//      c05zd Example Program Text
//      C# version, NAG Copyright 2008
using System;
using NagLibrary;
using System.Globalization;
namespace NagDotNetExamples
{
  public class C05ZDE
  {
    static void Main(String[] args)
    {
      StartExample();
    }
    public static void StartExample()
    {
      try
      {
        const int m = 15;
        const int n = 3;
        int i,  mode; double[] err = new double[m];
        double[,] fjac = new double[m, n];
        double[] fvec = new double[m];
        double[] fvecp = new double[m];
        double[] x = new double[n];
        double[] xp = new double[n];
        int ifail;
        Console.WriteLine("c05zd Example Program Results");
        //
        x[0] = 9.20e-1;
        x[1] = 1.30e-1;
        x[2] = 5.40e-1;
        mode = 1;
        //
	      // C05.c05za(m, n, x, fvec, fjac, xp, fvecp, mode, err, out ifail);
        C05.c05zd(mode, m, n, x, fvec, fjac, xp, fvecp,  err, out ifail);
        //
        fcn(m, n, x, fvec, fjac, m, 1);
        fcn(m, n, x, fvec, fjac, m, 2);
        fcn(m, n, xp, fvecp, fjac, m, 1);
        //
        Console.WriteLine("");
        Console.WriteLine(" {0}", "     fvec at x = ");
        for (i = 1; i <= n; i++)
        {
          Console.Write(" {0, 10:f4}{1}", x[i - 1], i%3==0?"\n":"");
        }
        Console.WriteLine("");
        Console.WriteLine("");
        for (i = 1; i <= m; i++)
        {
          Console.Write(" {0,10:f4}{1}", fvec[i - 1],i%3==0?"\n":"");
        }
        Console.WriteLine("");
        Console.WriteLine("");
        Console.WriteLine(" {0}", "     fvecp at xp = ");
        for (i = 1; i <= n; i++)
        {
          Console.Write(" {0,10:f4}", xp[i - 1]);
        }
        Console.WriteLine("");
        Console.WriteLine("");
        for (i = 1; i <= m; i++)
        {
          Console.Write(" {0,10:f4}{1}", fvecp[i - 1], i % 3 == 0 ? "\n" : "");
        }
        Console.WriteLine("");
        //
        mode = 2;
        //
        C05.c05zd( mode,m, n, x, fvec, fjac, xp, fvecp, err,out ifail);
        //
        Console.WriteLine("");
        Console.WriteLine(" {0}", "     err");
        Console.WriteLine("");
        for (i = 1; i <= m; i++)
        {
          Console.Write(" {0,10:f4}{1}", err[i - 1], i % 3 == 0 ? "\n" : "");
        }
        Console.WriteLine("");
        //
        //
      }
      catch (Exception e)
      {
        Console.WriteLine(e.Message);
        Console.WriteLine("Exception Raised");
      }
      Console.WriteLine("");
    }
    //
    public static void fcn(int m, int n, double[] x, double[] fvec, double[,] fjac,
    int ldfjac,  int iflag) { double tmp1,  tmp2,  tmp3,  tmp4;
    int i = 0;
    double[] y = new double[15] { 1.40e-1, 1.80e-1, 2.20e-1, 2.50e-1, 2.90e-1, 3.20e-1, 3.50e-1, 3.90e-1, 3.70e-1, 5.80e-1, 7.30e-1, 9.60e-1, 1.340e0, 2.10e0, 4.390e0 };
    if (iflag != 2)
    {
      for (i = 1; i <= m; i++)
      {
        tmp1 = (double)i;
        tmp2 = m + 1 - i;
        tmp3 = (double)tmp1;
        if (i > (m + 1) / 2)
        {
          tmp3 = (double)tmp2;
        }
        fvec[i - 1] = y[i - 1] - (x[0] + tmp1 / (x[1] * tmp2 + x[2] * tmp3));
      }
    }
    else
    {
      for (i = 1; i <= m; i++)
      {
        tmp1 = (double)i;
        tmp2 = m + 1 - i;
        //
        //            Error introduced into next statement for illustration.
        //            Corrected statement should read    tmp3 = tmp1.
        //
        tmp3 = (double)tmp2;
        if (i > (m + 1) / 2)
        {
          tmp3 = (double)tmp2;
        }
        tmp4 = ((x[1] * tmp2 + x[2] * tmp3)) * ((x[1] * tmp2 + x[2] * tmp3));
        fjac[i - 1, 0] = -1.00e0;
        fjac[i - 1, 1] = tmp1 * tmp2 / tmp4;
        fjac[i - 1, 2] = tmp1 * tmp3 / tmp4;
      }
    }
  }
}
}