   
        
      int tda = n;
      NagError fail = new NagError();
      fail.char_array = new char [512];
      //        fail.print=1;
      NagFunctions.f08fqc(order, job, uplo, n, a, tda, w, ref fail);
      string tmpstring = new string(fail.char_array);
      error_message = tmpstring;
      fail_code = fail.code;
    } 
  public static void Main()
    {
      int n=4;
      Nag_OrderType order = Nag_OrderType.Nag_RowMajor;
      Nag_JobType job = Nag_JobType.Nag_EigVecs;
      Nag_UploType uplo=Nag_UploType.Nag_Lower;

      int fail_code=0;
      String error_message="";
      Complex [,] a = new Complex[n,n];

      a[0,0].re = 1.0;
      a[0,0].im = 0.0;

      a[1,0].re = 2.0;
      a[1,0].im = 1.0;

      a[1,1].re = 2.0;
      a[1,1].im = 0.0;

      a[2,0].re = 3.0;
      a[2,0].im = 1.0;

      a[2,1].re = 3.0;
      a[2,1].im = 2.0;

      a[2,2].re = 3.0;
      a[2,2].im = 0.0;

      a[3,0].re = 4.0;
      a[3,0].im = 1.0;

      a[3,1].re = 4.0;
      a[3,1].im = 2.0;

      a[3,2].re = 4.0;
      a[3,2].im = 3.0;

      a[3,3].re = 4.0;
      a[3,3].im = 0.0;

      double [] w = new double[n];
      nag_zheevd (order, job, uplo, n, a, w, ref error_message, ref fail_code);
      if (fail_code != 0)
      {
        Console.WriteLine(error_message);
      }
      else
      {
        Console.WriteLine("Eigenvalues");
        for (int i=0; i<n; ++i)
          Console.WriteLine("   {0}     {1, 8:f4}", i+1, w[i]);
        Console.WriteLine();
      }
    }
}