public void MatrixInverseTest()
{
double[][] matrix = MatrixOperations.MatrixCreate(3, 3);
matrix[0][0] = 1.0;
matrix[0][1] = -1.0;
matrix[0][2] = 0.0;
matrix[1][0] = 0.0;
matrix[1][1] = 1.0;
matrix[1][2] = 0.0;
matrix[2][0] = 2.0;
matrix[2][1] = 0.0;
matrix[2][2] = 1.0;
double[][] inv = matrix.MatrixInverse();
var identity = MatrixOperations.MatrixIdentity(3);
double[][] result = inv.MatrixProduct(matrix);
Assert.AreEqual(identity[0][0], result[0][0]);
Assert.AreEqual(identity[0][1], result[0][1]);
Assert.AreEqual(identity[0][2], result[0][2]);
Assert.AreEqual(identity[1][0], result[1][0]);
Assert.AreEqual(identity[1][1], result[1][1]);
Assert.AreEqual(identity[1][2], result[1][2]);
Assert.AreEqual(identity[2][0], result[2][0]);
Assert.AreEqual(identity[2][1], result[2][1]);
Assert.AreEqual(identity[2][2], result[2][2]);
}
public void MatrixInverse2Test()
{
double error = 0.000000000000001;
double[][] matrix = MatrixOperations.MatrixCreate(4, 4);
matrix[0][0] = 4.0;
matrix[0][1] = 3.0;
matrix[0][2] = 2.0;
matrix[0][3] = 2.0;
matrix[1][0] = 0.0;
matrix[1][1] = 1.0;
matrix[1][2] = -3.0;
matrix[1][3] = 3.0;
matrix[2][0] = 0.0;
matrix[2][1] = -1.0;
matrix[2][2] = 3.0;
matrix[2][3] = 3.0;
matrix[3][0] = 0.0;
matrix[3][1] = 3.0;
matrix[3][2] = 1.0;
matrix[3][3] = 1.0;
double[][] inv = matrix.MatrixInverse();
var identity = MatrixOperations.MatrixIdentity(4);
double[][] result = inv.MatrixProduct(matrix);
Assert.IsTrue(Math.Abs(identity[0][0] - result[0][0]) < error);
Assert.IsTrue(Math.Abs(identity[0][1] - result[0][1]) < error);
Assert.IsTrue(Math.Abs(identity[0][2] - result[0][2]) < error);
Assert.IsTrue(Math.Abs(identity[0][3] - result[0][3]) < error);
Assert.IsTrue(Math.Abs(identity[1][0] - result[1][0]) < error);
Assert.IsTrue(Math.Abs(identity[1][1] - result[1][1]) < error);
Assert.IsTrue(Math.Abs(identity[1][2] - result[1][2]) < error);
Assert.IsTrue(Math.Abs(identity[1][3] - result[1][3]) < error);
Assert.IsTrue(Math.Abs(identity[2][0] - result[2][0]) < error);
Assert.IsTrue(Math.Abs(identity[2][1] - result[2][1]) < error);
Assert.IsTrue(Math.Abs(identity[2][2] - result[2][2]) < error);
Assert.IsTrue(Math.Abs(identity[2][3] - result[2][3]) < error);
Assert.IsTrue(Math.Abs(identity[3][0] - result[3][0]) < error);
Assert.IsTrue(Math.Abs(identity[3][1] - result[3][1]) < error);
Assert.IsTrue(Math.Abs(identity[3][2] - result[3][2]) < error);
Assert.IsTrue(Math.Abs(identity[3][3] - result[3][3]) < error);
}
public void MatrixDeterminantPerformanceTest()
{
Stopwatch watch = new Stopwatch();
double[][] bigMatrix = MatrixOperations.MatrixIdentity(10);
watch.Start();
double determinant = bigMatrix.MatrixDeterminant();
Assert.IsTrue(determinant != 0.0);
Console.Write($"Calculation took {watch.Elapsed.TotalSeconds} seconds!");
}
public void MatrixInversePerformanceTest()
{
Stopwatch watch = new Stopwatch();
double[][] bigMatrix = MatrixOperations.MatrixIdentity(2000);
watch.Start();
double[][] inverse = bigMatrix.MatrixInverse();
Assert.IsNotNull(inverse);
Assert.AreEqual(1.0, inverse[0][0]);
Assert.AreEqual(1.0, inverse[1][1]);
Assert.AreEqual(1.0, inverse[2][2]);
Console.Write($"Calculation took {watch.Elapsed.TotalSeconds} seconds!");
}
