//      f08an Example Program Text
//      C# version, NAG Copyright 2008
using System;
using NagLibrary;
using System.Globalization;
namespace NagDotNetExamples
{
  public class F08ANE
  {
    static string datafile = "ExampleData/f08ane.d";
    static void Main(String[] args)
    {
      if (args.Length == 1)
      {
        datafile = args[0];
      }
      StartExample();
    }
    public static void StartExample()
    {
      try
      {
        DataReader sr = new DataReader(datafile);
        double rnorm=0.0;
        int i,   info,   j,   m,   n; 
        //      Skip heading in data file 
        sr.Reset();
        sr.Reset();
        m = int.Parse(sr.Next());
        n = int.Parse(sr.Next());
        int nrhs = 1;
        Complex[,] a = new Complex[m, n];
        Complex[,] b = new Complex[Math.Max(m,n),nrhs];
        Console.WriteLine("f08an Example Program Results");
        Console.WriteLine("");
        if (m >0 && n > 0  && m >= n)
        {
          // 
          //         Read A and B from data file
          // 
          sr.Reset();
          for (i = 1 ; i <= m ; i++)
          {
            for (j = 1 ; j <= n ; j++)
            {
              a[i - 1 , j - 1] = Complex.Parse(sr.Next());
            }
          }
          sr.Reset();
          for (i = 1 ; i <= m ; i++)
          {
            b[i - 1,0] = Complex.Parse(sr.Next());
          }
          // 
          //         Solve the least squares problem min( norm2(b - Ax) ) for x
          // 
          F08.f08an("No transpose", m, n, nrhs, a, b, out info);

          if (info < 0)
          {
              return;
          }
          // 
          //         Print solution
          // 

         
              Console.WriteLine(" {0}", "Least squares solution");
              for (i = 1; i <= n; i++)
              {
                  Console.Write(" {0, 10:f4}", b[i - 1, 0]);
              }
              Console.WriteLine();
              // 
              //         Compute and print estimate of the square root of the residual
              //         sum of squares
              // 
              Complex[] ArraySlice_b = new Complex[m - n];
              for (i = 0; i < m - n; i++)
                  ArraySlice_b[i] = b[n + i, 0];
              int ifail;
              rnorm = F06.f06jj(m - n, ArraySlice_b, 1, out ifail);
              Console.WriteLine("");
              Console.WriteLine(" {0}", "Square root of the residual sum of squares");
              Console.WriteLine("  {0,10:e2}", rnorm);
           
        }
        // 
      }
      catch (Exception e)
      {
        Console.WriteLine(e.Message);
        Console.WriteLine("Exception Raised");
      }
    }
  }
}