public AbstrSquareMatrix InverseMatrix()
{
double[,] res = new double[N, N * 2];
for (int i = 0; i < N; i++)
{
for (int j = 0; j < N; j++)
{
res[i, j] = Get(i, j);
}
res[i, i + N] = 1;
}
double[,] prev = new double[res.GetLength(0), res.GetLength(1)];
for (int i = 0; i < res.GetLength(0); i++)
{
Array.Copy(res, prev, res.Length);
for (int j = 0; j < res.GetLength(0); j++)
{
for (int k = 0; k < res.GetLength(1); k++)
{
if (j == i)
{
res[j, k] /= prev[i, i];
}
else
{
res[j, k] -= (prev[j, i] * prev[i, k]) / prev[i, i];
}
}
}
}
AbstrSquareMatrix inversed = Create(N);
for (int i = 0; i < res.GetLength(0); i++)
{
for (int j = 0; j < res.GetLength(1) / 2; j++)
{
inversed.Get(i, j) = res[i, j + res.GetLength(1) / 2];
}
}
return(inversed);
}
public static AbstrSquareMatrix operator *(AbstrSquareMatrix m1, AbstrSquareMatrix m2)
{
if (m1.N != m2.N)
{
throw new SizeException(m1.N, m2.N);
}
AbstrSquareMatrix matrixC = m1.Create(m1.N);
for (var i = 0; i < m1.N; i++)
{
for (var j = 0; j < m2.N; j++)
{
matrixC.Get(i, j) = 0;
for (var k = 0; k < m1.N; k++)
{
matrixC.Get(i, j) += m1.Get(i, k) * m2.Get(k, j);
}
}
}
return(matrixC);
}
private static void TestOrdinary()
{
//arrays initializaton
double[,] arr1 = { { 3.5, 5.5, 7.5, 9.5 },
{ 1.5, 2.5, 4.5, 9.5 },
{ 7.5, 2.5, 1.5, 6.5 },
{ 8.5, 7.5, 3.5, 5.5 } };
double[,] arr2 = { { 7.5, 0.5, 3.5, 1.5 },
{ 8.5, 1.5, 9.5, 2.5 },
{ 7.5, 5.5, 6.5, 2.5 },
{ 1.5, 9.5, 7.5, 3.5 } };
double[,] arr3 = { { 8.5, 2.5, 7.5 },
{ 9.5, 1.5, 3.5 },
{ 1.7, 7.9, 3.1 } };
double[,] arr4 = { { 2.5, 10.5, 9.5 },
{ 7.2, 2.4, 5 },
{ 6.5, 7.5, 2.5 } };
OrdinaryMatrix a = new OrdinaryMatrix(arr1);
OrdinaryMatrix b = new OrdinaryMatrix(arr2);
OrdinaryMatrix c = new OrdinaryMatrix(arr3);
OrdinaryMatrix d = new OrdinaryMatrix(arr4);
//arrays printing
Console.WriteLine("A:\n" + a + "B:\n" + b + "C:\n" + c + "D:\n" + d);
//printing of determinants
Console.WriteLine("Determinant of A: " + a.Determinant() +
"\nDeterminant of B: " + b.Determinant() +
"\nDeterminant of C: " + c.Determinant() +
"\nDeterminant of D: " + d.Determinant());
//matrices multiplication
Console.Write("\nA*B:\n" + a * b);
Console.WriteLine("\nC*D:\n" + c * d);
//inversed matrices
AbstrSquareMatrix inv = a.InverseMatrix();
Console.WriteLine("Inversed A:\n" + inv);
Console.WriteLine("Inversed A * A:\n" + (inv * a));
inv = b.InverseMatrix();
Console.WriteLine("Inversed B:\n" + inv);
Console.WriteLine("Inversed B * B:\n" + (inv * b));
inv = c.InverseMatrix();
Console.WriteLine("Inversed C:\n" + inv);
Console.WriteLine("Inversed C * C:\n" + (inv * c));
inv = d.InverseMatrix();
Console.WriteLine("Inversed D:\n" + inv);
Console.WriteLine("Inversed D * D:\n" + (inv * d));
//exceptions catchning
Console.WriteLine("**Exceptions catching*********************");
Console.WriteLine("Trying to create non-square matrix:");
try
{
double[,] non_sq =
{
{ 3.5, 5.5, 7.5 },
{ 1.5, 2.5, 4.5 }
};
OrdinaryMatrix bad = new OrdinaryMatrix(non_sq);
}
catch (AbstrSquareMatrix.SizeException ex)
{
Console.WriteLine("Non-square matrix!!!");
}
Console.WriteLine("Trying to multipply matrices with different N:");
try
{
Console.WriteLine("\nA*C:\n" + a * c);
}
catch (AbstrSquareMatrix.SizeException ex)
{
Console.WriteLine("Sizes of matrices are different!!!");
}
}
