using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using L = Science.Mathematics.LinearAlgebra;

namespace Strang3Ed.Chapter02.Section5
{
    public class Example03
    {
        public Example03()
        {
        }
        private string result;
        public string Result
        {
            get { return result; }
        }
        public void Compute()
        {
            double[,] x = {{1.0,0.0,0.0},
                           {-5.0,1.0,0.0},
                           {0.0,0.0,1.0}};

            L.Matrix E = new L.Matrix(x);

            L.Matrix Ei = E.Inverse;

            double[,] y  = {{1.0,0.0,0.0},
                           {0.0,1.0,0.0},
                           {0.0,-4.0,1.0}};

            L.Matrix F = new L.Matrix(y);

            L.Matrix Fi = F.Inverse;

            L.Matrix FE = F * E;

            result += FE[0, 0].ToString() + "    ";
            result += FE[0, 1].ToString() + "    ";
            result += FE[0, 2].ToString() + "\r\n";

            result += FE[1, 0].ToString() + "    ";
            result += FE[1, 1].ToString() + "    ";
            result += FE[1, 2].ToString() + "\r\n";

            result += FE[2, 0].ToString() + "    ";
            result += FE[2, 1].ToString() + "    ";
            result += FE[2, 2].ToString() + "\r\n" + "\r\n";

            L.Matrix EiFi = Ei * Fi;

            result += EiFi[0, 0].ToString() + "    ";
            result += EiFi[0, 1].ToString() + "    ";
            result += EiFi[0, 2].ToString() + "\r\n";

            result += EiFi[1, 0].ToString() + "    ";
            result += EiFi[1, 1].ToString() + "    ";
            result += EiFi[1, 2].ToString() + "\r\n";

            result += EiFi[2, 0].ToString() + "    ";
            result += EiFi[2, 1].ToString() + "    ";
            result += EiFi[2, 2].ToString() + "\r\n" + "\r\n";
        }
    }
}
/*
1    0    0
-5    1    0
20    -4    1

1    0    0
5    1    0
0    4    1
*/